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Proposed Rule

Endangered and Threatened Wildlife and Plants; Status of the Rio Grande Cutthroat Trout

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Information about this document as published in the Federal Register.

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This document has been published in the Federal Register. Use the PDF linked in the document sidebar for the official electronic format.

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Fish and Wildlife Service, Interior.


Notice of intent to initiate a status review.


We, the U.S. Fish and Wildlife Service (Service), announce our intent to initiate a candidate status review for the Rio Grande cutthroat trout (O ncorhynchus clarki virginalis) to determine if candidate status is warranted. The Endangered Species Act of 1973, as amended (Act), requires that we identify species of wildlife and plants that are endangered or threatened, based on the best available scientific and commercial information. Through the Federal rulemaking process, we add these species to the List of Endangered and Threatened Wildlife at 50 CFR 17.11 or the List of Endangered or Threatened Plants at 50 CFR 17.12. As part of this program, we maintain a list of species that we regard as candidates for listing. A candidate is one for which we have on file sufficient information on biological vulnerability and threats to support a proposal to list as endangered or threatened but for which preparation and publication of a proposal is precluded by higher-priority listing actions. During or prior to April 2008, we will make a determination concerning the results of the status review for the Rio Grande cutthroat trout, and, shortly thereafter, we will publish this determination in the Federal Register.


We will accept comments and information from all interested parties for our use in the status review and in preparing a revised finding until July 6, 2007.


If you wish to comment, you may submit your comments and materials by any of the following methods:

1. You may mail or hand-deliver your written comments and information to Wally “J” Murphy, Field Supervisor, U.S. Fish and Wildlife Service, New Mexico Ecological Services Field Office, 2105 Osuna NE, Albuquerque, New Mexico 87113.

2. You may fax your comments to Wally “J” Murphy, Field Supervisor, New Mexico Ecological Services Field Office, at (505) 346-2542.

3. You may send comments by electronic mail (e-mail) to

4. You may go to the Federal eRulemaking Portal: Follow the instructions for submitting comments. In the event that our Internet connection is not functional, please submit your comments by one of the alternate methods mentioned above.

Comments and materials received, as well as supporting documentation used in the preparation of candidate status review, will be available for public inspection, by appointment, during normal business hours at the New Mexico Ecological Services Field Office, at the street address above (telephone: (505) 346-2525).

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Wally “J” Murphy, Field Supervisor, New Mexico Ecological Services Field Office (see ADDRESSES) (telephone: (505) 346-2525; facsimile: (505) 346-2542). Persons who use a telecommunications device for the deaf (TDD) may call the Federal Information Relay Service (FIRS) at 800/877-8339.

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On February 25, 1998, we received a petition from the Southwest Center for Biological Diversity requesting that the Service add the Rio Grande cutthroat trout (Onchorynchus clarki virginalis) to the List of Endangered and Threatened Wildlife. The petition addressed the range-wide distribution of the Rio Grande cutthroat trout, including populations in Colorado and New Mexico.

Section 4(b)(3)(B) 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. We subsequently published a notice of a 90-day finding in the Federal Register (63 FR 49062, September 14, 1998). In the 90-day finding, we concluded that the petition did not present substantial information indicating that listing of the Rio Grande cutthroat trout may be warranted.

On June 9, 1999, the Southwest Center for Biological Diversity filed a complaint challenging the September 14, 1998, 90-day petition finding as violating the Act and the Administrative Procedure Act (5 U.S.C. 551 et seq). On November 8, 2001, a settlement agreement executed by both parties (the Service and the Southwest Center for Biological Diversity) was filed with the court. The settlement agreement stipulated that we would conduct a candidate status review for the Rio Grande cutthroat trout.

After completing the candidate status review for the Rio Grande cutthroat trout, the Service made a determination that listing of the trout was not warranted because the trout was neither endangered nor likely to become endangered within the foreseeable future throughout all or a significant portion of its range. Notice of that determination was published in the Federal Register on June 11, 2002 (67 FR 39936). Since that time, the Service has further defined how it analyzes what constitutes a “significant portion” of a species” range. For example, in the recent finding regarding the status of the Western Great Lakes distinct population segment of gray wolf (72 FR 6052, February 8, 2007), the Service outlined a framework for analyzing whether a species is in danger of extinction throughout a significant portion of its range. In addition, in the 5 years since the June 2002 deterimation, a significant amount of new information and data Start Printed Page 28665relevant to the Rio Grande cutthroat trout's status has been collected, such that a new candidate status review is prudent.

In light of these developments, the Service has withdrawn the June 11, 2002, candidate status review and the determination based upon that status review. The Service is initiating a new candidate status review for the Rio Grande cutthroat trout that is consistent with the new framework for analyzing “significant portion of its range” and that incorporates new information.

Request for Information

Our determination of candidate status for the Rio Grande cutthroat trout will be based upon the best available scientific and commercial data, as required under section 4(b)(1)(A) of the Act. We request that you submit any information on the Rio Grande cutthroat trout not previously submitted for our review. We are particularly interested in any relevant information gathered since June 2002 concerning the following:

(1) Current population status (e.g., population estimates, age-structure, trend) for any of the populations of the Rio Grande cutthroat trout, including methodology used for population estimation and confidence intervals if available;

(2) Rio Grande cutthroat trout's susceptibility to whirling disease, and distribution of Rio Grande cutthroat trout infected by whirling disease in New Mexico and Colorado;

(3) Distribution of Tubifix tubifix worms in the streams of New Mexico and Colorado and the susceptibility of these worms to infection;

(4) Genetic classification of any Rio Grande cutthroat trout population(s);

(5) Condition of occupied habitat;

(6) Restoration projects that have been completed, including translocation, new barrier construction or barrier repair, habitat improvement projects, or nonnative trout removal projects;

(7) Results of barrier surveys;

(8) Distribution of nonnative trout or their population size and structure in streams currently occupied by Rio Grande cutthroat trout;

(9) Status of any of the thirteen “core” populations identified in the 2002 status review (see 67 FR 39936);

(10) Current and future threats to Rio Grande cutthroat trout populations and remaining habitat areas; and

(11) Other regulatory mechanisms that address those threats, and the success of those mechanisms to date.

(12) Whether any portion of the range of the species is a significant portion of the range, and whether there are threats in that portion sufficient to meet the standards for listing under the Act.

Our candidate status review will take into consideration all comments and any additional information received, including all previous comments and information submitted during the previous candidate status review. As such, information provided during the previous status review does not need to be resubmitted.

If you are submitting e-mail comments, please include “Attn: Rio Grande cutthroat trout” in your e-mail subject header. If you do not receive a confirmation from the system that we have received your e-mail, contact us directly by calling our New Mexico Ecological Services Field Office at (505) 346-2525. Please note that comments must be received by the date specified in the DATES section in order to be considered and that the e-mail address ( will be unavailable at the termination of the public comment period.

Before including your address, phone number, e-mail address, or other personal identifying information in your comment, you should be aware that your entire comment—including your personal identifying information—;may be made publicly available at any time. While you can ask us to withhold your personal identifying information from public review, we cannot guarantee that we will be able to do so.


The primary author of this notice is the staff of the New Mexico Ecological Services Field Office.


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

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Dated: May 11, 2007.

Kenneth Stansell,

Acting Director, U.S. Fish and Wildlife Service.

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[FR Doc. E7-9590 Filed 5-21-07; 8:45 am]