Endangered and threatened species: Findings on petitions, etc.— Lost River sucker and shortnose sucker; 5-year status review,

[Federal Register: July 21, 2004 (Volume 69, Number 139)]

[Proposed Rules]

[Page 43554-43558]

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

[DOCID:fr21jy04-29]

DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

Endangered and Threatened Wildlife and Plants; Notice of Revised 90-Day Petition Finding and Initiation of a 5-Year Status Review of the Lost River Sucker and Shortnose Sucker

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Notice of a revised 90-day petition finding and initiation of a 5-year status review.

SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a revised 90-day finding for a petition to remove the Lost River sucker (Deltistes luxatus) and shortnose sucker (Chasmistes brevirostris) throughout their ranges from the Federal List of Threatened and Endangered Wildlife and Plants (List), pursuant to the Endangered Species Act (Act) (16 U.S.C. 1531 et seq.). We find that the petition does not present substantial scientific or commercial information indicating that delisting of the Lost River and shortnose suckers may be warranted. As a result of the 1995, 1996, and 1997 fish die-offs, the endangered suckers experienced significant losses of thousands of adult suckers and have not recovered. Although the petition and information in our files do not provide new information relevant to the status of the Lost River and shortnose suckers, we are initiating a 5- year review of these species under section 4(c)(2)(A) of the Act to consider any new information that has become available as a result of recent actions to reduce threats to the species, and to provide the States, tribes, agencies, university researchers, and the public an opportunity to provide information on the status of the species. We are requesting any new information on the Lost River and shortnose suckers since their original listing as endangered species in 1988 (53 FR 27130).

DATES: The finding announced in this document was made on July 14, 2004. To be considered in the 5-year review, comments and information should be submitted to us by October 31, 2004.

ADDRESSES: Data, information, written comments and materials, or questions concerning this finding and 5-year review should be submitted to the Field Supervisor, Klamath Falls Fish and Wildlife Office, U.S. Fish and Wildlife Service, 6610 Washburn Way, Klamath Falls, Oregon 97603. The petition finding, supporting data, and comments are available for public inspection, by appointment, during normal business hours at the above address.

FOR FURTHER INFORMATION CONTACT: Curt Mullis, Field Supervisor, at the above address, or at 541-885-8481.

SUPPLEMENTARY INFORMATION:

Background

Section 4(b)(3)(A) of the Act requires that the Service 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. To the maximum extent practicable, we must make the finding within 90 days of receipt of the petition, and the finding is to be published promptly in the Federal Register. If we find substantial information exists to support the petitioned action, we are required to promptly commence a review of the status of the species, if one has not already been initiated (50 CFR 424.14). ``Substantial information'' is defined as ``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)). Petitioners need not prove that the petitioned action is warranted to support a ``substantial'' finding; instead, the key consideration in evaluating a petition for substantiality involves demonstration of the reliability of the information supporting the action advocated by the petition (USFWS 1995).

The factors for listing, delisting, or reclassifying a species are described at 50 CFR 424.11. We may delist a species only if the best scientific and commercial data available substantiate that it is neither endangered nor threatened. Delisting may be warranted as a result of: (1) Extinction; (2) recovery; and/or (3) a determination that the original data used for classification of the species as endangered or threatened were in error.

A petition to delist the Lost River sucker and shortnose sucker, dated September 12, 2001, was submitted by Mr. Richard A. Gierak, representing Interactive Citizens United. Three other similar petitions were received and treated as comments on Mr. Gierak's petition. On May 14, 2002, the Service published its initial finding that the petitions to delist the Lost River and shortnose suckers did not present substantial scientific or commercial information indicating that delisting the suckers may be warranted (67 FR 34422). On June 12, 2002, Walt Moden, Merle Carpenter, Charles Whitlatch, John Bair, Tiffany Baldock, and Dale Cross filed a complaint in Federal District Court alleging that our initial finding on the petition to delist the Lost River sucker and shortnose sucker was arbitrary and capricious and violated the Act (Moden v. U.S. Fish and Wildlife Service). On September 3, 2003, the court ruled that our finding was arbitrary and capricious because it reached unexplained conclusions not supported by the administrative record. The court remanded the initial finding, and ordered us to either reissue the

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initial finding with further explanation or proceed to a status review. Consistent with the court's order, the Service has rewritten the original finding, clarifying our analysis as well as addressing additional comments made by the court and the petitioners.

Species Information

The Lost River sucker and shortnose sucker are two fishes that naturally occur only in the upper Klamath Basin of southern Oregon and northern California. Both species primarily reside in lake habitats and spawn in tributary streams or at springs and shoreline areas within Upper Klamath Lake. Historically, the two species were very numerous in shallow lakes that occurred in the upper basin and made spawning migrations up the rivers of the Upper Klamath basin. Concentrations of migrating and spawning suckers were exploited as a food source by Native Americans and white settlers. The habitat of the two species has been highly modified, owing to water development projects, and has contributed to their listing (USFWS 1998).

The Lost River sucker and shortnose sucker are long-lived species, reaching ages of over 30 years. Also, both species are highly fecund, being capable of producing larger numbers of eggs, and are more tolerant of poor water quality conditions than trout (USFWS 2001). These factors should make the suckers adaptable to drought and other adverse conditions (USFWS 1992). However, because current water quality conditions in Upper Klamath Lake and other areas are so adverse, there is considerable mortality. Few young suckers are produced during drought years and there is a regular order-of-magnitude decrease in juvenile sucker numbers from summer to fall. For successful recruitment to occur, young fish must survive to spawn, but substantial recruitment of subadult fish into the spawning population has been rare (USFWS 2001). In a 2002 biological opinion, the Service examined data relevant to recruitment and found: ``The available data show evidence for relatively substantial recruitment of smaller fish into the Williamson River population of Lost River sucker and shortnose sucker in only a few of the last eighteen years.'' The data also show that there is substantial recruitment into the shoreline spawning population of Lost River suckers for only a few of the last fifteen years (USFWS 2002). Also, there is apparently low survivorship over the first winter, suggesting that fall/winter survival is low (USFWS 2002). Die-offs in 1995, 1996, and 1997 have killed many of the older fish, thus reducing the ability of the populations to reproduce. Over 6,000 dead adult suckers were collected following a 1996 fish die-off, and this figure likely represented only a small fraction of the total that died (USFWS 2001). Following the 1995 through 1997 fish die-offs, the Sprague River spawning index declined 80 to 90 percent for the two suckers (USFWS 2001). Therefore, current conditions, including poor water quality and low lake levels resulting from drought, pose a serious risk to even tolerant and adaptive fish like suckers. (The spawning index is an indicator of the relative number of suckers that migrate in the Sprague River during the spring spawning period. Nets to survey suckers are put in the river weekly over the entire spawning season. The index is calculated by taking the average number of suckers caught per day per net and summing the averages over the season. While the spawning index is not necessarily the most accurate measure of population size, because individual suckers may not spawn every year and the capture efficiency of nets can be affected by water clarity, currents, debris loading, and other factors, it is a good indicator of trends when measured over a long period of time. Therefore, current conditions, including poor water quality and low lake levels resulting from drought, pose a serious risk to even tolerant and adaptive fish like suckers.

The two sucker species were federally listed as endangered in 1988 (53 FR 27130). The original listing and status assessments conducted in 2001 and 2002 and included in two biological opinions on the operations of the Bureau of Reclamation's Klamath Project (USFWS 2001, 2002) concluded that the suckers were still subject to the following threats: (1) Drastically reduced adult populations and reduction in range; (2) extensive habitat loss, degradation and fragmentation; (3) small or isolated adult populations; (4) isolation of existing populations by dams (passage); (5) poor water quality leading to large fish die-offs and reduced fitness; (6) lack of sufficient recruitment; (7) entrainment into irrigation and hydropower diversions; (8) hybridization with the other native Klamath sucker species; (9) potential competition with introduced exotic fishes; and (10) lack of regulatory protection from Federal actions that might adversely affect or jeopardize the species. These status assessments drew upon information from all published and unpublished reports on the biology, distribution, and status of the listed sucker species in the Klamath region and the ecosystem on which they depend. The assessments also included and considered new information that was available.

Discussion of Petition

The petition states that delisting of the Lost River and shortnose suckers should occur because, either: (1) The estimates of the sucker populations in the 1980s were in error and did not, in fact, demonstrate a precipitous decline (i.e., sucker populations in the 1980s were much larger than assumed); or (2) the estimates of the sucker populations in the 1980s were reasonably accurate, and the suckers have demonstrated an enormous boom in the period since listing and no longer exhibit ``endangered'' status (i.e., sucker populations have increased and are no longer endangered).

The petition's supporting documentation consists of an excerpt (four pages and ``Figures 2 & 3'') from testimony by David A. Vogel before the U.S. House Committee on Resources (Vogel 2001), five bibliographic references, and eight footnotes. The referenced testimony concerns sucker population estimates from the 1950s to 1997, which are included in the petition as a table labeled ``Figure 2.'' Figure 2 provides selective information for the two sucker species from three time periods: pre-1980s (1950s-1976), 1980s, and 1990s (see Table 1 below). While this table displays population estimates that are higher since listing, we find that comparisons of population sizes pre- and post-listing using these data are invalid because: (1) Data were obtained using different methods and models, and assumptions used by those models were violated; and (2) the estimates do not refer to the same populations. These limitations are explained below.

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Table 1.--Estimated Lost River and Shortnose Sucker Populations From Petition Figure 2

Species

1950s-early 1960s

1970

1976

1984 1985 1986

1987

1996 1997

Lost River Sucker................... Unknown................. Unknown................ Unknown................ 23,123 11,861 6,000 Unknown................ 94,000 46,000 Shortnose Sucker.................... Extremely low (