[Federal Register: March 19, 2003 (Volume 68, Number 53)]

[Rules and Regulations]               

[Page 13497-13520]

From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[DOCID:fr19mr03-18]                         





[[Page 13497]]



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Part III











Department of the Interior











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Fish and Wildlife Service







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50 CFR Part 17







Endangered and Threatened Wildlife and Plants; Determination of 

Endangered Status for the Sonoma County Distinct Population Segment of 

the California Tiger Salamander; Final Rule





[[Page 13498]]





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DEPARTMENT OF THE INTERIOR



Fish and Wildlife Service



50 CFR Part 17



RIN 1018-AI61



 

Endangered and Threatened Wildlife and Plants; Determination of 

Endangered Status for the Sonoma County Distinct Population Segment of 

the California Tiger Salamander



AGENCY: Fish and Wildlife Service, Interior.



ACTION: Final rule.



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SUMMARY: We, the Fish and Wildlife Service (Service), determine 

endangered status for the Sonoma County distinct population segment 

(DPS) of the California tiger salamander (Ambystoma californiense), 

under the Endangered Species Act of 1973, as amended (Act). In Sonoma 

County, the California tiger salamander is imperiled by a variety of 

factors including habitat destruction, degradation, and fragmentation 

due to urban development, hybridization with non-native salamanders, 

inadequate regulatory mechanisms, disease, and pesticide drift. We 

listed this DPS on an emergency basis on July 22, 2002. The emergency 

designation expires on March 19, 2003. This rule is effective upon 

publication in the Federal Register, and implements the Federal 

protection and recovery provisions afforded by the Act for the Sonoma 

County DPS of the California tiger salamander. This final rule is being 

issued as a result of a settlement agreement and consent decree.



DATES: This rule is effective on March 19, 2003.



ADDRESSES: The complete file for this final rule is available for 

inspection, by appointment, during normal business hours at the 

Sacramento Fish and Wildlife Office, U.S. Fish and Wildlife Service, 

2800 Cottage Way, Suite W-2605, Sacramento, CA 95825.



FOR FURTHER INFORMATION CONTACT: David E. Wooten, Susan Moore, or Chris 

Nagano, Sacramento Fish and Wildlife Office, at the address listed 

above (telephone 916/414-6600; facsimile 916/414-6713).



SUPPLEMENTARY INFORMATION:



Background



    The California tiger salamander was first described as Ambystoma 

californiense by Gray in 1853, based on specimens that had been 

collected in Monterey, California (Grinnell and Camp 1917). Storer 

(1925) and Bishop (1943) also considered the California tiger 

salamander to be a distinct species. Dunn (1940), Gehlbach (1967), and 

Frost (1985) stated that the California tiger salamander was a 

subspecies of the more widespread tiger salamander (Ambystoma 

tigrinum). However, based on recent studies of the genetics, geographic 

distribution, and ecological differences among the members of the A. 

tigrinum complex, the California tiger salamander is now considered to 

be a distinct species (Shaffer and Stanley 1991; Shaffer et al. 1993; 

Jones 1993; Shaffer and McKnight 1996; Irschick and Shaffer 1997; 

Petranka 1998). The range of this animal does not naturally overlap 

with any other species of tiger salamander (Stebbins 1985; Petranka 

1998).

    The California tiger salamander is a large, stocky, terrestrial 

salamander with small eyes and a broad, rounded snout. Adults may reach 

a total length of 208 millimeters (mm) (8.2 inches (in)), with males 

generally averaging about 203 mm (8 in) in total length and females 

averaging about 173 mm (6.8 in) in total length. For both sexes, the 

average snout-vent length is approximately 91 mm (3.6 in). The small 

eyes have black irises and protrude from the head. Coloration consists 

of white or pale yellow spots or bars on a black background on the back 

and sides. The belly varies from almost uniform white or pale yellow to 

a variegated pattern of white or pale yellow and black. Males can be 

distinguished from females, especially during the breeding season, by 

their swollen cloacae (a common chamber into which the intestinal, 

urinary, and reproductive canals discharge), more developed tail fins, 

and larger overall size (Stebbins 1962; Loredo and Van Vuren 1996).

    California tiger salamanders are restricted to vernal pools and 

seasonal ponds in grassland and oak savannah plant communities from sea 

level to about 460 meters (m) (1,500 feet (ft)) (Stebbins 1989; Shaffer 

et al. 1993; Jennings and Hayes 1994; Petranka 1998; California Natural 

Diversity Data Base (CNDDB) 2002). Genetic studies of the California 

tiger salamander suggest that levels of interchange among populations 

are very low, and that populations or groups of subpopulations 

(metapopulations) are genetically isolated from one another (Shaffer et 

al. 1993; Shaffer and Trenham 2002). Studies of mitochondrial DNA and 

allozymes (proteins) indicate that there are six populations of 

Ambystoma californiense, which are found in: (1) The Santa Rosa area of 

Sonoma County; (2) the Bay Area (central and southern Alameda, Santa 

Clara, western Stanislaus, western Merced, and the majority of San 

Benito counties); (3) the Central Valley (Yolo, Sacramento, Solano, 

eastern Contra Costa, northeast Alameda, San Joaquin, Stanislaus, 

Merced, and northwestern Madera counties); (4) southern San Joaquin 

Valley (portions of Madera, central Fresno, and northern Tulare and 

Kings counties); (5) the Central Coast Range (southern Santa Cruz, 

Monterey, northern San Luis Obispo, and portions of western San Benito, 

Fresno, and Kern counties); and (6) Santa Barbara County (Shaffer and 

Trenham 2002).

    The California tiger salamander in Sonoma County inhabits low-

elevation (below 60 m (200 ft)) vernal pools and seasonal ponds, 

associated grassland, and oak savannah plant communities. The historic 

range of the species also may have included the Petaluma River 

watershed, as there is one historic record of a specimen from the 

vicinity of Petaluma from the mid-1800s (Borland 1856, as cited in 

Storer 1925).

    California tiger salamanders found in the Santa Rosa Plain in 

Sonoma County are geographically separated from other California tiger 

salamander populations. The closest California tiger salamander 

populations to Sonoma County are located in Contra Costa, Yolo, and 

Solano counties, which are separated from the Sonoma County population 

by the Coast Range, Napa River, and the Carquinez Straits, a distance 

of about 72 kilometers (km) (45 miles (mi)).

    Subadult and adult California tiger salamanders spend the dry 

summer and fall months of the year estivating (a state of dormancy or 

inactivity in response to hot, dry weather) in the burrows of small 

mammals, such as California ground squirrels (Spermophilus beecheyi) 

and Botta's pocket gopher (Thomomys bottae) (Storer 1925; Loredo and 

Van Vuren 1996; Petranka 1998; Trenham 1998a). During estivation, 

California tiger salamanders eat very little (Shaffer et al. 1993). 

Once fall or winter rains begin, they emerge from these retreats on 

rainy nights to feed and to migrate to the breeding ponds (Stebbins 

1985, 1989; Shaffer, et al. 1993). The salamanders breeding in, and 

living around, a seasonal pool or pools, and associated uplands where 

estivation can occur are said to occupy a breeding site. A breeding 

site is defined as a location where the animals are able to 

successfully breed in years of ``normal'' rainfall and complete their 

estivation (derived from Trenham 1998b and 2001). Normal rainfall in 

Santa Rosa is 76 centimeters (cm) (30 in) per year (National Weather 

Service 2002).

    Occurrence of California tiger salamanders in Sonoma County is 

significantly associated with occurrence



[[Page 13499]]



of gophers (D. Cook, The Wildlife Society, pers. comm., 2002). Active 

gopher burrows probably are needed to sustain California tiger 

salamanders because inactive burrow systems become progressively 

unsuitable over time. California tiger salamanders cannot persist 

without estivation habitat.

    Adult California tiger salamanders may migrate up to 2 km (1 mi) 

from their estivation sites to the breeding ponds (S. Sweet, University 

of California, Santa Barbara, in litt., 1998), which may be vernal 

pools, stockponds, or other seasonal water bodies. The distance between 

the estivation sites and breeding pools depends on local topography and 

vegetation, and the distribution of ground squirrel or other rodent 

burrows (Stebbins 1989; Lawrence Hunt, consultant, in litt., 1998). 

Males migrate before females (Twitty 1941; Shaffer et al. 1993; Loredo 

and Van Vuren 1996; Trenham 1998b). Males usually remain in the ponds 

for an average of about 6 to 8 weeks, while females stay for 

approximately 1 to 2 weeks. In dry years, both sexes may stay for 

shorter periods (Loredo and Van Vuren 1996; Trenham 1998b). Most marked 

salamanders have been recaptured at the pond where they were initially 

captured; in one study approximately 80 percent were recaptured at the 

same pond (Trenham 1998b). The rate of natural movement of salamanders 

among breeding sites depends on the distance between the ponds or 

complexes of ponds and on the intervening habitat (e.g., salamanders 

may move more quickly through sparsely covered and more open grassland 

than densely vegetated lands) (Trenham 1998a). As with migration 

distances, the number of ponds used by an individual over its lifetime 

will be dependent on landscape features and environmental factors.

    The adults mate in the ponds and the females lay their eggs in the 

water (Twitty 1941; Shaffer et al. 1993; Petranka 1998). Females attach 

their eggs singly, or in rare circumstances, in groups of two to four, 

to twigs, grass stems, vegetation, or debris (Storer 1925; Twitty 

1941). In ponds with no or limited vegetation, they may be attached to 

objects, such as rocks and boards on the bottom (Jennings and Hayes 

1994). After breeding, adults leave the pool and return to the small 

mammal burrows (Loredo et al. 1996; Trenham 1998a), although they may 

continue to come out nightly for approximately the next 2 weeks to feed 

(Shaffer et al. 1993). In drought years, the seasonal pools may not 

form and the adults can not breed (Barry and Shaffer 1994).

    Salamander eggs hatch in 10 to 14 days with newly hatched 

salamanders (larvae) ranging from 11.5 to 14.2 mm (0.45 to 0.55 in) in 

total length (Petranka 1998). The larvae are aquatic. They are 

yellowish gray in color and have broad fat heads, possess large, 

feathery external gills, and broad dorsal fins that extend well onto 

their back. The larvae feed on zooplankton, small crustaceans, and 

aquatic insects for about 6 weeks after hatching, after which they 

switch to larger prey (J. Anderson 1968). Larger larvae have been known 

to consume smaller tadpoles of Pacific treefrogs (Pseudacris regilla) 

and California red-legged frogs (Rana aurora) (J. Anderson 1968; P. 

Anderson 1968). The larvae are among the top aquatic predators in the 

seasonal pool ecosystems. They often rest on the bottom in shallow 

water, but also may be found at different layers in the water column in 

deeper water. The young salamanders are wary and when approached by 

potential predators will dart into vegetation on the bottom of the pool 

(Storer 1925).

    The larval stage of the California tiger salamander usually lasts 3 

to 6 months, as most seasonal ponds and pools dry up during the summer 

(Petranka 1998). Amphibian larvae must grow to a critical minimum body 

size before they can metamorphose (change into a different physical 

form) to the terrestrial stage (Wilbur and Collins 1973). Individuals 

collected near Stockton in the Central Valley during April varied from 

47 to 58 mm (1.85 to 2.3 in) in length (Storer 1925). Feaver (1971) 

found that larvae metamorphosed and left the breeding pools 60 to 94 

days after the eggs had been laid, with larvae developing faster in 

smaller, more rapidly drying pools. The longer the ponding duration, 

the larger the larvae and metamorphosed juveniles are able to grow, and 

the more likely they are to survive and reproduce (Pechmann et al. 

1989; Semlitsch et al. 1988; Morey 1998; Trenham 1998b). The larvae 

will perish if a site dries before they complete metamorphosis (P. 

Anderson 1968; Feaver 1971). Pechmann et al. (1989) found a strong 

positive correlation between ponding duration and total number of 

metamorphosing juveniles in five salamander species. In Madera County, 

Feaver (1971) found that only 11 of 30 pools sampled supported larval 

California tiger salamanders, and five of these dried before 

metamorphosis could occur. Therefore, out of the original 30 pools, 

only six (20 percent) provided suitable conditions for successful 

reproduction that year. Size at metamorphosis is positively correlated 

with stored body fat and survival of juvenile amphibians, and 

negatively correlated with age at first reproduction (Semlitsch et al. 

1988; Scott 1994; Morey 1998).

    When the metamorphosed juveniles leave their ponds in the late 

spring or early summer, before the ponds dry completely, they settle in 

small mammal burrows at the end of their nightly movements (Zeiner et 

al. 1988; Shaffer et al. 1993; Loredo et al. 1996). Like the adults, 

juveniles may emerge from these retreats to feed during nights of high 

relative humidity (Storer 1925; Shaffer et al. 1993) before settling in 

their selected estivation sites for the dry, hot summer months. 

Juveniles have been observed to migrate up to 1.6 km (1 mi) from 

breeding ponds to estivation areas (Austin and Shaffer 1992).

    An estimated 83 percent of the salamanders rely on rodent burrows 

for shelter (Petranka 1998). Mortality of juveniles during their first 

summer exceeds 50 percent (Trenham 1998b). Emergence from estivation in 

hot dry weather occasionally results in mass mortality of juveniles 

(Holland et al. 1990). Juveniles do not typically return to the 

breeding pools until they reach sexual maturity at several years of age 

(Trenham 1998b; L. Hunt, in litt., 1998). Trenham (1998b) estimated 

survival from metamorphosis to maturity at his study site at less than 

5 percent, well below the estimated replacement level of 18 percent 

that would maintain the population. Adult survivorship varies greatly 

between years, but is a crucial determinant of whether a population is 

a source or sink (i.e., whether net productivity exceeds the level 

necessary to maintain the population).

    Lifetime reproductive success for California and other tiger 

salamanders is low. Trenham et al. (2000) found the average female bred 

1.4 times and produced 8.5 young that survived to metamorphosis per 

reproductive effort. This resulted in roughly 11 metamorphic offspring 

over the lifetime of a female. Preliminary data suggest that most 

individuals of the California tiger salamanders require 2 years to 

become sexually mature, but some individuals may be slower to mature 

(Shaffer et al. 1993). Some animals do not breed until they are 4 to 6 

years old. While individuals may survive for more than 10 years, many 

breed only once, and in some populations, less than 5 percent of marked 

juveniles survive to become breeding adults (Trenham 1998b). With such 

low recruitment, isolated populations can decline greatly from unusual, 

randomly occurring natural events as well as from human caused factors 

that reduce breeding success and individual survival. Factors



[[Page 13500]]



that repeatedly lower breeding success in isolated ponds that are too 

far from other ponds for migrating individuals to replenish the 

population can quickly extirpate a population.

    The total number of individual California tiger salamanders in 

Sonoma County is not known. The difficulty of estimating total 

California tiger salamander population size has been discussed by a 

number of biologists (Shaffer et al. 1993; Jennings and Hayes 1994). 

However, estimates have been made for a few populations in Monterey 

(Barry and Shaffer 1994; Trenham et al. 1998b). Because data on numbers 

of individual California tiger salamanders are lacking since these 

amphibians spend much of their lives underground, and because only a 

portion of the total number of animals migrate to pools to breed each 

year, the availability of suitable habitat and documentation of its 

loss is thus an appropriate method for assessing the status of the 

species.

    The life history and ecology of the California tiger salamander on 

the Santa Rosa Plain in Sonoma County make it likely that this 

population has a metapopulation structure (Hanski and Gilpin 1991). A 

metapopulation is a set of local populations or breeding sites within 

an area, where typically migration from one local population or 

breeding site to other areas containing suitable habitat is possible, 

but not routine. Movement between areas containing suitable habitat 

(i.e., dispersal) is restricted due to inhospitable conditions around 

and between areas of suitable habitat. Because many of the areas of 

suitable habitat may be small, and support small numbers of 

salamanders, local extinction of these small units may be common. A 

metapopulation's persistence depends on the combined dynamics of these 

local extinctions and the subsequent recolonization of these areas by 

dispersal (Hanski and Gilpin 1991, 1997; McCullough 1996; Hanski 1999).

    We believe habitat loss has reduced the sizes and connectivity 

between patches of suitable and occupied salamander habitat on the 

Santa Rosa Plain. The reduction in the extent and amount of suitable 

water bodies, grasslands, and other suitable upland habitats likely has 

eliminated connectivity among most of the known breeding sites, making 

recolonization of some sites more difficult following local extinction. 

In addition, the reduction of habitat below a certain size threshold 

has the effect of reducing the quality of the remaining habitat by 

reducing the size of habitat boundaries, and making effects of other 

factors such as amount of food, availability of rodent burrows, 

pesticide use, mortality from vehicles, and predators more pronounced 

given the smaller area now exposed to such impacts. We do not have 

enough data to determine what the size threshold for habitat might be, 

whereby any further reduction would lower the quality of the remaining 

habitat. The acreage is probably dependent on factors such as the type 

of building occurring along habitat boundaries (i.e., residential, 

industrial, community park), number of roads bordering the habitat and 

the amount of traffic those roads experience, amount of pesticide use 

within the breeding pool watershed, or whether domestic animals or 

people have access to the site during periods when salamanders are 

vulnerable, such as migrating to or from estivation sites. We believe 

there is a size threshold for habitat below which the combination of 

various impacts will result in the loss of more salamanders than the 

Sonoma County California tiger salamander population can produce, and 

thus local extinction will occur.



Distinct Vertebrate Population Segment



    Under the Act, we must consider for listing any species, 

subspecies, or, for vertebrates, a DPS of these taxa, if there is 

sufficient information to indicate that such action may be warranted. 

To implement the measures prescribed by the Act and its Congressional 

guidance, we, along with the National Marine Fisheries Service, 

developed policy that addresses the recognition of DPSs for potential 

listing actions (61 FR 4722). The policy allows for a more refined 

application of the Act that better reflects the biological needs of the 

taxon being considered, and avoids the inclusion of entities that do 

not require its protective measures. Under our DPS policy, we use two 

elements to assess whether a population segment under consideration for 

listing may be recognized as a DPS. The elements are: (1) The 

population segment's discreteness from the remainder of the species to 

which it belongs; and (2) the significance of the population segment to 

the species to which it belongs. If we determine that a population 

segment being considered for listing represents a DPS, then the level 

of threat to that population segment is evaluated based on the five 

listing factors established by the Act to determine if listing it as 

either threatened or endangered is warranted.



Discreteness



    A population segment of a vertebrate species may be considered 

discrete if it satisfies either one of the following two conditions: 

(1) It is markedly separated from other populations of the same taxon 

as a consequence of physical, physiological, ecological, or behavioral 

factors (Quantitative measures of genetic or morphological 

discontinuity may provide evidence of this separation.); or (2) it is 

delimited by international governmental boundaries within which 

significant differences in control of exploitation, management of 

habitat, conservation status, or regulatory mechanisms exist.

    The Sonoma County California tiger salamander is discrete in 

relation to the remainder of the species. The population is 

geographically isolated and separate from other California tiger 

salamanders. The Sonoma County population is widely separated 

geographically from the closest populations, which are located in 

Contra Costa, Yolo, and Solano counties. These populations are 

separated from the Sonoma County population by the Coast Range, Napa 

River, and the Carquinez Straits, at a minimum distance of about 72 km 

(45 mi). There are no known records of the California tiger salamander 

in the intervening areas (D. Warenycia, CDFG, pers. comm., 2002). We 

have no evidence of natural interchange of individuals between the 

Sonoma County population and other California tiger salamander 

populations. As detailed below, this finding is supported by an 

evaluation of the genetic variability of the species.

    Dr. H. Bradley Shaffer has analyzed the population genetics of the 

California tiger salamander (Shaffer et al. 1993; Shaffer and Trenham 

2002). The most recently available and most comprehensive mitochondrial 

DNA (mtDNA) sequence data indicate that there are six populations of 

California tiger salamander; these six populations are distinguished 

from one another by their mtDNA characteristics (Shaffer and Trenham 

2002). Shaffer et al. 1993 reported that the sequence divergence (a 

percentage indicating the difference among DNA sequences studied) 

between the Sonoma County population was found to diverge on the order 

of 2 percent from other populations of this species. This high level of 

genetic divergence indicates that there has been little, if any, gene 

flow for a significant period of time between the Sonoma County 

population and other California tiger salamander populations. These 

results are supported by additional sampling and mtDNA work of Shaffer 

and Trenham (2002). The ``first, deepest and most significant 

phylogenetic split within California tiger salamander samples is 

between Sonoma County and all others'' (H.B. Shaffer, University of



[[Page 13501]]



California, Davis, in litt, 2002). This is illustrated by the 

phylogenetic tree based on mtDNA in which Sonoma County California 

tiger salamander is the first branch after the outgroup (groups known 

from independent evidence to have branched off earlier than the groups 

under study; Avise 1994, Weir 1996) (Shaffer and Trenham 2002). This 

branch is strongly supported statistically (with bootstrap probability 

of 100 percent) on a phylogenetic tree constructed by the neighbor 

joining method (a method used to construct phylogenetic trees; NJ, 

Avise 1994, Weir 1996). Bootstrapping is a method of statistically 

testing the significance of particular patterns; it involves resampling 

(with replacement) from the existing data sets and then reassessing the 

frequency with which particular groups appear in trees generated from 

the resampled data (Avise 1994, Weir 1996). For the Sonoma County 

California tiger salamander branch a bootstrap probability of 100 

percent means that 100 percent of the trees generated from the 

resampled data had the same configuration. A bootstrap probability of 

seventy percent is the normal criterion for statistical significance in 

the systematic literature (Hillis and Bull 1993 as cited in Shaffer and 

McKnight 1996). In addition to being strongly supported using the NJ 

method, the branch pattern indicating that the Sonoma County population 

is distinct is supported by maximum likelihood and parsimony (Shaffer 

and Trenham 2002), two other methods of constructing phylogenetic trees 

(Avise 1994, Weir 1996). In addition, Shaffer and Trenham (2002) report 

preliminary results of analyses of two nuclear genes. These preliminary 

results also show that Sonoma County California tiger salamanders are 

genetically distinct from other California tiger salamanders. Shaffer 

et al. (1993) suggest that the differences are so large that the Sonoma 

County population may warrant separate taxonomic recognition (Shaffer 

et al. 1993).

    In the proposed rule we relied on the 2 percent divergence value as 

evidence that the Sonoma County California tiger salamander population 

is discrete. At the time, we were using the best available information 

(Shaffer et al. 1993). We note that systematists typically identify 

species boundaries by using phylogenetic analysis rather than absolute 

levels of sequence divergence (Avise 1994, Weir 1996, Hedrick 2000). As 

noted above, the phylogenetic tree (which indicates relationships among 

populations or groups) constructed from the more comprehensive mtDNA 

data of Shaffer and Trenham (2002) indicates that Sonoma County 

California tiger salamanders are very distinct relative to other 

California tiger salamanders, and separated from them on a branch that 

is strongly supported statistically. Therefore, the most comprehensive 

available genetic data (Shaffer and Trenham 2002) for California tiger 

salamanders strongly indicate that Sonoma County California tiger 

salamanders are distinct from other populations of the species.



Significance



    Under our DPS policy, once we have determined that a population 

segment is discrete, we consider its biological and ecological 

significance to the larger taxon to which it belongs. This 

consideration may include, but is not limited to, evidence of the 

persistence of the discrete population segment in an ecological setting 

that is unique for the taxon; evidence that loss of the population 

segment would result in a significant gap in the range of the taxon; 

evidence that the population segment represents the only surviving 

natural occurrence of a taxon that may be more abundant elsewhere as an 

introduced population outside its historic range; and evidence that the 

discrete population segment differs markedly from other populations of 

the species in its genetic characteristics. We have found substantial 

evidence that two of these significance factors are met by the 

population of the California tiger salamander that occurs on the Santa 

Rosa Plain in Sonoma County.

    The extinction of the Sonoma County population would result in the 

loss of a significant genetic entity and the curtailment of the range 

of the species. As discussed above, the Sonoma County population is 

genetically distinct from other populations of California tiger 

salamanders. Loss of the Sonoma County population would also eliminate 

the most northern coastal extent of the range of the species. The 

Sonoma County population is geographically isolated. Genetic analysis 

of the species supports the hypothesis that no natural interchange of 

the Sonoma County population occurs with other California tiger 

salamander populations.



Conclusion



    We evaluated the Sonoma County population, addressing the two 

elements which our policy requires us to consider in deciding whether a 

vertebrate population may be recognized as a DPS and considered for 

listing under the Act. We conclude that the Sonoma County population is 

discrete, as per our policy, based on its geographic separation and 

genetic divergence from the rest of the California tiger salamander 

populations. We conclude that the Sonoma County population of the 

California tiger salamander is significant because the loss of the 

species from the Santa Rosa Plain in Sonoma County would result in a 

significant reduction in the species' range and would constitute loss 

of a genetically divergent portion of the species. Because the 

population segment meets both the discreteness and significance 

criteria of our DPS policy, the Sonoma County population of the 

California tiger salamander constitutes a DPS which qualifies for 

consideration for listing. An evaluation of the level of threat to the 

DPS based on the five listing factors established by the Act follows.



Previous Federal Action



    On September 18, 1985, we published the Vertebrate Notice of Review 

(NOR) (50 FR 37958), which included the California tiger salamander as 

a category 2 candidate species for possible future listing as 

threatened or endangered. Category 2 candidates were those taxa for 

which information contained in our files indicated that listing may be 

appropriate but for which additional data were needed to support a 

listing proposal. The January 6, 1989, and November 21, 1991, NORs (54 

FR 554 and 56 FR 58804, respectively) also included the California 

tiger salamander as a category 2 candidate, soliciting information on 

the status of the species.

    On February 21, 1992, we received a petition from Dr. H. Bradley 

Shaffer of the University of California, Davis (UCD), to list the 

California tiger salamander as an endangered species. We published a 

90-day petition finding on November 19, 1992 (57 FR 54545), concluding 

that the petition presented substantial information indicating that 

listing may be warranted. On April 18, 1994, we published a 12-month 

petition finding (59 FR 18353) that the listing of the California tiger 

salamander was warranted but precluded by higher priority listing 

actions. We elevated the species to category 1 status at that time, 

which was reflected in the November 15, 1994, NOR (59 FR 58982). 

Category 1 candidates were those taxa for which we had on file 

sufficient information on biological vulnerability and threats to 

support preparation of listing proposals.

    We discontinued the use of different categories of candidates in 

the February 28, 1996, NOR (61 FR 7596), and defined ``candidate 

species'' as those meeting the definition of former category 1. We 

maintained the California tiger salamander as a candidate species in 

that NOR, as well



[[Page 13502]]



as subsequent NORs published September 19, 1997 (62 FR 49398), October 

25, 1999 (64 FR 57533), and October 30, 2001 (66 FR 54808).

    On June 12, 2001, we received a petition dated June 11, 2001, from 

the Center for Biological Diversity (CBD) and Citizens for a 

Sustainable Cotati to emergency list the Sonoma County population of 

the California tiger salamander as an endangered species and to 

designate critical habitat. On February 27, 2002, CBD filed a complaint 

for our failure to emergency list the Sonoma County population of the 

California tiger salamander as endangered (Center for Biological 

Diversity v. U.S. Fish and Wildlife Service (N.D.Cal.) (Case No. C-02-

0558 WHA)). On June 6, 2002, based on a settlement agreement with the 

CBD, the court signed an order requiring us to submit for publication 

in the Federal Register, a proposed and/or emergency rule to list the 

species by July 15, 2002.

    On July 22, 2002, we published in the Federal Register an emergency 

rule listing the Sonoma County distinct population segment (DPS) of the 

California tiger salamander (Sonoma County California tiger salamander) 

on an emergency basis because we found that a number of threats 

constituted immediate and significant risk to the species (67 FR 

47726). We concurrently published a proposed rule to list this taxon as 

endangered (67 FR 47758). The proposed rule opened a 60-day comment 

period which closed on September 20, 2002. On August 26, 2002, we 

published a notice in the Federal Register notifying the public of a 

hearing to be held on October 1, 2002, and extending the comment period 

until October 21, 2002 (67 FR 54761). On October 31, 2002, we re-opened 

the comment period for 45 days (67 FR 66377). The re-opened public 

comment period closed on December 16, 2002. This final rule to 

designate the Sonoma County California tiger salamander as an 

endangered species complies with the June 6, 2002, settlement 

agreement.

    As required by section 4(b)(1) of the Act, our decision to list the 

Sonoma County population of the California tiger salamander is based 

upon the best available information at this time. We note that the 

petition and subsequent emergency listing of this population has led to 

increased interest in this population by a variety of parties, and thus 

to an acceleration of the rate at which new information is becoming 

available. We expect this trend to continue subsequent to this final 

listing determination. The settlement agreement discussed above 

requires that we submit to the Federal Register a proposed rule to list 

the California tiger salamander range wide by May 15, 2003, and make a 

final listing determination on that proposal by May 15, 2004. As a part 

of that rulemaking we intend to review all then-current information 

regarding both the Sonoma County and Santa Barbara County populations, 

including whether they constitute valid distinct population segments, 

and render a final determination on the California tiger salamander 

accordingly.



Summary of Comments and Recommendations



    In the July 22, 2002, proposed rule (67 FR 47758), we requested all 

interested parties submit factual reports, information, and comments 

that might contribute to development of a final determination. We 

contacted appropriate Federal agencies, State agencies, county and city 

governments, scientific organizations, affected landowners and other 

interested parties requesting comments. We published legal notices in 

the Santa Rosa Press Democrat on July 29, 2002, and September 3, 2002, 

and the Sonoma Index-Tribune on July 30, 2002, and September 27, 2002, 

notifying the public of the comment period on the proposed and 

emergency rule and the public hearing, respectively. We requested 12 

peer reviewers to comment on the proposed rule in compliance with our 

policy, published in the Federal Register on July 1, 1994 (59 FR 

34270).

    During both public comment periods, we received 111 comment letters 

from public agencies, individuals, businesses, and organizations, with 

several commenters submitting more than one set of comments during the 

subsequent extensions of the comment period. We received oral comments 

from 49 people at the public hearing. Ninety-nine commenters opposed 

the listing, 60 supported the listing, and one was neutral. The 

breakdown of the comments included none from Federal agencies, 2 from 

State agencies, 8 from Sonoma County and city agencies, 49 from 

organizations or corporations, and 99 from individuals. One hundred and 

twenty people attended the hearing, with 31 individuals and 18 

representatives of organizations providing oral comments. In total, 39 

commenters at the hearing were opposed to the listing, 9 supported the 

listing, and 1 was neutral. Several comments were received after the 

comment period closed.

    We updated the final rule to reflect comments and information we 

received during the comment periods. We address substantive comments 

concerning the rule below. Comments of a similar nature are grouped 

together (referred to as ``Issues'' for the purpose of this summary).

    Issue 1: Some commenters questioned the validity of our DPS 

determination for Sonoma County California tiger salamander, suggesting 

that the genetic data do not support a DPS. One commenter specifically 

suggested that the evidence that Sonoma County California tiger 

salamander is a separate species or subspecies and use of this as a 

criterion for a DPS is less clear than we indicated in our emergency 

rule. The commenter also suggests that there is little evidence that 

California tiger salamander populations in different parts of 

California represent separate species or subspecies. The commenter also 

noted that, while the unpublished Shaffer et al. (1993) suggest Sonoma 

County may warrant species status, Shaffer and McKnight (1996) make no 

such claim in their published paper.

    Response: Genetic distinctness or the presence of genetically 

determined traits may be important in recognizing some DPS's, but this 

kind of evidence is not specifically required in order for a DPS to be 

recognized. Genetic information can play two different roles in the 

evaluation of whether a population should be recognized as a distinct 

vertebrate population segment for the purposes of listing under the 

Act. First, quantitative genetic information may, but is not required 

in order to provide evidence that the population is markedly separated 

from other populations and thus meets the DPS policy's criterion of 

being discrete. The DPS policy's standard for discreteness is meant to 

allow an entity given DPS status under the Act to be adequately defined 

and described. The standard adopted is believed to allow entities 

recognized under the Act to be identified without requiring an 

unreasonably rigid test for distinctness. At the same time, the 

standard does not require absolute separation of a DPS from other 

members of its species, because this can rarely be demonstrated in 

nature for any population of organisms. Second, genetic characteristics 

that differ markedly from other populations may be one consideration in 

evaluating the discrete population segments biological and ecological 

significance to the taxon to which it belongs.

    Restricting listings to full taxonomic species would render the 

Act's definition of species, which explicitly includes subspecies and 

DPS's of vertebrates, superfluous.



[[Page 13503]]



    We did note in our emergency rule that Dr. Shaffer and his 

colleagues believe the divergence of Sonoma County California tiger 

salamanders justifies separate species recognition (Shaffer et al. 

1993). Our DPS policy (61 FR 4722), however, does not require that 

levels of differentiation warranting taxonomic revision be identified 

for the DPS criteria to be met. In fact, our DPS policy is used for 

identifying groups within species or subspecies that may warrant 

listing under the ESA. Therefore, our DPS determination for Sonoma 

County California tiger salamander is not based on whether the 

divergence observed warrants separate taxonomic recognition, but rather 

on the relatively high divergence of the Sonoma County population from 

other populations of California tiger salamanders.

    The Sonoma County population of California tiger salamanders is the 

most divergent of any population of the species. This finding is 

supported by the original mitochondrial DNA (mtDNA) work of Shaffer et 

al. (1993) and by additional sampling and mtDNA work of Shaffer and 

Trenham (2002). The ``first, deepest and most significant phylogenetic 

split within California tiger salamander samples is between Sonoma 

County and all others'' (H.B. Shaffer, in litt., 2002). This is 

illustrated by the phylogenetic tree based on mtDNA in which Sonoma 

County California tiger salamander is the first branch after the 

outgroup (Shaffer and Trenham 2002). This branch is strongly supported 

statistically (with bootstrap probability of 100 percent) on a 

phylogenetic tree constructed by the neighbor joining (NJ) method. 

Seventy percent is the normal criterion for statistical significance of 

bootstrap proportions in the systematic literature (Hillis and Bull 

1993 as cited in Shaffer and McKnight 1996). In addition, the branch 

pattern indicating that the Sonoma County population is distinct is 

supported by maximum likelihood and parsimony (Shaffer and Trenham 

2002), two other methods of constructing phylogenetic trees (Avise 

1994, Weir 1996). In addition, Shaffer and Trenham (2002) report 

preliminary results of analyses of two nuclear genes. These preliminary 

results also show that Sonoma County California tiger salamanders are 

genetically distinct from other California tiger salamanders. 

Therefore, we believe that the levels of divergence observed in Sonoma 

County California tiger salamanders provide substantial evidence of the 

significance of the population.

    Shaffer and McKnight (1996) do not mention whether the divergence 

of Sonoma County California tiger salamanders justifies separate 

species recognition. They make no statements about the taxonomic status 

of Sonoma County California tiger salamanders in their paper. In the 

Discreteness section of the emergency rule, we incorrectly attributed 

the statement that Sonoma County California tiger salamanders warrant 

separate taxonomic recognition to the 1996 publication. In fact, no 

Sonoma County California tiger salamanders were sampled in the study 

(Appendix 1 of Shaffer and McKnight 1996). The paper examined 

evolutionary relationships among tiger salamander species and 

subspecies and did not include a formal taxonomic treatment of the 

tiger salamander complex. Therefore, it is not surprising that the 

authors did not specifically note whether or not the divergence of 

Sonoma County California tiger salamanders justifies species status.

    Issue 2: One commenter also implied that the discreteness criterion 

of our DPS policy was only met by genetic data.

    Response: Two professional biologists who commented reported that 

the Sonoma County population is geographically isolated from other 

populations of the California tiger salamander. We note that the 

proposed rule discussed the geographic separation of the Sonoma County 

population from other populations of California tiger salamander. The 

Sonoma County population is separated from other California tiger 

salamander populations by the Coast Range, Napa River, and the 

Carquinez Straits, a distance of about 72 km (45 mi).

    Issue 3: Some commenters felt that 2 percent divergence of the 

Sonoma population of the California tiger salamander from the remainder 

of the California tiger salamander population is not meaningful or 

worthy of recognition as a DPS.

    Response: We note that species boundaries are typically identified 

by systematists using phylogenetic analysis rather than absolute levels 

of sequence divergence. The intraspecific sequence divergence value of 

2 percent depends on the total number of nucleotides sequenced for each 

gene region. This can differ significantly from species to species or 

from study to study and is therefore a relative value (Avise 1994, Weir 

1996, Hedrick 2000). Comparisons need to be made from the same 

baseline. From a DPS perspective, percent sequence divergence is less 

important than the phylogenetic relationships depicted with strong 

statistical support in the neighbor joining (NJ) tree that indicate the 

distinctive genetic character of Sonoma County California tiger 

salamanders. The phylogenetic tree (which indicates relationships among 

populations or groups) constructed from the mtDNA data of Shaffer and 

Trenham (2002) indicates that Sonoma County California tiger 

salamanders are very distinct relative to other California tiger 

salamanders, and separated from them on a branch that is strongly 

supported statistically. Therefore, the most comprehensive available 

genetic data (Shaffer and Trenham 2002) for California tiger 

salamanders strongly indicate that Sonoma County California tiger 

salamanders are distinct from other populations of the species.

    Issue 4: One commenter analyzed Shaffer and McKnight's (1996) 

divergence values for various Ambystoma tigrinum subspecies and for 

California tiger salamander, finding that divergence between 

populations in different groups (e.g., between California tiger 

salamander and A. tigrinum subspecies and other such combinations among 

species and subspecies versus within a species or subspecies) had a 

mean of 6.37 percent and a range of 5.08 percent to 7.41 percent. The 

commenter states that these statistics show the 2 percent divergence of 

the Sonoma County California tiger salamander population is 

unremarkable.

    Response: As noted above, one way to meet the significance 

criterion of our DPS policy (61 FR 4722) is for a population to 

``differ markedly from other populations of the species in its genetic 

characteristics'' (emphasis added). We note again that our DPS policy 

focuses on differentiation within species (i.e., the population 

``differs markedly from other populations of the species''). The 

commenter's analysis is of differences among taxonomic groups of tiger 

salamanders, not of within-species or subspecies differences, which are 

the focus of the DPS policy.

    As explained above, we believe the available mtDNA data (Shaffer et 

al. 1993, Shaffer and Trenham 2002) show that the Sonoma County 

population of California tiger salamander is markedly genetically 

divergent from other populations of the California tiger salamander. 

That the sequence divergence value is 2 percent is less important than 

the configuration of the phylogenetic tree, which strongly supports the 

distinctness of Sonoma County California tiger salamanders.

    Issue 5: One commenter stated that one would expect broadly similar 

conclusions from allozyme and mtDNA studies and that for Sonoma County 

California tiger salamanders this was not the case. The commenter noted 

that



[[Page 13504]]



Shaffer et al.'s (1993) allozyme work did not reveal much variation 

(only 9 of 26 loci were variable) and indicate that Sonoma County 

California tiger salamanders are not distinct from other western 

populations of California tiger salamander from Yolo County to San Luis 

Obispo County.

    Response: A variety of genetic tools are available to assess 

genetic variation. These tools are often referred to as ``genetic 

markers.'' All are indicators of genetic variation, but none is 

considered determinative. Which genetic marker is most useful depends 

on the question being asked and the organism being studied (Haig 1998, 

Parker et al. 1998).

    Allozymes are proteins which are used as genetic markers because 

DNA contains information that is used by cells to build protein. 

Allozymes have been used to assess genetic variation for many years. 

Allozyme studies have the advantage of being relatively inexpensive and 

straightforward, once the basic technique is developed for a group. 

However, drawbacks of using allozymes include the limited number of 

proteins that can be screened (Parker et al. 1998) and the fact that 

they often detect little variability (Haig 1998). On average across 

taxa, less than half of all loci are variable. It is not uncommon for 

population biologists to encounter species for which allozymes cannot 

be used as genetic markers because they lack variation (Parker et al. 

1998).

    Molecular techniques, such as mtDNA, allow biologists to examine 

variation in DNA directly, rather than looking at the product derived 

from DNA (i.e., proteins) (Parker et al. 1998). Analysis of animal 

mtDNA is the most commonly used technique for examining phylogenetic 

relationships among populations of the same species and among closely 

related species (Taberlet 1996). One advantage of mtDNA in particular 

is its high rate of evolution (i.e., rate of nucleotide substitution) 

compared to other DNA (Taberlet 1996, Parker et al. 1998). The D-loop 

(which Shaffer and colleagues examined for their tiger salamander 

studies) is especially variable, making it useful to study recently 

divergent populations or species. Different genetic techniques are 

expected to resolve different amounts of variation because the genetic 

markers used have different evolutionary characteristics (Parker et al. 

1998). The observation that some characters (in this case, allozymes) 

are not variable does not diminish the utility of other data (in this 

case mtDNA) in describing relationships among groups.

    Issue 6: Several commenters felt that our finding that California 

tiger salamanders in Sonoma County qualified as a DPS was based on an 

isolated, and dated, report (i.e., Shaffer et al. (1993). One commenter 

noted several times that Shaffer et al. (1993), the source of mtDNA 

data for California tiger salamanders, is an unpublished report.

    Response: We are required to use the best available scientific 

data. In this case, the data were in an unpublished report. During the 

comment period, we received a second report (Shaffer and Trenham 2002) 

that contained findings similar to Shaffer et al. 1993 but which was 

based on more extensive data collection. The publication of Shaffer and 

McKnight (1996) using mtDNA techniques for California and other tiger 

salamanders and the publication of mtDNA work by Shaffer et al. (2000) 

on Yosemite toad (Bufo canorus) gives us confidence that Shaffer's work 

is scientifically defensible.

    Issue 7: Several commenters noted that recent aerial photos and a 

map that is based on the photos show 515 or more pools located within, 

or in the vicinity of, the Santa Rosa Plain. They believe these could 

potentially provide habitat for the Sonoma County California tiger 

salamander. They stated that many of the pools have not been surveyed 

and, therefore, the species could be more widespread in Sonoma County 

than is currently known.

    Our Response: The map submitted displayed 515 water bodies and was 

based on interpretation of aerial photography with little on-the-ground 

verification. We compared the map of potential habitat for the 

California tiger salamander to information and data we obtained and 

have determined 360 water bodies can be eliminated as potential habitat 

for the California tiger salamander due to a variety of factors 

including: unsuitable soils, unsuitable vegetation, high elevation, 

presence of aquatic predators, agricultural development (row crops, 

vineyards, etc.), urbanization, and unsuitable hydrology. One hundred 

and fifty-five water bodies remained within the suitable habitat area.

    Of the 155 remaining water bodies, 53 were characterized as ``man-

made long'' and ``natural long'' ponds/wetlands, which hold water for 

too long and /or harbor aquatic predators, and were eliminated as 

potential habitat for the California tiger salamander. Another set of 

water bodies were ``man-made short'' and ``natural short'' ponds/

wetland (12 in total) which do not hold water long enough to be a 

source of potential habitat for the California tiger salamander. 

Consequently only ``man-made moderate'' and ``natural moderate'' mapped 

water bodies were considered potential suitable habitat (90 in total).

    Of the ``man-made moderate'' and ``natural moderate'' mapped water 

bodies, four were formerly known breeding sites that have been 

eliminated and eight are currently identified as existing breeding 

sites. Some of the mapped water bodies are anticipated to have aquatic 

predators given their location on the Laguna de Santa Rosa floodplain, 

which would limit California tiger salamander utilization. Others 

contain habitat with sightings near the ponds, but these ponds have 

been repeatedly surveyed by experts, with results indicating they do 

not support breeding populations of California tiger salamanders.

    The determination that some of the mapped water bodies contain 

potential habitat is solely based on aerial photographs; however, the 

majority of these are on private property and inaccessible to surveying 

without landowner permission. Several recognized salamander biologists 

have conducted repeated road surveys in Sonoma County along areas where 

the California tiger salamander is known to exist or where suitable 

habitat appears to exist (D. Cook, The Wildlife Society, pers. comm., 

2002; P. Northen, California State University, Sonoma, pers. comm., 

2002; J. Seifers, Santa Rosa, California, per. comm., 2002; H. B. 

Shaffer, pers. comm., 2002; P. C. Trenham, UCD, pers. comm., 2002). 

Night driving is a standard technique for surveying for reptiles and 

amphibians (Shaffer and Juterbock 1994; Parris 1999). The locations 

where these biologists found breeding sites, migrating adult 

salamanders, subadults, larvae, and egg masses in roadside ditches were 

entered into the CNDDB. This data is considered essential (D. McGriff, 

CDFG, pers. comm., 2002) and the data was utilized in our analysis of 

the status of the California tiger salamander in Sonoma County. Several 

of the experts indicated that there are likely to be a few small 

breeding sites or potential habitat for California tiger salamanders on 

private lands containing grassland areas and suitable soils on the 

Santa Rosa Plain, including stock ponds (P. Northen, pers. comm., 2002; 

H. B. Shaffer, pers. comm., 2002; P. C. Trenham, pers. comm., 2002); 

however, these private lands were inaccessible during their survey 

efforts.

    Issue 8: One commenter believed that two sites not specifically 

mentioned in the proposed rule should be included as breeding sites for 

California tiger salamanders.



[[Page 13505]]



    Our Response: We evaluated the two sites mentioned by the 

commenter. They are the Hartunian (Scenic Avenue) Preserve and the 

Southwestern Santa Rosa Vernal Pool Preservation Bank (Engel Bank).

    The Hartunian Preserve is approximately 14 hectares (ha) (34 acres 

(ac)) in size and has one shallow swale that could support successful 

breeding during a rainy season of above-average rainfall. This preserve 

was not listed in the emergency rule and has not been included in the 

final rule because breeding by the species is not likely to occur 

during years of low to average rainfall.

    Upon review of all information available, we have concluded that 

the Engel Bank does meet the biological requirements for California 

tiger salamander breeding and we have included this site as an eighth 

breeding site. Engel Bank is a 16-ha (40-ac) preserve that contains 

approximately 7-ha (18-ac) of wetlands and has documented records of 

the species. However, California tiger salamanders require a fairly 

large upland component. Approximately 9 ha (22 ac) of protected uplands 

are available at this site. Therefore, due to the limited upland 

habitat protected within the Engel Bank, a sustainable population at 

this site is dependent on the activities occurring on the surrounding 

private property.

    Issue 9: Many commenters stated that the California tiger 

salamander is adequately protected by current regulations. Examples of 

current regulations cited include the application of the Porter-Cologne 

Water Quality Control Act and the California Environmental Quality Act 

(CEQA) by CDFG. Both of these require one-to-one mitigation for 

projects impacting the species. Commenters also mentioned strict local 

land use controls enacted by Sonoma County and cities within the Santa 

Rosa Plain. In addition, commenters noted that the Sonoma County 

Agricultural and Open Space District has acquired potential California 

tiger salamander habitat that is set aside as open space through a 

county-wide sales tax. They felt these preserves are adequate for the 

animal. Several other commenters stated that current legal protections 

have been inadequate for the species, and losses of breeding sites have 

occurred.

    Our Response: CDFG lists the California tiger salamander as a 

species of special concern and has no specific regulatory mechanism to 

require mitigation for impacts to this species. In some instances, the 

CDFG has obtained one-to-one mitigation for destruction of California 

tiger salamander breeding sites. However, five breeding sites have been 

eliminated in Sonoma County during the past 2 years without new 

breeding sites being created. The use of CEQA and the Porter-Cologne 

Water Quality Control Act have not halted the loss of habitat for this 

species in Sonoma County. The land use controls enacted by the County 

and cities have not required adequate compensation for the loss of 

breeding sites. The Sonoma County Agricultural and Open Space District 

has acquired acreage through a one-quarter of a cent county sales tax. 

However, the acreage purchased does not overlap with areas known to 

contain California tiger salamander breeding sites. A majority of their 

purchased lands lie outside of the Santa Rosa Plain. Of the lands they 

have purchased within the Santa Rosa Plain, the majority fall within 

the floodplain of the Laguna de Santa Rosa River. There are no known 

records of the California tiger salamander within this 100 year 

floodplain.

    Issue 10: Many commenters stated that the comment period did not 

allow sufficient time for meaningful public input. A number of them 

said that more time was needed to complete surveys that currently are 

underway.

    Our Response: The comment period for the proposed rule was 

initially open for 60 days, closing on September 20, 2002. On August 

26, 2002, the comment period was extended until October 21, 2002. The 

comment period was re-opened on October 31, 2002, for an additional 45 

days. In total, the comment period was open for 145 days.

    At least 12 surveys are ongoing in Sonoma County in three areas not 

previously known to have California tiger salamander occurrences, and 

to date, there have been no detections of the animal. We agree that 

additional survey information is valuable. However, the Service has not 

had the flexibility to wait until surveys are finished because an 

order, issued by the district court in Center for Biological Diversity 

v. U.S. Fish and Wildlife Service, required us to complete this rule 

before the expiration of the protection afforded the DPS by the 

emergency rule.

    Issue 11: One commenter stated that we should extend the comment 

period because we had not made available to the public documents on 

which the emergency listing and permanent listing was based.

    Our Response: As stated in the emergency rule, the complete file 

for the rule is available for inspection, by appointment, during normal 

business hours at the Sacramento Fish and Wildlife Office. In addition, 

the proposed rule stated that all comments received during the comment 

period were available for public review. The complete file for this 

rule is available for inspection, by appointment, during normal 

business hours at the Sacramento Fish and Wildlife Office.

    Issue 12: Several commenters felt we should complete peer review 

and incorporate that analysis into a proposed rule.

    Our Response: In accordance with our July 1, 1994, Interagency 

Cooperative Policy for Peer Review in Endangered Species Act Activities 

(59 FR 34270), we solicited review from 12 experts in the fields of 

ecology, conservation, genetics, taxonomy and management. The purpose 

of such a review is to ensure that listing decisions are based on 

scientifically sound data, assumptions, and analyses, including input 

from appropriate experts. The five peer reviewers who sent comments 

supported listing of the Sonoma County California tiger salamander. 

They provided additional documentation on the distribution, genetics, 

and threats to the species. This information has been incorporated into 

this final rule.

    Issue 13: Numerous commenters felt the proposal to list the Sonoma 

County California tiger salamander was based on one study conducted by 

a group with a very specific agenda against property rights and 

development. They said listing decisions should be based on specific 

studies by non-partisan professionals. Two commenters felt that the 

proposed rule was based on inaccurate or incomplete data. Numerous 

commenters felt the data we utilized on the California tiger salamander 

was at least 10 years old and was thus not current or accurate. One 

recognized herpetologist provided additional peer-reviewed articles on 

the California tiger salamander from scientific journals. Another 

professional biologist noted the proposed rule was based on research 

conducted as recently as 2001 by knowledgeable herpetologists.

    Our Response: We used the best scientific and commercial 

information available during the status review process and preparation 

of the emergency and final rules to make our listing determination. We 

utilized museum records; CNDDB information; aerial photographs 

documenting the land use changes over the last 60 years; reports 

produced by the Sonoma County Agricultural Commissioners and the Sonoma 

County Planning and Development Department; unpublished reports by 

biologists; and peer-reviewed articles from scientific journals in 

making that determination.



[[Page 13506]]



    Out of 126 citations appearing in the emergency rule, 52 have been 

published within the past 5 years (41 percent) and 83 citations have 

been published within the past 10 years (66 percent). The initial 

report on the population genetics of the California tiger salamander by 

Shaffer et al. (1993) has been substantiated by additional research 

(Barry and Shaffer 1994; Fisher and Shaffer 1996; Shaffer and McKnight 

1996; Cook and Northen 2001; Shaffer and Trenham 2002).

    Issue 14: Some commenters felt we had not quantified the magnitude 

of loss of the California tiger salamander in Sonoma County. One 

herpetologist said we had presented accurate information on the status 

of the species in Sonoma County.

    Our Response: Based on the best available scientific and commercial 

information, five breeding sites for the California tiger salamander in 

Sonoma County have been destroyed in the past 2 years, and there are 

only eight known breeding sites remaining. Five of these sites are on 

private lands with no effective regulatory protection. Only one of the 

three protected sites is over 32 ha (80 ac) in size. All known breeding 

sites in the Cotati area have now been destroyed. The remaining sites 

in the Cotati area where the animals can mate and develop are roadside 

ditches and other suboptimal habitat during years of above average 

rainfall.

    Issue 15: According to some commenters, there has been no study to 

determine population trends or ways to improve breeding at the known 

preserves containing the California tiger salamander.

    Our Response: All of the three protected sites known to contain 

salamanders have been surveyed for the past 4 years. All surveys at 

these sites have resulted in the detection of very low numbers of 

salamander larvae during years that they were found at all. The largest 

preserve is approximately 81 ha (200 ac) in size, yet continues to 

exhibit very low numbers of larvae as indicated by yearly surveys. It 

is probable that salamander populations are limited by the lack of 

uplands for estivation during the dry season.

    Issue 16: A number of commenters asked us to delay a final listing 

decision until a full review of the scientific evidence supporting or 

disputing the status of the Sonoma County California tiger salamander 

had been presented in a public forum.

    Our Response: The purpose of publishing a proposed rule and 

soliciting public input during the comment period is to fully involve 

the public in the listing process. We also held a workshop and public 

hearing in Santa Rosa, California, to encourage agency and public input 

into the review of the proposed rule. We solicited 12 recognized 

experts and specialists to review the proposed rule. We utilized this 

information in making the final determination.

    Issue 17: Numerous commenters said the listing of the California 

tiger salamander would have a severe economic impact on Sonoma County. 

They said we should complete an analysis of the economic effects of 

listing and include it in the final rule.

    Our Response: Under section 4(b)(1)(A) of the Endangered Species 

Act of 1973, as amended (Act) (16 U.S.C. 1531 et seq.), we must base a 

listing decision solely on the best scientific and commercial data 

available. The legislative history of this provision clearly states the 

intent of Congress to ensure that listing decisions are ``* * * based 

solely on biological criteria and to prevent non-biological criteria 

from affecting such decisions* * * '' (House of Representatives Report 

Number 97-835, 97th Congress, Second Session 19 (1982)). As further 

stated in the legislative history, ``* * * economic considerations have 

no relevance to determinations regarding the status of species * * 

*''(Id. at 20). Therefore, we did not consider the economic impacts of 

listing the Sonoma County California tiger salamander.

    Issue 18: Two commenters stated that critical habitat has not been 

proposed and, therefore, the listing is in violation of the Act.

    Our Response: Pursuant to section 4(a)(3) of the Act, we have 

determined that designation of critical habitat is prudent for the 

Sonoma County California tiger salamander (see the ``Critical Habitat'' 

section). However, our budget for listing activities is currently 

insufficient to allow us to immediately complete all the listing 

actions required by the Act. Listing the DPS without designating 

critical habitat at this time allows us to provide protections needed 

for the conservation of the species without further delay. This is 

consistent with section 4(b)(6)(C)(i) of the Act, which states that 

final listing decisions may be issued without critical habitat 

designations when it is essential that such determinations be promptly 

published. We will prepare a critical habitat designation in the future 

when our available resources allow.

    Issue 19: One commenter said the 1995 Santa Rosa Plain Vernal Pool 

Ecosystem Preservation Plan indicated the Sonoma County California 

tiger salamander is potentially less vulnerable than stated in our 

proposed rule.

    Our Response: The Santa Rosa Plain has experienced rapid urban 

growth since the vernal pool ecosystem preservation plan was issued in 

1995. From 1995 until 2001, the population of Sonoma County increased 

by approximately 10% with an average annual growth rate of 

approximately 1.6 percent. (U.S. Census Bureau; California Department 

of Finance; California Association of Realtors website 2002). Increases 

in housing, traffic, industry, and office buildings have occurred 

concurrent with the increase in population growth. In the past 2 years, 

five breeding sites for the Sonoma County California tiger salamander 

have been destroyed. Loss of real and potential salamander breeding 

sites and estivation habitat continues to occur in the Santa Rosa 

Plain. Given the amount of habitat loss, inadequate regulatory 

mechanisms, and other threats, we believe the remaining California 

tiger salamanders in Sonoma County are endangered.

    Issue 20: Several commenters stated that we should compensate 

private landowners for the loss of revenue that occurs when California 

tiger salamanders are found on their land. Another commenter said the 

``Cattle Growers'' ruling prohibits us from imposing land use 

restrictions predicated upon listing except through a designation of 

critical habitat, and not doing so constitutes unlawful taking of 

property without compensation.

    Our Response: The presence of an endangered or threatened species 

does not prevent all uses of public or private lands. The listing of a 

species does not impose land use restrictions and, therefore, does not 

result in unlawful taking of property. In addition, we will assist 

landowners in the identification of proposed activities that could 

result in take (harass, harm, pursue, hunt, shoot, wound, kill, trap, 

capture, or collect, or to attempt to engage in any such conduct), 

develop measures to minimize the potential for take, and work with them 

to obtain authorizations for incidental take through sections 7 and 10 

of the Act. Recovery planning for this species may include 

recommendations for land acquisition or easements involving private 

landowners. Any such efforts will be undertaken with the full 

cooperation of the landowners.

    A recent case pertinent to this issue, Arizona Cattle Growers v. 

Fish and Wildlife and Bureau of Land Management (9th Circuit Court of 

Appeals 99-16102), provides that, in



[[Page 13507]]



biological opinions issued pursuant to section 7 of the Act, the terms 

and conditions in a biological opinion must have an articulated, 

rational connection to the take of a listed species. The court stated 

that the Act provides for the designation of critical habitat outside 

the geographic range currently occupied by a listed species when ``such 

areas are essential for the conservation of the species.'' Absent this 

procedure, the court stated that there is no evidence that Congress 

intended to allow the Service to regulate any parcel of land that is 

merely capable of supporting a listed species. Therefore, the mere 

listing of species, such as the Sonoma County California tiger 

salamander, will not result in land use restrictions.

    Issue 21: One commenter was concerned that existing vineyards and 

wineries would be burdened by excessive costs when water permits are 

required or changed, or when planting or replanting permits are 

requested.

    Our Response: Once a species becomes listed, section 9 of the Act 

sets forth a series of general prohibitions that apply to that species. 

The Sonoma County California tiger salamander is protected from 

``take'' by any person subject to the jurisdiction of the United 

States. The definition of take under the Act includes harass, harm, 

pursue, hunt, shoot, wound, kill, trap, capture, collect, or attempt to 

engage in any such conduct. Harm is further defined to include 

significant habitat modification or degradation that results in death 

or injury to the listed wildlife by significantly impairing behavioral 

patterns such as breeding, feeding, or sheltering. Harass is further 

defined to include actions that create the likelihood of injury to 

listed wildlife by annoying it to such an extent as to significantly 

disrupt normal behavior patterns which include, but are not limited to, 

breeding, feeding, or sheltering. Therefore, if the action by a party, 

such as water use by a vineyard or winery, planting or replanting of 

vineyards, could result in ``take'' of a listed species, then 

authorization for incidental take should be obtained pursuant to either 

sections 7 or 10 of the Act.

    Issue 22: One commenter felt that the CDFG considered the emergency 

listing inappropriate due to a lack of proper information and 

sufficient scientific support.

    Our Response: Only species or subspecies, and not distinct 

population segments, of vertebrates can be listed as endangered or 

threatened under the California Endangered Species Act (California 

Department of Fish and Game internet web site 2003). However, the 

California Department of Fish and Game has expressed concern for 

adverse impacts to the salamander and its habitat (R. Floerke, CDFG, in 

litt., 2002).

    Issue 23: One commenter stated that the breeding sites identified 

in the emergency rule for the Sonoma County California tiger salamander 

are not threatened, and the sites around the old airfield would not be 

destroyed because construction will avoid them and be limited to the 

runway. The commenter also felt the degree of threat, isolation of 

habitats, and barriers to movement were overstated and not based in 

reality. This same commenter believed that the Roseland Creek channel 

and asphalt run-way already constitute a significant barrier to 

migrating salamanders at the old airfield. Several other commenters 

noted the vernal pools at the Southwest Air Center (Air Center) have 

been damaged, destroyed, or are currently on the verge of being lost.

    Our Response: Other than approximately 28 ha (70 ac) designated as 

open space, the remainder of the Air Center has been designated for 

development in the Southwest Santa Rosa Area Development Plan. One of 

the breeding sites could be destroyed by development and two others 

could be isolated and imperiled by a loss of estivation habitat. Upon 

development of this area, not enough upland will likely remain to 

support a viable salamander population even if two of the three 

breeding sites are not destroyed. Proposed development could also 

isolate the Federal Emergency Management Agency (FEMA)/Broadmore North 

Preserves.

    Burrowing mammals also could be increasingly subject to control 

actions given the proximity of developed areas to any remaining 

estivation habitats. One proposed development project at the Air Center 

could fill two wetlands that make up one of the eight known breeding 

sites. Surveys of this site over the past 2 years have found breeding 

California tiger salamanders. Construction on the runway itself and 

extension of Fresno Avenue could result in total isolation of the FEMA/

Broadmore North Preserves, a known Sonoma County California tiger 

salamander breeding site. We have determined that Roseland Creek 

Channel is not likely to be a barrier to salamander migration. Flows in 

the channel are minimal, except during the heaviest of rain events.

    Issue 24: One commenter felt that the emergency rule overstated the 

effects of development at the Air Center because the runways are too 

hot for salamanders to cross.

    Our Response: Hot runways are not a concern for this species 

because California tiger salamanders are in estivation during the dry, 

hot, summer months. The nocturnal adult animals concentrate their 

movements during rain events in the cooler fall, winter, and spring 

months. Researchers conducting night-time road surveys for California 

tiger salamanders during the fall, winter, and spring have documented 

this species crossing roads on many occasions.

    Issue 25: One commenter stated that California tiger salamanders 

exist in the Central Valley and coastal areas of California and, 

therefore, they could not be endangered.

    Our Response: Research has indicated there are six populations of 

California tiger salamanders occurring in California. These include the 

Santa Rosa area of Sonoma County; the Bay Area (central and southern 

Alameda, Santa Clara western Stanislaus, western Merced, and the 

majority of San Benito counties); Central Valley (Yolo, Sacramento, 

Solano, eastern Contra Costa, northeast Alameda, San Joaquin, 

Stanislaus, Merced, and northwestern Madera counties); southern San 

Joaquin Valley (portions of Madera, central Fresno, and northern Tulare 

and Kings counties); Central Coast Range (southern Santa Cruz, 

Monterey, northern San Luis Obispo, and portions of western San Benito, 

Fresno, and Kern counties); and Santa Barbara County (Shaffer and 

Trenham 2002). The Sonoma County population meets the requirements of 

our Distinct Population Segment policy and therefore can be separated 

from the remainder of the population in making this determination.

    Issue 26: One commenter stated that much of the area defined as 

potential range of the Sonoma County California tiger salamander was 

based on soil types.

    Our Response: The distribution of the Sonoma County California 

tiger salamander corresponds to the distribution of specific soil 

types. The known breeding sites of the animal in Sonoma County are 

restricted to Huichica-Wright-Zamora and Clear Lake-Reyes soils series/

associations as defined by the USDA (1972, 1990). The poorly drained 

soils in the Huichica-Wright-Zamora association are considered prime 

soils for containing wetlands, and more specifically, prime soils for 

habitat containing California tiger salamander (P. Northen, pers. 

comm., 2002). The Huichica-Wright-Zamora association is restricted to 

the Santa Rosa Plain and the vicinity of the town of Sonoma (USDA 1972, 

1990). The poorly drained soils in the Clear



[[Page 13508]]



Lake-Reyes association are considered suitable to marginal soils for 

containing wetlands or habitat for California tiger salamander (P. 

Northen, pers. comm., 2002). The Clear Lake-Reyes association is found 

from the Cotati region south and east of Petaluma to the tidelands of 

northern San Francisco Bay where the salt marsh habitat is unsuitable 

for the California tiger salamander. There are also scattered areas of 

the Clear Lake-Reyes association found south and southwest of the town 

of Sonoma (USDA 1972, 1990). There are no known records of the 

California tiger salamander from the area around the town of Sonoma (D. 

McGriff, pers. comm., 2002), and there is now extensive urban and 

agricultural development in this portion of the county.



Peer Review



    In accordance with our July 1, 1994, Interagency Cooperative Policy 

for Peer Review in Endangered Species Act Activities (59 FR 34270), we 

solicited the expert opinions of 12 independent specialists regarding 

pertinent scientific or commercial data and assumptions relating to the 

taxonomy, population status, and supporting biological and ecological 

information for the California tiger salamander in Sonoma County. The 

purpose of such review is to ensure that listing decisions are based on 

scientifically sound data, assumptions, and analyses, including input 

of appropriate experts and specialists. Information and suggestions 

provided by the reviewers were incorporated or addressed as applicable.

    We received peer reviews from five of the experts. All of them 

agreed the Sonoma County California tiger salamander is imperiled 

throughout all or a portion of its range. One reviewer provided 

references on threats from disease the reviewer believed relevant to 

our final rule decision. This peer reviewer also stated that threats 

from disease are much more severe for small populations. Another peer 

reviewer recommended a number of editorial clarifications in the 

emergency and proposed rules. The third peer reviewer stated that the 

California tiger salamander should be listed throughout its range. A 

fourth peer reviewer provided additional information on the California 

tiger salamander, and the fifth peer reviewer, based on years of field 

work, agreed that the Sonoma County California tiger salamander is 

endangered.



Summary of Factors Affecting the Species



    Section 4 of the Act and regulations (50 CFR part 424) promulgated 

to implement the listing provisions of the Act describe the procedures 

for adding species to the Federal list. We may determine a species to 

be endangered or threatened due to one or more of the five factors 

described in section 4(a)(1). These factors, and their application to 

the Sonoma County California tiger salamander, are as follows:



A. The Present or Threatened Destruction, Modification, or Curtailment 

of Its Habitat or Range



    The Sonoma County California tiger salamander population, as well 

as the population in Santa Barbara County, which we listed as 

endangered (65 FR 57242, September 21, 2000), are considered to be the 

most vulnerable of the six populations of the California tiger 

salamander (LSA Associates, Inc. 2001; Shaffer and Trenham 2002). Urban 

development is the primary threat to the Sonoma County California tiger 

salamander. The DPS now occurs in scattered, and increasingly isolated, 

breeding sites within a small portion of its historic range on the 

Santa Rosa Plain in Sonoma County. Five known breeding sites of this 

DPS have been destroyed in the last 2 years. All of the eight known 

remaining breeding sites are distributed in the City of Santa Rosa and 

immediate associated unincorporated areas, an area approximately 8 km 

(5 mi) long by 6 km (4 mi) wide. Within this area and south to the 

Cotati area, there are scattered records of adult salamanders crossing 

roads during the fall and winter rains, and also sporadic instances of 

breeding in roadside ditches and low-quality pools. However, these 

roadside ditches and low-quality pools likely do not represent viable 

breeding sites because they either do not have sufficient ponding 

duration and/or associated uplands for estivation.

    The eight known breeding sites are imperiled by the construction of 

high-density housing, office buildings, roads, and other development. 

The survival and viability of the Sonoma County California tiger 

salamander is directly related to availability of breeding pools with 

hydrological and other factors conducive to the salamander's 

reproduction. There also must be adequate upland acreage, with 

associated small mammal burrows, in the vicinity of the Sonoma County 

California tiger salamander breeding pools to accommodate estivation. 

The Santa Rosa Plain once contained extensive valley oak woods, native 

grasslands, riparian, and vernal pools (1942 aerial photographs on file 

with Dr. Phil Northen at California State University at Sonoma). Vernal 

pools and seasonal wetlands likely were extensive, due to the flat 

terrain, clay soils, and relatively high rainfall (CH2M Hill 1995). 

Based on the topography and habitat type of the lands that have been 

converted to urban development and agriculture on the Santa Rosa Plain, 

the number of breeding ponds, the extent of upland habitats, and the 

quality of the remaining habitats has been greatly reduced since 

Europeans first settled the region.

    The extent of the historic range of the California tiger salamander 

within the Santa Rosa Plain in Sonoma County is uncertain due to 

limited information collected on this population prior to the 1990s 

(Shaffer et al. 1993; Jennings and Hayes 1994). However, based on the 

habitat requirements of the species for low elevation, seasonally 

filled breeding ponds and small rodent burrows, the ecology of the 

taxon, the general trend of urban development into suitable and 

occupied habitat, and other adverse factors affecting the species, we 

believe that it once occupied a more extensive, but still limited area 

within the Santa Rosa Plain.

    A 1990 study of the Santa Rosa Plain found that 25 percent of an 

11,300-ha (28,000-ac) study area had been converted to subdivisions, 

``ranchettes,'' golf courses, and commercial buildings (Waaland et al. 

1990). An additional 17 percent of the study area had been converted to 

agricultural uses. Since 1990, many more acres have been urbanized and 

converted to intensive agriculture, particularly vineyards. Even 

relatively minor habitat modifications, such as construction of roads, 

storm drains, and road curbs that traverse the area between breeding 

and estivation sites, increase habitat fragmentation, impede or prevent 

migration, and result in direct and indirect mortality of California 

tiger salamanders (Mader 1984; S. Sweet, in litt. 1993, 1998; Findlay 

and Houlahan 1996; Launer and Fee 1996; Gibbs 1998). All of the 

remaining known Sonoma County California tiger salamander breeding 

pools are within 450 m (1,476 ft) of roads and residential development, 

and five of the eight remaining viable breeding locations are within 

100 m (328 ft) of major development activities.

Urban Development

    Urban development poses a significant threat to all of the known 

breeding sites of the Sonoma County California tiger salamander. Six of 

these



[[Page 13509]]



sites are found in and around the former Air Center that is located in 

southwest Santa Rosa. This area contains one of the largest undeveloped 

blocks of land within the city limits of Santa Rosa. Urban development 

is proposed on or near locations containing four of the eight known 

breeding sites in the Santa Rosa area (EIP Associates 1994, 2000). The 

airport was closed and the property sold to the City of Santa Rosa in 

the mid-1980s. The City of Santa Rosa is proposing the majority of the 

area be developed as part of their Southwest Area Plan (EIP Associates 

1994, 2000).

    Urban development of the Santa Rosa area is proceeding rapidly. 

Demographic data obtained from the City of Santa Rosa Housing and 

Community Development Commission indicate that, since 1980, Santa Rosa 

has experienced a greater than 53 percent increase in its population. 

From 1980 until 1997, the number of housing units grew by 66 percent 

from 35,403 units in 1980 to 53,558 units by January 1, 1997 (M. 

Enright, pers. comm., 2001).

    Five known breeding sites were lost within the past 2 years, two of 

which were lost due to commercial development with another lost to 

urban development/housing. In June 2002, a fourth breeding site near 

Cotati was destroyed when the pond was filled for unknown reasons (D. 

Cook, in litt., 2002; L. Davis, pers. comm., 2002). The Cotati location 

was considered highly productive for salamanders (D. Cook, in litt., 

2002). A fifth, and previously unknown, breeding site near Cotati was 

destroyed shortly after the emergency listing went into effect (67 FR 

47726) (D. Wooten, Service, pers. comm., 2002). We were not aware of 

this occurrence at the time the emergency rule was published. 

Salamander larvae were found in a roadside ditch that backed up onto a 

large pool on private property (CNDDB 2002). It is likely this pool 

served as the breeding site for salamanders in this area. This site was 

located in an area where road sightings of tiger salamanders commonly 

occurred in absence of a known breeding site. The pool was drained 

without appropriate authorizations under County of Sonoma ordinances 

(P. Shannin, U.S. Army Corps of Engineers (Corps), pers. comm., 2002; 

P. Stamp, Sonoma County Planning Department, pers. comm., 2002).

Roads and Highways

    California tiger salamanders require a large amount of barrier-free 

landscape for successful migration (Shaffer et al. 1993; Loredo et al. 

1996). Roads and highways are permanent physical obstacles that can 

block the animals from moving to new breeding habitat, or prevent them 

from returning to their breeding ponds or estivation sites. Road 

construction can reduce or completely eliminate the viability of a 

breeding site, and in some cases, larger portions of a metapopulation.

    All the pools at the known extant Sonoma County California tiger 

salamander breeding sites are within 450 m (1,476 ft) of roads of 

various sizes. Findlay and Houlahan (1996) found that roads within 

2,000 m (1.2 mi) of wetlands adversely affected the number of amphibian 

species. At this time, it is still possible for salamanders at breeding 

sites associated with the Air Center to migrate to the FEMA/Broadmore 

North Preserves. A proposed through-street and high-density housing 

will eliminate this migration corridor, leading to fragmentation and 

further isolation of remaining breeding sites. If this planned through-

street and accompanying high-density housing are completed, only three 

breeding sites will remain where salamanders can access more than one 

breeding pool without crossing roads.

    Large numbers of California tiger salamanders at some locations in 

the Central Valley, up to 15 or 20 per mile of road (J. Medeiros, 

Sierra College, pers. comm., 1993), have been killed as they crossed 

roads on breeding migrations (Hansen and Tremper 1993; S. Sweet, in 

litt., 1993). Estimates of losses to automobile traffic range from 25 

to 72 percent of the breeding population for several different 

populations of the species (Twitty 1941; S. Sweet, in litt., 1993; 

Launer and Fee 1996). Curbs and berms as low as 9 to 13 cm (3 to 5 in), 

which allow salamanders to climb onto the road but can restrict or 

prevent their movements off the roads, can turn the roads into sources 

of high mortality (Launer and Fee 1996; S. Sweet, in litt., 1998). 

Automobile traffic along Stony Point Road in western Santa Rosa has 

probably quadrupled in the past 5 years (D. Cook, pers. comm., 2002). 

This was once a moderately used rural road which is now a major route 

for commuter traffic. Between November 21, 2001, and December 5, 2001, 

26 California tiger salamanders were found killed by cars on this road 

between Santa Rosa and Cotati. Fourteen of these dead California tiger 

salamanders were found along Stoney Point Road near Meachum Road (D. 

Cook, pers. comm., 2002). The Engel Preserve is adjacent and north of 

Todd Road. A proposed road widening project along Todd Road would 

likely increase traffic and result in an increased threat of roadkill 

for salamanders migrating between the Engel Preserve and salamander 

estivation habitat south of Todd Road.

Description of the Breeding Sites

    (1) Hall Road Preserve: This 74-ha (183-ac) site is owned by CDFG. 

It is the largest preserved area where the Sonoma County California 

tiger salamander is currently known to occur. It contains two pools 

with ponding levels adequate for successful breeding during drought 

years. This preserve contains seven additional breeding pools that are 

relatively shallow and do not pond water long enough for successful 

breeding in years of moderate to low rainfall. Surveys conducted over 

the past 2 years indicate this preserve does not function as a highly 

productive breeding site (Cook and Northern 2001). The land surrounding 

the preserve is privately owned, and the City of Santa Rosa has issued 

permits for urban development. Urban development has occurred on 

adjacent lands to the east and west, and agriculture to the north of 

the preserve. Exotic predators of the salamander, such as Louisiana 

crayfish (Procrambus clarkii), stickleback fish (Gasterosteus 

aculeatus), and possibly bullfrogs (Rana catesbeiana) are present at 

the Hall Road Preserve.

    (2) FEMA/Broadmore North Preserves: This breeding site consists of 

two properties, the FEMA Preserve and the Broadmore North Preserve. The 

24-ha (59-ac) FEMA Preserve is owned by CDFG and contains one of the 

most productive Sonoma County California tiger salamander breeding 

sites. The 6.5-ha (16-ac) Broadmore North Preserve is a conservation 

area that was set aside as mitigation by the Bellvue School District. 

It is also managed by CDFG. The two breeding sites are contiguous and 

encompass 30 ha (75 ac) containing three breeding pools. The FEMA 

Preserve has two large, deep pools that remain ponded late in the 

season. Salamanders probably breed there during most years. The one 

breeding pool on Broadmore North is shallow and does not contribute 

salamanders to the population in dry years (i.e., there is no 

recruitment) (D. Cook, pers. comm., 2001). While there is no 

hydrological connection between this site and the deeper pools 

contained on the FEMA Preserve, the FEMA Preserve probably allows the 

salamanders at the Broadmore North Preserve the opportunity to breed 

during dry years. Urban development has occurred to the north and east 

sides of the preserves. Although these breeding sites are protected, 

urbanization imperils upland habitats on private land to the east and 

west of them. A new road and housing development on lands adjacent to 

the



[[Page 13510]]



preserves' western boundaries have been permitted by the City of Santa 

Rosa and are now partially constructed. This new road and construction 

has partially blocked the western migration route between breeding 

pools at the Air Center and the pools at the FEMA and Broadmore North 

preserves. Planned future phases of this project, also permitted by the 

City of Santa Rosa, will totally block migration between the FEMA/

Broadmore North Preserves and the Air Center.

    (3) Engel Preserve: This is a 16-ha (40-ac) privately owned 

preserve that contains approximately 7 ha (18 ac) of wetlands. Three 

pools appear to have ponding levels adequate for salamander breeding in 

normal to dry rainfall years. Sonoma County California tiger 

salamanders were not documented at this site prior to the 2001/2002 

rainy season. Based on the small number of larvae found at this site, 

however, it is likely that there are low numbers of salamanders 

inhabiting this site. Todd Road runs along the southern boundary of 

this site and automobile traffic poses a threat to salamanders 

migrating between the Engel Preserve and estivation sites to the south.

    (4) Northwest Air Center: This breeding site contains one breeding 

pond and is located on private land. Much of the associated upland has 

recently been developed. This site is bordered on the west and north by 

roads subject to heavy traffic from housing developments that have been 

constructed under the City of Santa Rosa's Southwest Area Development 

Plan. Housing has eliminated migration routes to the east and south, 

thus leaving this site as an isolated breeding site with less than 22 

ha (55 ac) of remaining undeveloped upland area and pool with private 

lands surrounding it to the south and east (M. Enright, pers. comm., 

2001).

    (5) Southwest Air Center: This breeding site is located on private 

land and contains one breeding pool. The City of Santa Rosa has issued 

permits for a residential development that likely will result in the 

elimination of salamanders at this location. Preparation of this site 

for construction was initiated, but further development has been 

delayed as a result of the emergency listing of this species. The 

salamanders at this location also may utilize the breeding ponds at the 

FEMA/Broadmore North preserves by an existing migration corridor to the 

east. The destruction of this breeding site likely will further isolate 

the animals inhabiting this location. Loss of this breeding site will 

contribute to the overall isolation of the remaining breeding sites.

    (6) North Air Center: There is one breeding pool on this privately 

owned site. Recent residential and commercial developments that border 

the breeding site on three sides severely restrict the potential for 

migration. The City of Santa Rosa has approved residential and road 

projects for this location that will adversely affect the salamanders. 

This site is bordered by houses to the west, a road with high levels of 

automobile traffic to the north, and a corporate park to the east. 

There is a small tract of undeveloped private land to the south. No 

protection exists for the uplands or breeding pool which is located 

directly south of Sebastopol Road. The upland area is about 15 ha (37 

ac). Portions of Sebastopol Road have been widened to four traffic 

lanes, including the construction of storm drains and curbs. The curbs 

likely funnel migrating salamanders into storm drains where they perish 

after being washed into the sewer system. Residential and commercial 

projects currently are under construction in this area. The City of 

Santa Rosa has issued permits for the development of this site, and the 

Corps has requested formal consultation from us for the fill of this 

breeding site. Development plans will also result in the loss of 

estivation habitat. Preparation of this site for construction was 

initiated, but further development has been delayed as a result of the 

emergency listing of this species.

    (7) Wright Avenue: This breeding site is located on private land. 

Approved development described in the City of Santa Rosa's Southwest 

Area Development Plan will isolate this breeding site through increased 

automobile traffic and residential development along Wright and Ludwig 

Avenues. No construction is specifically proposed for this property, 

but no protection exists to prevent the breeding site and associated 

uplands from being developed. This site is on agricultural lands, and 

access has not been allowed for several years. Thus, the condition, or 

even the continued existence of this pool, cannot be confirmed.

    (8) South Ludwig Avenue: This breeding site is located on private 

land, and current threats to the salamanders include increased traffic 

along Ludwig Avenue due to increasing residential development. The 

breeding site and associated uplands are currently not protected from 

potential development. This site is on agricultural lands, and access 

has not been allowed for several years. Thus, the condition, or even 

the continued existence of this pool cannot be confirmed.

Conclusion for Factor A

    Except for the Hall Road Preserve, all of the known breeding sites 

of the Sonoma County California tiger salamander are found on small 

locations in areas being rapidly converted from low-intensity farming, 

cattle grazing, and low-density housing, to high-density housing and 

office buildings. Only three breeding sites (the Hall Road Preserve, 

FEMA/Broadmore North Preserve, and Engel Preserve) have hydrologic 

regimes adequate to provide recruitment for Sonoma County California 

tiger salamanders in normal to dry years. Five of the breeding sites 

are on private property. Two of the breeding sites on private lands are 

on agricultural lands where access for salamander surveys has not been 

allowed in recent years. Thus, it is unknown if these two breeding 

sites still have Sonoma County California tiger salamanders, or if they 

retain hydrological features required for successful salamander 

breeding. Four of the breeding locations associated with the old 

airfield in southwest Santa Rosa are slated for development, which will 

disrupt the hydrology of the surrounding uplands by altering natural 

runoff. If plans for the development of the area in the vicinity of 

these four breeding sites are completed, there will be no migratory 

corridors remaining between any of the currently extant breeding 

locales.

    Maintenance of tracts of habitat between breeding sites will likely 

play a pivotal role in maintenance of the Sonoma County California 

tiger salamander metapopulation dynamics. If breeding sites are 

eliminated and the metapopulation becomes so fragmented that 

individuals are unable to disperse between suitable patches of habitat, 

the probability of natural recolonization will not offset the 

probability of extinction. Some of the salamander breeding sites, such 

as the FEMA Preserve/ Broadmore North Preserve and the pools associated 

with the Air Center, are linked to each other by suitable habitat. If 

movements through these linkages are disrupted or precluded (e.g., by 

urban development), then the stability of the metapopulation (i.e., the 

exchange of individuals between breeding sites) will be affected. 

Isolation, whether by geographic distance or ecological factors, will 

prevent the influx of new genetic material, and likely to result in 

inbreeding and eventual extinction (Levin 2002). We believe that the 

Sonoma County California tiger salamander is at risk from increasing



[[Page 13511]]



fragmentation and isolation caused by urban development.



B. Overutilization for Commercial, Recreational, Scientific, or 

Educational Purposes



    In the past, the larvae of non-native tiger salamanders could 

legally be used as bait by fishermen in California. The extent of the 

use of the Sonoma County California tiger salamander is unknown. The 

California Code of Regulations (2002) now specifies that no salamander 

may be used as bait and excludes the California tiger salamander from a 

list of salamanders, newts, toads, and frogs that may legally be taken 

and possessed under authority of a sportfishing license. The success of 

these present regulations in avoiding or reducing recreational harvest 

of the California tiger salamander is unknown.

    Tiger salamanders are generally thought to make good pets by 

amateur herpetologists (Porras 2002). The Sonoma County California 

tiger salamander does not appear to be particularly popular among 

amphibian and reptile collectors. However, Federal listing could raise 

the value of the species within wildlife trade markets, and increase 

the threat of unauthorized collections above current levels (K. 

McCloud, Special Agent, Service, pers. comm., 2002). Even limited 

interest in the species could pose a serious threat to the DPS.



C. Disease or Predation



Disease

    Relatively little is known about the diseases of wild amphibians 

(Alford and Richards 1999). The specific effects of disease on the 

Sonoma County California tiger salamander are not known and the risks 

to the animal have not been determined. However, it is known that mass 

mortalities of amphibians from disease are not uncommon, and may be 

either a natural phenomenon of the biology of species or induced by 

anthropogenic agents (Corn 1994). In California, large numbers of dead 

and dying California tiger salamanders were observed in a pond in the 

Los Alamos Valley in Santa Barbara County, but the cause was not 

determined (S. Sweet, pers. comm., 1998).

    Worthylake and Hovingh (1989) described repeated die-offs of tiger 

salamanders (A. tigrinum) at Desolation Lake in the Wasatch Mountains 

of Utah. Affected salamanders had red, swollen hind legs and vents, and 

widespread hemorrhage of the skin and internal organs. The researchers 

determined that the die-offs were due to infection from the bacterium 

Acinetobacter, or redleg disease. The number of Acinetobacter in the 

lake increased with increasing nitrogen levels as the lake dried. The 

nitrogen was believed to come from both atmospheric deposition and 

waste from sheep grazing in the watershed (Worthylake and Hovingh 

1989). Acinetobacter, which appears to affect amphibians whose immune 

systems have been weakened by stress (Corn 1994) or another bacterial 

infection, was also the suspected cause of larval tiger salamanders 

deaths in Arizona (Collins et al. 1988, as cited in Corn 1994). 

Acinetobacter is common in soil and animal feces.

    Lefcort et al. (1997) found that tiger salamanders raised in 

natural and artificial ponds contaminated with silt were susceptible to 

infection by the water mold Saprolegnia parasitica at a location in 

Georgia. This fungus first appeared on the feet, spread to the entire 

leg, and then infected animals died. Die-offs of western toads (Bufo 

boreas), Cascades frogs (Rana cascadae), and Pacific treefrogs also 

have been associated with Saprolegnia infections (Kiesecker and 

Blaustein 1997). Saprolegnia is widespread in natural waters and 

commonly grows on dead organic material (Wise et al. 1995). Saprolegnia 

ferax outbreaks have been identified as a cause of high amphibian 

embryo mortalities in the Pacific Northwest (Kiesecker et al. 2001).

    Viruses associated with die-offs of tiger and spotted salamanders 

in Maine and North Dakota have been isolated (B. McLean, National 

Wildlife Health Center, in litt., 1998). Also, Jancovich et al. (1997) 

isolated a virus, believed to be an iridovirus, as the primary pathogen 

responsible for a decimating epizootic event affecting the federally 

endangered Sonoran tiger salamander (Ambystoma tigrinum stebbinsi) in 

Arizona. Iridoviruses have recently been implicated as the cause of 

amphibian mass deaths worldwide, with novel iridoviruses identified 

from a number of regions.

    Ranaviruses are often highly virulent and cause systemic infections 

in amphibians. Epizootiology (science that deals with the character, 

ecology, and causes of outbreaks of animal diseases) of ranaviral 

disease in amphibians is poorly understood, but dissemination may be 

partly due to the virus's ability to remain infectious under adverse 

conditions and for prolonged periods. Likely modes of spread of 

amphibian ranaviruses may include use of fishing gear, including boats, 

and through artificial stocking of ponds for recreational fishing. 

Also, water birds have the potential to mechanically transfer the virus 

on their feathers, feet, or bills, or by regurgitation of ingested 

infected material. Some outbreaks of ranaviral disease in tiger 

salamanders have been associated with altered habitats and artificial 

ponds. Due to their highly virulent nature, ranaviruses should be 

considered a potential threat to amphibian populations, especially 

those isolated from previous disease outbreaks (and thus lacking 

specific immunity) and species with low fecundity (Daszak et al. 1999).

    Kiesecker et al. (2001) reported that pathogen outbreaks in 

amphibian populations in the western U.S. may be linked to climate-

induced changes in UV-B light exposure. Their findings indicate that 

climate-induced reductions in water depth at oviposition (laying of 

eggs) sites have caused high mortality of embryos by increasing their 

exposure to UV-B radiation and, consequently, their vulnerability to 

infection. Furthermore, they speculate that climate changes since the 

mid-1970s related to El Ni[ntilde]o/Southern Oscillation cycles and 

elevated sea-surface temperatures could be the precursor for pathogen-

mediated amphibian declines in many regions.

    Pathogen outbreaks have not been documented in Sonoma County 

California tiger salamanders. Nevertheless, disease must be considered 

a potential future population threat because of the relatively small, 

fragmented remaining Sonoma County California tiger salamander breeding 

sites, the many stresses on these sites due to habitat losses and 

alterations, and the many other potential disease-enhancing 

anthropogenic changes which have occurred both inside and outside of 

the range of this DPS. An amphibian pathogen could eliminate one or 

more breeding sites of this animal.

Predation

    Predation and competition by introduced or non-native species 

potentially affect all of the known Sonoma County California tiger 

salamander breeding sites. Bullfrogs prey on California tiger 

salamanders (P. Anderson 1968; Lawler et al. 1999). Morey and Guinn 

(1992) documented a shift in amphibian community composition at a 

vernal pool complex, with California tiger salamanders becoming 

proportionally less abundant as bullfrogs increased in number. Lawler 

et al. (1999) found that less than 5 percent of California red-legged 

frog (Rana aurora draytonii) tadpoles survived to metamorphosis when 

raised with bullfrog tadpoles. Moyle (1973) attributed disappearance of 

both



[[Page 13512]]



California red-legged frogs and foothill yellow-legged frogs (Rana 

mucosa) within the San Joaquin Valley of California to habitat 

alteration coupled with predation and competition from bullfrogs. 

Although bullfrogs are unable to establish permanent breeding 

populations in unaltered vernal pools and seasonal ponds, dispersing 

immature bullfrogs take up residence in such water bodies during winter 

and spring where they prey on native amphibians, including larval 

salamanders (Morey and Guinn 1992; Seymour and Westphal 1994).

    Because bullfrogs are known to travel at least 2.6 km (1.6 mi) from 

one pond to another (Bury and Whelan 1984), they have the potential to 

naturally colonize new areas where they do not currently exist, 

including ponds where Sonoma County California tiger salamanders occur. 

In one study of the eastern San Joaquin Valley, 22 of 23 (96 percent) 

ponds with California tiger salamanders were within the bullfrogs' 

potential dispersal range (Seymour and Westphal 1994). In addition, 

because bullfrogs are still sought within California for sport and 

food, and may be taken without limit under a fishing license, the 

threat of transport for intentional establishment in new locations 

where California tiger salamanders exist or could exist is significant.

    One of the pools at the Hall Road breeding site, and two of the 

pools contained at the FEMA/Broadmore North preserves, are located 

within 46 m (150 ft) of ditches or creek channels known to contain 

bullfrogs or crayfish. Bullfrogs likely occur in Roseland Creek, which 

is near the FEMA/Broadmore North preserve and breeding sites associated 

with the Air Center (D. Cook, pers. comm., 2002). Bullfrogs are likely 

present in ditches that cross the Hall Road Preserve (D. Cook, pers. 

comm., 2002). The direct and indirect evidence thus indicates that non-

native bullfrogs represent a continuing significant threat to the 

persistence of the Sonoma County California tiger salamander.

    Western mosquitofish (Gambusia affinis) are native to central North 

America (watersheds tributary to the Gulf of Mexico) and have been 

introduced throughout the world for mosquito control, including in 

California beginning in 1922. Western mosquitofish now occur throughout 

California wherever the water does not get too cold for extended 

periods, and they are still widely planted throughout the State (Boyce, 

UCD, in litt., 1994) by about 50 local mosquito abatement districts.

    Salamanders may be especially vulnerable to western mosquitofish 

predation due to their fluttering external gills, which may attract 

these visual predators (Graf and Allen-Diaz 1993). Loredo-Prendeville 

et al. (1994) found no California tiger salamanders inhabiting ponds 

containing western mosquitofish. Western mosquitofish prey on other 

amphibian species, such as the California newt (Taricha torosa) 

(Gamradt and Kats 1996) and Pacific treefrog (Goodsell and Kats 1999) 

tadpoles in both field and laboratory experiments, even given the 

optional prey of mosquito larvae (Goodsell and Kats 1999; L. Kats, 

Pepperdine University, pers. comm., 1999). Mosquitofish have also been 

observed ingesting and then spitting out California newt larvae, 

causing severe damage to the newts in the process (Graf and Allen-Diaz 

1993). Given the effects of western mosquito fish on other amphibian 

species, they are likely to have similar effects on California tiger 

salamanders. If they have the same effects, the use of mosquito fish in 

California tiger salamander habitat threatens the persistence of the 

species, especially in the isolated Sonoma County California tiger 

salamander population.

    Other non-native fish have either been directly implicated in 

predation of California tiger salamanders or appear to have the 

potential for such. For example, introductions of sunfish species 

(e.g., largemouth bass (Micropterus salmoides) and bluegill (Lepomis 

macrochirus)), catfish (Ictalurus spp.), and fathead minnows 

(Pimephales promelas) are believed to have eliminated California tiger 

salamanders from several breeding sites in Santa Barbara County 

(Service 2000). Non-native sunfish species, catfish, and bullheads 

(Ameiurus spp.) have been, and still are, widely planted in ponds in 

California to provide for sportfishing. By 1984, the California fish 

fauna included about 50 such transplanted and exotic species, mostly 

from eastern North America origin (Hayes and Jennings 1986). More 

recently, Moyle (2002) estimated that, on average, California is losing 

about one native species or subspecies of fish every 5 to 6 years, and 

gaining an average of one alien species about every 2 years.

    Non-native fish introductions may be responsible for the declines 

of frog species in western North America (Hayes and Jennings 1986). 

Such introduced fish may be a problem for California raids because of 

their specialization for preying on aquatic life (including eggs and 

larvae), and because the affected amphibians may have evolved under 

conditions of limited fish predation, which now increases the impacts 

of such introductions (Hayes and Jennings 1986). We believe the same 

threat applies to the California tiger salamander. Thus, potential 

introduction of such non-native fish species in Sonoma County 

California tiger salamander breeding habitat should be considered a 

threat to the persistence of this DPS.

    The degree to which predation from native fish have affected the 

Sonoma County California tiger salamanders is unknown. For example, 

sticklebacks (Gasterosteus spp.), which have been present in California 

for at least 16 million years, were believed to be the factor 

preventing the Sonoma County California tiger salamander from 

establishing at a site in Sonoma County (Cook and Northen 2001). One 

pool at the Hall Road Preserve appears to have all of the biological 

components for successful California tiger salamander breeding, but has 

a small connector to a drainage ditch containing stickleback. Sonoma 

County California tiger salamanders have never been found at this site, 

and it is suspected that predation of their eggs and larvae by this 

fish is the limiting factor (D. Cook, pers. comm., 2002).

    Non-native and native crayfish (Pacifastacus, Orconectes, and 

Procambarus spp.) apparently prey on California tiger salamanders 

(Shaffer et al. 1993) and may have eliminated some populations 

(Jennings and Hayes 1994). Crayfish prey on California newt eggs and 

larvae, despite toxins produced by these amphibians, and they may be a 

significant factor in the loss of newts from several streams in 

southern California (Gamradt and Kats 1996). These crayfish have been 

found at both the FEMA/Broadmore North and Hall Road Preserves. At the 

FEMA property, crayfish were found in the pool (D. Cook, pers. comm., 

2002). The crayfish likely came from the adjacent Roseland Creek 

Channel. Louisiana crayfish have been found in the ditches that cross 

the Hall Road Preserve, but not at any of the pools known to support 

Sonoma County California tiger salamander populations (D. Cook, pers. 

comm., 2002). The presence of both stickleback and crayfish, along with 

the suspected presence of bullfrogs, could negatively affect Sonoma 

County California tiger salamanders within the Hall Road Preserve.

    California tiger salamanders are also likely preyed on by many 

native species of fish and wildlife. In healthy salamander populations, 

such predation is probably not a significant threat. But when combined 

with other impacts,



[[Page 13513]]



such as predation by non-native species, contaminants, migration 

barriers, or habitat alteration, it may cause a significant decrease in 

population viability. Native predators include herons and egrets, 

western pond turtles (Clemmys marmorata), various garter snakes 

(Thamnophis spp.), larger California tiger salamanders, larger 

spadefoot toads (Scaphiopus hammondii), and California red-legged frogs 

(M. Peters, Service, in litt., 1993; Hansen and Tremper 1993). In 

Arizona, larval tiger salamanders are preyed upon by adult predaceous 

diving beetles (Dytiscus dauricus) (Holomuzki 1986), and turkey 

vultures (Carthartes aura) have been observed feeding on larval or 

adult tiger salamanders (Duncan 1999).



D. The Inadequacy of Existing Regulatory Mechanisms



    The primary cause of the decline of the Sonoma County California 

tiger salamander is the loss, degradation, and fragmentation of habitat 

due to human activities. Federal, State, and local laws have been 

insufficient to prevent past and ongoing losses of the limited habitat 

of the Sonoma County California tiger salamander.

Federal

    Clean Water Act. Under section 404 of the Clean Water Act (CWA) (33 

U.S.C. 1344 et seq.), the U.S. Army Corps of Engineers (Corps) 

regulates the discharge of fill material into waters of the United 

States, including wetlands. Section 404 regulations require applicants 

to obtain a permit for projects that involve the discharge of fill 

material into waters of the United States, including wetlands. However, 

normal farming activities are exempt under the CWA and do not require a 

permit (53 FR 20764; Robert Wayland III, Environmental Protection 

Agency (EPA), in litt., 1996). Projects that are subject to regulation 

may qualify for authorization to place fill material into headwaters 

and isolated waters, including wetlands, under several nationwide 

permits. The use of nationwide permits by an applicant or project 

proponent is normally authorized with minimal environmental review by 

the Corps. No activity that is likely to jeopardize the continued 

existence of a threatened or endangered species, or that is likely to 

destroy or adversely modify designated critical habitat of such 

species, is authorized under any nationwide permit. An individual 

permit may be required by the Corps if a project otherwise qualifying 

under a nationwide permit would have greater than minimal adverse 

environmental impacts.

    Recent court cases may further limit the Corps' ability to utilize 

the CWA to regulate the fill or discharge of fill or dredged material 

into the aquatic environment within the current range of the Sonoma 

County California tiger salamander (Solid Waste Agency of Northern Cook 

County v. U.S. Army Corps of Engineers, 531 U.S. 159 (2001) (SWANCC)). 

The effect of SWANCC on Federal regulation of activities in wetlands in 

the area of the Sonoma County California tiger salamander has recently 

become clear by the Corps' failure to assert its jurisdiction over fill 

of several wetlands within the range of the Sonoma County California 

tiger salamander. In a letter from the Corps dated March 8, 2002, 

concerning the fill of 0.18 ha (0.45 ac) of seasonal wetlands southwest 

of the intersection of Piner and Marlow Roads (Corp File Number 

19736N), the Corps referenced the SWANCC decision and reiterated that 

the subject wetlands were not ``waters of the United States'' because 

they were: (1) Not navigable waters; (2) not interstate waters; (3) not 

part of a tributary system to 1 or 2; (4) not wetlands adjacent to any 

of the foregoing; and (5) not an impoundment of any of the above. The 

letter further stated that the interstate commerce nexus to these 

particular waters is insufficient to establish CWA jurisdiction and, 

therefore, not subject to regulation by the Corps under section 404 of 

the CWA. The Corps also cited the SWANCC decision as their reasoning 

for not taking jurisdiction over fill of Sonoma County California tiger 

salamander breeding pools at the recently constructed South Sonoma 

Business Park.

    When on- or off-site mitigation is required by the Corps as a 

condition of a section 404 permit to fill certain wetlands, there is 

often low probability that affected Sonoma County California tiger 

salamander habitat values, if any, would actually be compensated and 

replaced by the ensuing mitigation action(s). A 1994 Service study of 

selected wetlands re-creation projects in California authorized through 

the section 404 program found deficiencies in both compliance and 

performance of the re-created wetlands (Santa Rosa Plain Vernal Pool 

Ecosystem Preservation Plan 1995). There was evidence that, of all the 

proposed mitigation, half of the sites were meeting less than 75 

percent of the mitigation conditions and our goal for ``in-kind'' 

replacement was not being met (DeWeese 1994). Other recent studies have 

produced similar results. In addition, most wetland re-creation efforts 

in California to date have been directed at the wetlands themselves and 

have not adequately addressed the upland and other related needs of 

California tiger salamanders.

    Semlitsch (1998) examined published literature for six species of 

pond-breeding ambystomatid salamanders from five States and concluded 

that a buffer zone encompassing 95 percent of a given population would 

need to extend 263 m (534 ft) from a wetland's edge into surrounding 

terrestrial habitat in order to give adequate protection. More 

recently, Trenham (2001), although cautioning that essential 

terrestrial habitats and buffer requirements are still relatively 

poorly understood, concluded that plans to maintain local populations 

of California tiger salamanders should include pond(s) surrounded by 

buffers at least 173 m (567 ft) wide of terrestrial habitat occupied by 

burrowing mammals. Management plans that focus only on preserving ponds 

or wetlands--without consideration for associated terrestrial habitat--

are likely to fail to maintain viable amphibian populations (Marsh and 

Trenham 2001). However, even with inclusion of terrestrial habitat 

buffers, recent studies have demonstrated that restored wetlands are 

often still only partially successful in recolonization by the full 

amphibian assemblages being targeted for restoration (Lehtinen and 

Galatowitsch 2001; Pechmann et al. 2001). Successful compensatory 

mitigation for losses of California tiger salamander pool and pond 

habitat due to filling would also require the connectivity of the 

restoration site to other pools and ponds (Gibbs 1998; Lehtinen et al. 

1999; Trenham et al. 2001; Marsh and Trenham 2001). Pond isolation may 

be an important consideration in disturbed environments where inter-

pond dispersal is impeded by barriers such as roads and urban 

development (Marsh and Trenham 2001). The California tiger salamander 

may also require large preserves to maintain viable breeding 

populations and to allow recolonizations from natural and anthropogenic 

local extirpations (P. Northen, in litt., 2001).

    Three federally endangered plants, Sonoma sunshine (Blennosperma 

bakeri), Sebastopol meadowfoam (Limnanthes vinculans), and Burke's 

goldfields (Lasthenia burkei) occur on the Santa Rosa Plain of Sonoma 

County in the vicinity of the Sonoma County California tiger 

salamander. However, little overlap occurs between the viable breeding 

sites of this species and these federally listed vernal pool species. 

Any Corps consultation requirement for fill



[[Page 13514]]



of pools on the Santa Rosa Plain would be triggered by the listed 

plants. Since the salamander and the federally listed plants do not 

substantially overlap, salamander breeding pools are unlikely to be 

protected by presence of the plants or their habitat. Furthermore, even 

if breeding pools of this animal are avoided due to the presence of a 

federally listed plant species, this protection may only extend to the 

pool itself with a small upland buffer. Since Sonoma County California 

tiger salamanders spend up to 80 percent of their life in small mammal 

burrows in upland habitats surrounding breeding pools, the protection 

of the pool itself, with concurrent loss of uplands surrounding the 

pool, would still result in the loss of local Sonoma County California 

tiger salamander breeding sites.

    We conclude that regulation of wetlands filling by the Corps under 

section 404 of the CWA is inadequate to protect the Sonoma County 

California tiger salamander from further decline. Section 404 

implementation fails to prevent losses of numerous small wetlands in 

California that may support California tiger salamander breeding. 

Section 404 does not regulate the continuing losses of California tiger 

salamander terrestrial habitat (except to the extent certain 

agricultural activities may be regulated). When authorized fills under 

section 404 do result in compensatory mitigation for wetlands losses, 

it is unlikely that California tiger salamander habitat losses at 

specific fill sites can, and will be, fully and successfully mitigated.

State

    Since 1994, the CDFG recognizes the California tiger salamander as 

a ``species of special concern'' by the CDFG. More recently, the 

California tiger salamander has been placed on the State's list of 

protected amphibians, which means that it cannot be taken without a 

special permit issued for scientific collecting or research. Also, as 

stated earlier, the California Code of Regulations (2002) specifies 

California tiger salamanders can no longer be taken, possessed, or used 

for fishing bait. However, any more stringent protection of California 

tiger salamanders or their habitat, as would be provided under a CESA 

listing or designation as a Fully Protected species by CDFG, is 

lacking.

    CDFG recognizes the importance of California tiger salamander 

conservation at the local population level, and routinely considers and 

recommends actions to mitigate potential adverse effects to the species