Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List the Mountain Whitefish (Prosopium williamsoni) in the Big Lost River, ID, as Threatened or Endangered, 59983-59989 [E7-20767]

Agencies

• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 72, Number 204 (Tuesday, October 23, 2007)]
[Proposed Rules]
[Pages 59983-59989]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E7-20767]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17


Endangered and Threatened Wildlife and Plants; 90-Day Finding on 
a Petition To List the Mountain Whitefish (Prosopium williamsoni) in 
the Big Lost River, ID, as Threatened or Endangered

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Notice of 90-day petition finding.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a 
90-day finding on a petition to list the mountain whitefish (Prosopium 
williamsoni) occurring in the Big Lost River in Idaho as threatened or 
endangered under the Endangered Species Act of 1973, as amended (Act). 
We find that the petition does not present substantial scientific or 
commercial information indicating that listing the mountain whitefish 
in the Big Lost River may be warranted. This finding is based on 
insufficient information indicating that mountain whitefish in the Big 
Lost River may represent a species, subspecies, or distinct population 
segment (DPS) and, therefore, a listable entity under section 3(16) of 
the Act. Accordingly, we will not be initiating a status review in 
response to this petition. However, we ask the public to submit to us 
any new information that becomes available concerning the status of 
mountain whitefish occurring in the Big Lost River at any time. This 
information will help us to monitor and encourage the ongoing 
conservation of mountain whitefish in the Big Lost River.

DATES: The finding announced in this document was made on October 23, 
2007. You may submit new information concerning the mountain whitefish 
occurring in the Big Lost River for our consideration at any time.

ADDRESSES: Submit data, information, comments, and materials concerning 
this finding to the Supervisor, Snake River Fish and Wildlife Office, 
1387 S. Vinnell Way, Boise, ID 83709. The supporting file for this 
finding is available for public inspection, by appointment, during 
normal business hours at the above address.

FOR FURTHER INFORMATION CONTACT: Jeffery Foss, Field Supervisor, Snake 
River Fish and Wildlife Office (see ADDRESSES); telephone 208-378-5243; 
facsimile 208-378-5262. If you use a telecommunications device for the 
deaf (TDD), please call the Federal Information Relay Service (FIRS) at 
800-877-8339.

SUPPLEMENTARY INFORMATION:

Background

    Section 4(b)(3)(A) of the Act requires that we make a finding on 
whether a petition to list, delist, or reclassify a species presents 
substantial scientific or commercial information indicating that the 
petitioned action may be warranted. Such findings are based on 
information contained in the petition, supporting information submitted 
with the petition, and information otherwise readily available in our 
files at the time we make the determination. To the maximum extent 
practicable, we are to make this finding within 90 days of our receipt 
of the petition, and publish a notice of the finding promptly in the 
Federal Register.
    Our standard for substantial scientific or commercial information, 
as defined by the Code of Federal Regulations (CFR), with regards to a 
90-day petition finding is ``that amount of information that would lead 
a reasonable person to believe that the measure proposed in the 
petition may be warranted'' (50 CFR 424.14(b)). If we find that the 
petition presents substantial scientific or commercial information, we 
are required to promptly commence a status review of the species.
    We base this finding on information provided by the petitioner that 
we determined to be reliable after reviewing sources referenced in the 
petition and information readily available in our files at the time of 
the petition review. We evaluated this information in accordance with 
50 CFR 424.14(b). Our process for making this 90-day finding under 
section 4(b)(3)(A) of the Act and Sec.  424.14(b) of our regulations is 
limited to a determination of whether the information in the petition 
meets the ``substantial information'' threshold. A substantial finding 
should be made when the Service deems that adequate and reliable 
information has been presented that would lead a reasonable person to 
believe that the petitioned action may be warranted.
    On June 15, 2006, we received a petition, dated June 14, 2006 
(hereafter cited as `Petition' 2006), from the Western Watersheds 
Project ('petitioner'). The petitioner requested that mountain 
whitefish in the Big Lost River, Idaho, be listed as threatened or 
endangered in accordance with section 4 of the Act. The petitioner also 
requested that critical habitat be designated. The petition clearly 
identified itself as such and included the requisite identification 
information for the petitioner, as required in title 50 of the Code of 
Federal Regulations (CFR), 424.14(a). In an August 21, 2006 letter to 
the petitioner, we acknowledged receipt of the petition, and explained 
that we would not be able to address the petition at that time due to 
other priorities relating to court orders and litigation settlement 
agreements. We further indicated that we had reviewed the petition and 
determined than an emergency listing was not necessary.
    The petition requested that we list the mountain whitefish in the 
Big Lost River of Idaho as a separate species, subspecies, or in the 
alternative as a distinct population segment. The petition contends 
that mountain whitefish occupying the Big Lost River have experienced 
``a population decline and extirpation, and a decreased range.'' 
Threats identified in the Big Lost River include ``loss and degradation 
of habitat due to irrigation diversions, livestock grazing, off-road 
vehicle use, roads; and predation, competition, and disease from non-
native fish species.'' The petition asserts that this situation is in 
contrast to other populations of mountain whitefish in other drainages.
    The petition was accompanied by a single document, the ``Big Lost 
River Mountain Whitefish Status Report,''

[[Page 59984]]

prepared by Ecosystem Sciences Foundation and dated February 2006 
(hereafter cited as `ESF Status Report 2006'). This report contained 
information related to the taxonomy, life history, demographics, 
genetics, habitat, threats, and the past and present distribution of 
mountain whitefish in the Big Lost River. The petition incorporated by 
reference any citations used in the ESF Status Report 2006, but did not 
provide actual copies of those references.

Species Information

    Mountain whitefish (Prosopium williamsoni) are members of the 
Salmonidae family and are found throughout mountainous areas of western 
North America in Canada and the United States. In the United States, 
the species is known to occur in the States of Washington, Oregon, 
Idaho, Wyoming, Montana, Colorado, Utah, Nevada, and California 
(NatureServe 2007). Mountain whitefish are relatively common and 
widespread in most river basins in Idaho (American Fisheries Society 
2007). Their preferred habitat is cold water streams and lakes in 
western North America, and typically third or fourth order streams (Van 
Kirk et al. 2003, p. 8).
    While the majority of populations of mountain whitefish occur in 
riverine environments, some populations are restricted to lakes or 
isolated sink basins. Mountain whitefish in the Big Lost River reside 
in a ``sink'' drainage which was once part of a large Pleistocene lake 
system that included Lake Terreton (Van Kirk et al. 2003, p. 6). As the 
waters receded, the Big Lost River and four adjacent drainages lost 
their surface connection to the Snake River, resulting in five isolated 
sink drainages in Idaho.
    There are additional populations of mountain whitefish that occur 
in other sink drainages, such as tributaries in the Lahontan Basin in 
California and Nevada and the Bonneville Basin in Utah. Populations in 
these basins are similar to the population in the Big Lost River in 
that all are relict populations of mountain whitefish that formerly 
resided in large Pleistocene lake systems that are now closed basins.
    Mountain whitefish in the Big Lost River are thought to be most 
closely related to populations that occur in the upper Snake River 
based on genetic data from Whiteley et al. (2006) and Campbell and 
Cegelski (2005). The species most likely entered the Big Lost River 
approximately 10,000 years ago (Van Kirk et al. 2003, p. 8). Today, 
mountain whitefish in the Big Lost River are physically isolated from 
other populations within the Snake River basin.
    Mountain whitefish, also known as mountain herring, are about 57 
centimeters (cm) (22 inches (in)) in length. The general body shape is 
slender with a somewhat round cross section, and body coloration is 
typically silver on the sides, dusky olive green or blue on the back, 
and the belly is a dull white (Simpson and Wallace 1982, p. 77). It has 
been suggested that individuals from the Big Lost River appear to be 
different from other populations of mountain whitefish in coloration 
and body shape, but data to confirm this observation has not yet been 
collected (A. Whiteley, pers. comm. 2007a).
    The spawning season for mountain whitefish is in the fall, and is 
correlated with stream temperature (Simpson and Wallace 1982, p. 77; 
Wydoski 2001, p. 694). Unlike other salmonids, mountain whitefish are 
broadcast spawners in which a nest or redd is not created; females 
scatter eggs and the males fertilize them (McGinnis 1984, p. 137).
    Mountain whitefish are thought to be opportunistic bottom feeders 
that consume whatever is in abundance, including fish eggs during the 
spawning season (McGinnis 1984, p. 137). It is known to actively feed 
on both aquatic and terrestrial insects, but is also a piscivore (eats 
other fish) (NatureServe 2007). Mountain whitefish reach sexual 
maturity at 3 to 4 years, and have been observed to live up to 12 years 
(Wydoski 2001, p. 694).

Listable Entity Evaluation

    In making a 90-day finding on a petition to list a species, we must 
first establish that the subject of the petition may constitute a 
``species'' under section 3(16) of the Act. In this case, the 
petitioner has requested that the mountain whitefish occupying the Big 
Lost River in Idaho be listed as a separate species, subspecies, or in 
the alternative, as a distinct population segment. For vertebrates, the 
Act allows listing of these three entities (16 U.S.C. 1532(16)).

Evaluation of the Mountain Whitefish in the Big Lost River as a Species 
or Subspecies

    The mountain whitefish in the Big Lost River of Idaho are currently 
recognized as members of the single species Prosopium williamsoni, 
which is considered common and widespread throughout the mountainous 
western United States northward into Canada (NatureServe 2007). The 
mountain whitefish in the Big Lost River are not recognized as a 
separate species or subspecies by the American Fisheries Society 
(Nelson et al. 2004, p. 86), nor by the Integrated Taxonomic 
Information System (2007). The State of Idaho does not consider the 
mountain whitefish occupying the Big Lost River to be either a 
significant species or a species of concern (Idaho Comprehensive 
Wildlife Strategy 2005).
    The petitioner's arguments for the recognition of mountain 
whitefish in the Big Lost River as a species, subspecies or distinct 
population segment (discussed separately, below), rely primarily on the 
analysis of molecular data. Because of the complex and highly technical 
nature of molecular analysis, we consulted with a fisheries genetics 
expert within the Service to assess the petitioner's assertions to the 
potential significance of the genetics information presented. Dr. 
Donald E. Campton, Senior Scientist at the U.S. Fish and Wildlife 
Service's Abernathy Fish Technology Center and former President of the 
Genetics Section of the American Fisheries Society, served as our 
consultant on this finding.
    The petitioner contends that ``the best available science 
demonstrates that the Big Lost River Mountain Whitefish should be 
protected as a separate species or subspecies of whitefish because all 
genetic analyses demonstrate that it is genetically unique--so much so 
that the genetic distance observed between Big Lost River mountain 
whitefish and surrounding populations is at least as large as that seen 
between other subspecies or even species. [ESF] Status Report [2006], 
pp. 6, 14-15.'' The ESF Status Report 2006, p. 6 cites Whiteley and 
Gamett (2002) for the basis of this assertion. Whiteley and Gamett 
(2002) is an abstract of a presentation given at the Sinks Symposium of 
the Idaho Chapter of the American Fisheries Society in February 2002 
(Van Kirk et al. 2003, p. 13).
    We contacted Mr. Gamett to determine whether any written document 
was available reflecting the content of that presentation, but found 
that the abstract was the only written record. The Symposium 
Proceedings (Van Kirk et al. 2003) were available to us in our files. 
The abstract does not state that ``the genetic distance is at least as 
large as that seen between other subspecies or even species,'' but 
rather that ``consideration of the Big Lost River mountain whitefish as 
a separate subspecies may be warranted.'' This appears to represent the 
personal opinions of the presenting researchers, no data are presented 
to support the petitioner's claim regarding genetic distance, and the 
ESF Status Report

[[Page 59985]]

2006 cited by the petitioner appears to have overstated the conclusions 
of Whiteley and Gamett (2002).
    Data available in our files from a 2005 Idaho Department of Fish 
and Game Report do not support the contention that mountain whitefish 
found in the Big Lost River are genetically equivalent to a subspecies 
or species. In analyzing the sequence divergence of mitochondrial DNA 
between whitefish populations, Campbell and Cegelski (2005, Figure 3) 
found that the percent sequence divergence of mountain whitefish from 
the Big Lost River compared to other populations within the Upper Snake 
River Basin ranged from 0.33 to 0.49 percent. The authors note that, 
for comparison purposes, sequence divergence between recognized 
subspecies of cutthroat trout range (Oncorhynchus clarki lewisi and O. 
c. bouvieri) from 1.4 to 1.9 percent, and sequence divergence between 
different species of trout (O. mykiss and O. clarki) range from 4.0 to 
4.5 percent (Campbell and Cegelski 2005, p. 6); these are far higher 
levels of mtDNA sequence divergence than was observed between mountain 
whitefish in the Big Lost River and other populations within the Upper 
Snake River assemblage. According to this report, the genetic distance 
between mountain whitefish in the Big Lost River and surrounding 
populations is far less than that observed between other subspecies or 
species of salmonids. Furthermore, several other populations of 
mountain whitefish examined by Campbell and Cegelski (2005, Figure 3) 
exhibited levels of divergence equal to or greater than that exhibited 
by fish from the Big Lost River (the Boise River populations, for 
example). This issue is discussed in further detail in the distinct 
population segment analysis presented below.
    The petitioner's citation of pages 14-15 of the ESF Status Report 
2006 in support of their contention that mountain whitefish in the Big 
Lost River merit consideration as a separate species or subspecies 
apparently refers to several different statements and sources, 
beginning with the citation of Whiteley (2002) as stating that ``the 
Big Lost [mountain whitefish] should be considered as a separate group. 
This group is highly genetically differentiated from all other 
populations analyzed to date'' (ESF Status Report 2006, p. 15).
    The ESF Status Report 2006 presented only conclusions from the 
Whiteley 2002 reference, but provided no data or analysis to support 
those conclusions. Only the name of the author, a title, and the name 
of a genetics laboratory in the Biological Sciences Department at the 
University of Montana was provided under the Whiteley 2002 citation 
(ESF Status Report 2006, p. 18) and we were unable to locate a 
publication by that name through a search of the published literature. 
We therefore contacted Mr. Whiteley and asked for a copy of the 
referenced publication. Mr. Whiteley informed us that the document 
cited was an unpublished report to a funding agency (A. Whiteley, pers. 
comm. 2007b), and referred us to a recently published, peer-reviewed 
paper on the genetics of mountain whitefish (Whiteley et al. 2006, 
already contained in our files and discussed further below). In 
responding to us, Mr. Whiteley also stated that he believes that 
mountain whitefish in the Big Lost River are more divergent than two 
other ``species'' of whitefish, Prosopium spilonotus and P. abyssicola 
(A. Whiteley, 2007b; quotes from author's original communication). 
However, Mr. Whiteley went on to indicate that the classification of 
these mountain whitefish species is not clearly defined (that they may 
not be ``good'' species; A. Whiteley, 2007b, quotes from author's 
original communication) and subject to debate.
    The petitioner further references the following statements: ``In 
analysis of all the genetic information available at that time, Gamett 
et al. (2004) concluded that Big Lost River whitefish are genetically 
different from all other whitefish and they are likely a unique species 
or subspecies of fish,'' and ``Given the most recent genetic studies of 
Miller et al. (2005) and Campbell et al. (2005), all of which confirm 
past studies and conclusions--the Big Lost mountain whitefish must be 
managed as a separate species from all other mountain whitefish'' (ESF 
Status Report 2006, p. 15). The Gamett et al. (2004) citation appears 
to be a reference to an oral presentation made at a meeting of the 
Idaho Fish and Game Commissioners (ESF Status Report 2006, p. 16), and 
it was therefore unavailable to us. The citations for both Miller et 
al. (2005) and Campbell et al. (2005) appear to be references to 
abstracts, papers, or posters presented at a meeting of the American 
Fisheries Society and were not available to us.
    In our files we had a recent publication, W, Whiteley et al. 
(2006), regarding the genetics of mountain whitefish which was not 
cited in the ESF Status Report 2006. In this publication, the 
researchers utilized both allozymes and microsatellites to examine the 
genetic structure of mountain whitefish populations throughout the 
northwestern United States and British Columbia, plus two populations 
from western Alberta. The results indicated three large-scale genetic 
assemblages of mountain whitefish in this region based on allozyme 
data, and five large-scale genetic assemblages based on the 
microsatellite data (Whiteley et al. 2006, p. 2778).
    The Big Lost River population was included within the resulting 
Upper Snake River assemblage in both cases and is described as the 
``most genetically divergent'' site in that assemblage. However, the 
data indicate that the degree of genetic divergence of mountain 
whitefish in the Big Lost River from other populations in the upper 
Snake River region is substantially less than the genetic divergence 
observed between the major assemblages. The authors note low levels of 
within-population genetic variation in several physically isolated 
populations of mountain whitefish, including not only the Big Lost 
River, but also the Big Wood River, Bull River, and Thutade Lake 
(Whiteley et al. 2006, p. 2780). They also note a higher degree of 
genetic differentiation in several physically isolated sites in the 
Upper Snake region, which is to be expected when gene flow is precluded 
geographically. In addition to the Big Lost River, this pattern was 
observed in the Henry's Fork and several Bonneville Basin sites 
(Whiteley et al. 2006, p. 2781).
    This most recent analysis of the genetic relationships of mountain 
whitefish (Whiteley et al. 2006) does not support the contention that 
mountain whitefish of the Big Lost River are distinctive or unique 
genetically as compared to other populations in the upper Snake River 
assemblages, or as compared to populations within other assemblages 
relative to the rest of the species. Rather, the authors point to a 
high degree of genetic differentiation between many populations of 
mountain whitefish in the Upper Snake River due to the topography of 
the region, and characterize those populations as ``more finely 
subdivided than elsewhere'' (Whiteley et al. 2006, p. 2781). The 
authors also point out that the degree of genetic differentiation 
observed in mountain whitefish among tributaries within river basins is 
less than that observed in populations of other salmonids, such as bull 
trout (Salvelinus confluentus) and westslope cutthroat trout 
(Oncorhynchus clarki lewisi) (i.e., bull trout and westslope cutthroat 
trout show greater levels of genetic differentiation between 
populations within river basins than do mountain whitefish) (Whiteley 
et al. 2006, p. 2783). Despite this high degree of

[[Page 59986]]

genetic structuring, it has not been suggested in literature, that each 
of these bull trout or westslope cutthroat trout populations be 
considered as separate subspecies or species. The mountain whitefish in 
the Big Lost River exhibit less genetic differentiation than these 
populations.
    Also referenced by the petitioner in the ESF Status Report 2006 is 
the statement that ``Whitefish in the Big Lost River are fixed for 
microsatellite alleles that are rare or not present in the surrounding 
rivers'' (ESF Status Report 2006, p. 15). The petition cites Whiteley 
and Gamett (2002), which is the previously mentioned abstract from a 
meeting of the Idaho Chapter of the American Fisheries Society (Van 
Kirk et al. 2003, p. 13), available to us in our files. It refers to 
``the fixation of a unique allele in the Big Lost River population at 
one of the microsatellite loci.'' The ESF Status Report 2006 implies 
that there are multiple rare or unique microsatellite alleles in the 
Big Lost River population, when in fact the abstract indicates there 
was only one unique allele.
    Although we were not provided with the data to support this 
statement, even if we assume that one microsatellite allele has become 
fixed in mountain whitefish occupying the Big Lost River, that 
information does not in and of itself confer any biological or 
ecological importance (e.g., as measured by morphological, 
physiological, or behavioral traits) because microsatellite alleles are 
considered selectively neutral, the frequencies of which largely 
reflect random or stochastic processes (e.g., genetic drift, population 
bottlenecks, founder effects, mutation rates) rather than selection for 
traits that confer increased fitness (Ashley and Dow 1994, p. 185). 
Indeed, the total lack of variability observed in microsatellites 
sampled for mountain whitefish in the Big Lost River (Whiteley et al. 
2006, p. 2775) indicates that this population has likely undergone a 
past population bottleneck relative to other populations with a 
subsequent loss of genetic variability and random fixation (e.g., via 
drift of a unique [or nearly unique] allele) (D. Campton, pers. comm. 
2007). Under such conditions, genetic distance may increase quickly, 
but is not in and of itself indicative of biological significance 
(Hedrick 1999, pp. 315, 316).
    We have no information, and the petitioner has offered none, to 
indicate that the fixation of this single microsatellite allele may in 
any way be biologically important or significant to the taxon as a 
whole. Such fixed allelic differences between geographically isolated 
freshwater populations of salmonid fishes are not considered uncommon 
(Allendorf and Waples 1996, p. 257).
    In sum, mountain whitefish occurring in the Big Lost River are not 
currently recognized as a subspecies or species (Nelson et al. 2004, p. 
86; ITIS 2007), and neither the information provided in the petition 
nor in our files suggest that mountain whitefish in the Big Lost River 
may represent a distinct species or subspecies. Even considering the 
additional information supplied by Mr. Whiteley, our conclusion remains 
the same. Although no universally accepted definition of species and 
subspecies exists, in general such classifications are based on 
multiples lines of evidence, including factors such as morphology, 
behavior, and genetic characters (Haig et al. 2006, p. 1586). 
Information in our files indicates that the genetic distance observed 
between mountain whitefish in the Big Lost River and surrounding 
populations is substantially less than that observed between other 
subspecies or species of salmonids (Campbell and Cegelski 2005, p. 6).
    Likewise, the petition provides no substantial information to 
support its assertion that the mountain whitefish in the Big Lost River 
constitute a genetically unique stock; although the population 
possesses one unique haplotype, almost every population sampled had at 
least one unique haplotype, and some had several (Campbell and Cegelski 
2005, Table 1). All available evidence indicates that there is a high 
degree of genetic structuring between populations of mountain 
whitefish, as is frequently observed in populations of freshwater 
salmonids (Allendorf and Waples 1996, p. 257; Whiteley et al. 2006, p. 
2783), but that the degree of genetic differentiation between mountain 
whitefish in the Big Lost River and surrounding populations is no 
greater than that observed between other populations of mountain 
whitefish (Whiteley et al. 2006, p. 2781; Campbell and Cegelski 2005, 
Figure 3, p. 5).
    Although mountain whitefish in the Big Lost River may be 
genetically differentiated from other populations of the species, the 
data demonstrate that the same can be said of many populations of 
whitefish throughout the species' range; this widespread genetic 
structuring of populations alone does not indicate that each of these 
individual populations may warrant consideration as a separate 
subspecies or species (Haig et al. 2006, p. 1588). We conclude that the 
petitioner did not present substantial information indicating that 
mountain whitefish in the Big Lost River may be a species or 
subspecies.

Evaluation of Mountain Whitefish in the Big Lost River as a Distinct 
Population Segment

    Under the Act, we can consider for listing any species, subspecies, 
or distinct population segment (DPS) of any species of vertebrate fish 
or wildlife that interbreeds when mature (16 U.S.C. 1532(16)). The 
petitioner has asked us to consider listing mountain whitefish 
occurring in the Big Lost River of Idaho as a DPS. We, along with the 
National Marine Fisheries Service, developed the Policy Regarding the 
Recognition of Distinct Vertebrate Population Segments (DPS Policy) 
(February 7, 1996, 61 FR 4722) to help us in determining what qualifies 
as a DPS under the Act. The policy identifies three elements that are 
to be considered in a decision regarding the status of a possible DPS 
as endangered or threatened under the Act:
    1. Discreteness of the population segment in relation to the 
remainder of the species to which it belongs;
    2. The significance of the population segment to the species to 
which it belongs; and
    3. The population segment's conservation status in relation to the 
Act's standards for listing.
Discreteness
    The petitioner asserts that the mountain whitefish occupying the 
Big Lost River basin are discrete due to the terminal nature of the Big 
Lost River within a sink drainage and the isolation of this population. 
Our DPS policy states that a population segment of a vertebrate species 
may be considered discrete if it is markedly separated from other 
populations of the same taxon as a consequence of physical, 
physiological, ecological, or behavioral factors. We agree that 
mountain whitefish in the Big Lost River may be considered discrete, 
since they occur in a closed basin lacking a surface connection to any 
major river system and are therefore physically separated from the 
remainder of the populations in the taxon. We therefore conclude that 
there is substantial information indicating that mountain whitefish in 
the Big Lost River may satisfy the discreteness criterion of the DPS 
policy.
Significance
    If a population segment is considered discrete, our DPS policy 
directs us to consider available scientific evidence of the importance 
of this discrete population to the remainder of the taxon (species) to 
which it belongs. The policy

[[Page 59987]]

suggests four potential factors to consider in evaluating significance:
    1. Persistence of the discrete population in an ecological setting 
unusual or unique for the taxon,
    2. Evidence that loss of the discrete population segment would 
result in a significant gap in the range of the taxon,
    3. Evidence that the discrete 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, or
    4. Evidence that the discrete population segment differs markedly 
from other populations of the species in its genetic characteristics.
    The petitioner points to two of these four factors in arguing for 
the significance of a possible DPS, contending that mountain whitefish 
occupying the Big Lost River are significant ``because it [mountain 
whitefish] exists in a unique ecological setting that has contributed 
to its genetic differentiation, and because it differs markedly in its 
genetic characteristics from other whitefish populations.'' The 
petition asserts that the Big Lost River is a unique ecological setting 
because it is one of five so-called ``sinks drainages'' that are a 
collection of closed surface drainage basins in southeastern Idaho, and 
that this physical isolation has led to genetic and other differences.
    The petitioner's argument that the mountain whitefish of the Big 
Lost River occupy a unique ecological setting relative to the rest of 
the species rests on the fact that the Big Lost River basin is a closed 
surface drainage basin. However, as noted earlier, the mountain 
whitefish also occurs in isolated populations in sink drainages in the 
Bonneville Basin in Utah and the Lahontan Basin in California and 
Nevada. Therefore, the mere fact that these mountain whitefish are 
found in a physically isolated drainage is not in and of itself unique, 
unusual, or significant to the species as a whole.
    In addition, other mountain whitefish occur in other types of 
physically isolated settings, such as above impassable waterfalls 
(e.g., Big Wood River and Henry's Fork of the Snake River in Idaho, or 
Bull River and Thutade Lake in British Columbia; Whiteley et al. 2006, 
p. 2780). The petitioner does not provide any information that the Big 
Lost river drainage is ecologically unusual or unique in any other way 
(e.g., in terms of prey species, community composition, water 
chemistry, substrate), apart from its physical isolation. As other 
populations of mountain whitefish also occur in closed drainage basins 
within the range of the species, and other populations occur within 
other physically isolated settings, the petition information does not 
indicate that the ecological setting of the Big Lost River is unique or 
unusual for the species.
    We next evaluate whether the mountain whitefish in the Big Lost 
River differ markedly from the remainder of the species in its genetic 
characteristics. The petition contends that mountain whitefish in the 
Big Lost River meet the significance criterion of the DPS policy 
``given the high level of genetic, morphological, and physical 
uniqueness of the Big Lost River Mountain Whitefish to the species as a 
whole.'' As evidence, the petitioner states that ``Big Lost River 
Mountain Whitefish are isolated and evolving separately from all other 
whitefish populations; the Big Lost River Mountain Whitefish have 
coloration and morphological differences--morphologically Big Lost 
River Mountain Whitefish are distinct from all other mountain 
whitefish; Big Lost River Mountain Whitefish are fixed for 
microsatellite alleles that are rare or not present in the surrounding 
rivers; biologically, Big Lost River Mountain Whitefish are an 
evolutionarily independent unit because they are isolated from 
surrounding populations and have been for some time; and the Big Lost 
River Mountain Whitefish is highly genetically differentiated from all 
other whitefish populations analyzed to date. [ESF] Status Report 
[2006], pp. 14-15.''
    We have already addressed in our evaluation of whether this 
population may be a separate species or subspecies, the petition's 
points regarding the fixation of a single microsatellite allele and the 
degree of genetic differentiation observed in mountain whitefish of the 
Big Lost River. In short, we concluded that the ESF Status Report 2006 
had overstated the findings of Whiteley and Gamett 2002 by implying 
that more than one microsatellite allele was fixed in this population, 
when the abstract indicates that they only detected the fixation of a 
unique allele at a single microsatellite locus. We also found that the 
petitioner had not provided substantial information to indicate that 
the fixation of this one microsatellite allele may be significant to 
the taxon as a whole, particularly since microsatellites are considered 
likely to be neutral markers (Ashley and Dow 1994, p. 185), and fixed 
allelic differences between isolated populations of freshwater fishes 
are not considered to be uncommon (Gyllensten 1985, p. 691; Allendorf 
and Waples 1996, p. 257).
    We likewise concluded that the petitioner had not provided 
substantial information indicating that the genetic distance between 
mountain whitefish in the Big Lost River and surrounding populations 
was so great as to merit classification as a separate subspecies or 
species. Here, however, we must address whether the petitioner has 
provided us with substantial information indicating that there may be 
marked genetic differences between mountain whitefish found in the Big 
Lost River and the remainder of the species such that mountain 
whitefish occurring in the Big Lost River may be considered significant 
to the taxon as a whole. The petitioner relies upon pages 14-15 in the 
ESF Status Report 2006 in support of its significance argument 
regarding the genetic status of mountain whitefish in the Big Lost 
River.
    The first part of the discussion on these pages cites the studies 
of Miller et al. (2005) and Campbell et al. (2005), neither of which 
was directly available to us. According to the ESF Status Report 2006, 
Miller et al. (2005) defined two distinct clades of mountain whitefish 
and possibly four separate species, although the four possible species 
are not identified, and Campbell et al. (2005) found evidence for three 
large genetic assemblages of mountain whitefish, but neither reference 
apparently specifically addresses mountain whitefish in the Big Lost 
River (ESF Status Report 2006, p. 14).
    The ESF Status Report 2006 also cites Whiteley (2002) as 
identifying mountain whitefish from the Big Lost River as genetically 
most similar to the Upper Snake River populations above Shoshone Falls. 
The ESF Status Report 2006 quotes from Whiteley (2002) that ``This 
group is highly genetically differentiated from all other populations 
analyzed to date. It is most genetically similar to populations from 
the upper Snake River (above Shoshone Falls) * * * These fish also have 
coloration and morphological differences, which provides additional 
evidence that they are highly differentiated from other mountain 
whitefish populations'' (ESF Status Report 2006, p. 15).
    As noted earlier, the Whiteley (2002) citation in the ESF Status 
Report 2006 does not provide a reference to any obtainable published 
work or data, and when we requested the information from the author, he 
informed us that the quotations cited in the ESF Status Report 2006 
were from an unpublished report to a funding agency, and provided us 
with a more recent published paper, Whiteley et al. (2006)

[[Page 59988]]

(A. Whiteley, pers. comm. 2007a, b). This publication was also 
available to us in our files. Similar to the described findings of 
Campbell et al. 2005, Whiteley et al. (2006) found evidence for three 
large genetic assemblages of mountain whitefish in the Pacific 
Northwest, which they termed Cascadia, the Upper Missouri, and Upper 
Snake.
    As described above, mountain whitefish in the Big Lost River were 
one of several populations included within the Upper Snake assemblage. 
Although described as the ``most genetically divergent'' site in that 
assemblage, this publication identifies several other populations of 
mountain whitefish that, due to their physical isolation, exhibit low 
levels of within-population genetic variation (Big Lost River, Big Wood 
River, Bull River, and Thutade Lake) and that demonstrate a high degree 
of genetic differentiation, presumably due to reduced gene flow as a 
result of physical barriers (Big Lost River, Henry's Fork and several 
Bonneville Basin sites) (Whiteley et al. 2006, pp. 2780-2781). Thus the 
mountain whitefish found in the Big Lost River are not particularly 
distinctive or unique genetically in relation to the species as a 
whole, as several other isolated populations of the species exhibit 
similar levels of genetic variability and differentiation.
    In a personal communication to the Service, Mr. Whiteley also 
indicated that mountain whitefish in the Big Lost River ``fall into the 
upper Snake River group and thus are not completely differentiated from 
all other whitefish populations analyzed to date'' (A. Whiteley, 
2007b). He went on to state that the degree of differentiation for 
mountain whitefish in the Big Lost River is the greatest he has 
observed, and that it is the single most divergent population from 
other nearby populations in the species' range. While we acknowledge 
that mountain whitefish in the Big Lost River may be genetically 
distinguished from other nearby populations, the petitioner provides no 
data to support the contention that this degree of divergence may be 
considered a marked level of differentiation, particularly in light of 
the fact that other populations of mountain whitefish, such as those in 
the Boise River, show a greater degree of difference, as described 
below.
    In considering the potential genetic distinctiveness of mountain 
whitefish in the Big Lost River, we evaluated the recent work of 
Campbell and Cegelski (2005), available in our files, which examined 
the phylogeography of mountain whitefish in Idaho, Utah, and Montana 
based on sequence analyses of the cytochrome-b gene of mitochondrial 
DNA (mtDNA). These data reveal that populations of mountain whitefish 
in general, and not just in the Big Lost River, are characterized by 
fixed, or nearly fixed, haplotypic differences between populations: 
Only 2 haplotypes out of 18 were shared by multiple populations 
(Campbell and Cegelski 2005, pp. 4-5).
    The possession of a unique haplotype is therefore not unique to the 
mountain whitefish of the Big Lost River; on the contrary, the 
publication by Campbell and Cegelski (2005) demonstrates that most 
populations of mountain whitefish sampled possess unique haplotypes. 
For example, in a sample of 7 individuals from the Boise River, the 
researchers identified 3 different haplotypes not observed in any of 
the 10 other populations sampled. The Big Lost River population 
possessed one unique haplotype, Haplotype 9. An analysis of the percent 
sequence divergence data presented in Figure 4 (Campbell and Cegelski 
2005, p. 6) demonstrates that Haplotype 9 in the Big Lost River 
population differs from Haplotype 8 in the Henry's Fork population by 
0.33 percent. This degree of divergence is far less than that observed 
between other populations of whitefish examined in this study, 
especially as compared to populations in the Lower Snake River 
assemblage. Haplotype 6, for example, from the Boise River, differs 
from Haplotype 5 observed within the same population by 1.49 percent.
    Campbell and Cegelski (2005) also found evidence for three broad 
genetic assemblages of mountain whitefish, which they term the Upper 
Snake River, Lower Snake River, and Upper Missouri River, and found 
that mountain whitefish from the Big Lost River, which have been 
isolated within that drainage, fall within the Upper Snake River Basin 
assemblage. The authors conclude that their results, in conjunction 
with ``previous research indicating that mountain whitefish in the Big 
Lost [River] appear to be genetically and morphologically distinct'' 
(citing Whiteley and Gamett 2003 [sic; 2002]), justify conserving the 
mountain whitefish occurring in the Big Lost River independent of other 
populations in the larger genetic assemblage to which they belong.
    We encourage the conservation of mountain whitefish and other 
native species as components of the natural biodiversity of the Big 
Lost River. However, the desirability of conserving mountain whitefish 
is not the same issue as whether the mountain whitefish found in the 
Big Lost River may qualify as a listable entity under the Act. Under 
the ``significance'' prong of the DPS policy we are required to apply a 
different and specific set of criteria. Based on the information in the 
petition and our files, we do not find substantial or reliable 
information indicating that mountain whitefish in the Big Lost River 
may be considered any more distinct genetically than any of several 
other populations of mountain whitefish examined, all of which may well 
be argued to merit conservation efforts outside of the realm of the 
Act.
    As noted above, the most recent genetic work (Whiteley et al. 2006) 
indicates that there are several physically isolated populations of 
mountain whitefish that, as expected under a scenario of reduced gene 
flow, show some divergence from their presumed common populations of 
origin. Particularly when a population has gone through a presumed 
bottleneck, as evidenced by the lack of microsatellite variation 
observed in mountain whitefish in the Big Lost River, the amount of 
genetic distance is expected to increase very quickly (Hedrick 1999, p. 
315). Such increased distance does not, however, automatically confer 
biological significance in the absence of any indication of adaptive 
differences. The research clearly indicates that throughout the 
relatively broad range sampled, most populations of mountain whitefish 
have diverged to the point of possessing unique haplotypes, and that 
other populations of mountain whitefish exhibit a greater degree of 
genetic divergence than observed in mountain whitefish from the Big 
Lost River (Campell and Cegelski 2005, Figure 3). Mountain whitefish in 
general appear to exhibit a high degree of genetic structure between 
populations, as observed in many species of freshwater fishes 
(Gyllensten 1985, p. 691; Allendorf and Waples 1996, p. 257; Whiteley 
et al. 2006, p. 2783). The petition does not provide substantial 
evidence that the mountain whitefish in the Big Lost River are any more 
different than any of several other populations of whitefish throughout 
the species' range.
    In addition to genetics, the petitioner contends that differences 
in coloration and morphology of mountain whitefish in the Big Lost 
River provide additional evidence that they are ``highly 
differentiated'' from all other populations, citing the ESF Status 
Report 2006, pp. 14-15. The ESF Status Report 2006 contains no data or 
other analysis to support its assertions regarding color and 
morphological differences, but cites Whiteley (2002) as the source of 
this information; however, as described earlier, no obtainable

[[Page 59989]]

reference is available (ESF Status Report 2006, p. 18). When we 
contacted the author and asked if he could provide us with the data 
demonstrating the referenced coloration and morphological differences. 
Mr. Whiteley replied, ``I don't have any data on morphological 
variation for whitefish from the Big Lost. The references you cite all 
go back to personal observations by myself'' (A. Whiteley, pers. comm., 
2007a).
    Although he believes that ``whitefish in the Big Lost [River] look 
different,'' Mr. Whiteley stated that ``these traits have not been 
quantified'' (A. Whiteley, pers. comm. 2007a). This suggests that the 
authors of the ESF Status Report 2006 erred in alluding to ``phenotypic 
studies'' if, in fact, they were referring to a researcher's personal 
observations (ESF Status Report 2006, p. 6). Therefore, we do not 
consider the statement in the ESF Status Report 2006 to this effect to 
be reliable.
    We accept Mr. Whiteley's description (A. Whiteley, pers. comm. 
2007a) that mountain whitefish from the Big Lost River may differ in 
color and form. However, based purely on Mr. Whiteley's opinion of the 
nature of these differences (shorter heads and possibly differing in 
body shape), we conclude that the petitioner has not provided us with 
substantial and reliable information to support the claim that the 
mountain whitefish in the Big Lost River have a ``high level of 
[genetic], morphological and physical uniqueness * * * to the species 
as a whole.'' We have no evidence before us to suggest that any 
differences in color or morphology that may exist are anything other 
than natural phenotypic variation that is often observed in different 
populations of fish.
    Natural variation in characteristics such as body shape in fish is 
commonly attributable to environmental factors, such as water 
temperature during development (e.g., Barlow 1961). Additionally, many 
fish exhibit a considerable degree of intraspecific variation in 
morphology, which has been experimentally demonstrated to be the result 
of phenotypic plasticity in response to the environment rather than a 
heritable response to selection (e.g., Mittelbach et al. 1999). Head 
depth is a common plastic trait in fish related to diet (e.g., Day et 
al. 1994). We have no information in our files, nor has the petitioner 
provided any substantial information, to suggest that any apparent 
differences in morphology or coloration of the mountain whitefish are 
in any way biologically meaningful such that they may be significant to 
the species as a whole. We also considered the additional information 
provided by Mr. Whiteley (A. Whiteley, pers. comm. 2007a). Even 
considering this additional information, our conclusion remains the 
same.
DPS Conclusion
    Our DPS policy directs us to evaluate the significance of a 
discrete population in the context of its importance to the remainder 
of the taxon. Based on an analysis of the information presented by the 
petitioner, Service staff expertise, and information within our files, 
our evaluation indicates that the genetic, morphological, and 
coloration differences cited by the petitioner do not indicate that 
mountain whitefish found in the Big Lost River may differ markedly from 
other populations of mountain whitefish such as to be significant to 
the species as a whole. Therefore, the differences do not rise to the 
level of significance under the criteria set by our DPS policy. Because 
the mountain whitefish occupying the Big Lost River fail to meet the 
significance criteria for a DPS under the policy, we have determined 
that they do not constitute a listable entity under the Act. We also 
note that the petitioner did not petition us to list the Big Lost River 
mountain whitefish on the basis of a significant portion of the 
species' range, nor did the petitioner provide specific information 
indicating that the mountain whitefish within the Big Lost River basin 
represented a significant portion of the range of the species. 
Therefore, we did not specifically analyze whether the mountain 
whitefish in the Big Lost River basin represented a significant portion 
of the range of the species.

Finding

    We have reviewed and evaluated the petition and literature cited in 
the petition in relation to information available to us. On the basis 
of this review and evaluation, we find that the petition does not 
present substantial scientific information to indicate that listing the 
mountain whitefish in the Big Lost River of Idaho may be warranted. 
This finding is based on lack of substantial information indicating 
that the mountain whitefish occurring in the Big Lost River qualify as 
a listable entity under section 3(16) of the Act. We find that mountain 
whitefish occurring in the Big Lost River do not constitute a separate 
species or subspecies, and although they may be considered discrete, 
neither the petition nor our files contain substantial information to 
indicate that this population may be biologically or ecologically 
significant according to the criteria under our DPS policy. Although we 
are not commencing a status review in response to this petition, we 
will continue to monitor the status and trends, potential threats, and 
ongoing management actions that might affect mountain whitefish in the 
Big Lost River. We encourage interested parties to continue to gather 
data that will assist with conservation of mountain whitefish in the 
Big Lost River basin. If you wish to provide information regarding 
mountain whitefish in the Big Lost River, you may submit your 
information or materials to the Field Supervisor, Snake River Fish and 
Wildlife Office (see ADDRESSES).

References Cited

    A complete list of all references cited is available on request 
from the Snake River Fish and Wildlife Office (see ADDRESSES).

Author

    The primary author of this notice is the Snake River Fish and 
Wildlife Office (see ADDRESSES).

Authority

    The authority for this action is the Endangered Species Act of 
1973, as amended (16 U.S.C. 1531 et seq.).

    Dated: October 15, 2007.
Kenneth Stansell,
Acting Director, U.S. Fish and Wildlife Service.
 [FR Doc. E7-20767 Filed 10-22-07; 8:45 am]
BILLING CODE 4310-55-P