Skip to Content

Proposed Rule

Endangered and Threatened Wildlife and Plants; Threatened Species Status for the Headwater Chub and a Distinct Population Segment of the Roundtail Chub

Document Details

Information about this document as published in the Federal Register.

Enhanced Content

Relevant information about this document from provides additional context. This information is not part of the official Federal Register document.

Published Document

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

Start Preamble


Fish and Wildlife Service, Interior.


Proposed rule; reopening of the comment period.


We, the U.S. Fish and Wildlife Service (Service), announce the comment period reopening on our proposed rules to add the headwater chub (Gila nigra) and the roundtail chub (Gila robusta) distinct population segment (DPS) as threatened species to the List of Endangered and Threatened Wildlife. We are taking this action based on significant new information regarding the species' taxonomic status as presented by the American Fisheries Society and the American Society of Ichthyologists and Herpetologists (AFS/ASIH) Joint Committee on the Names of Fishes. We are reopening the comment period for 45 days to provide the public additional time to review and consider our proposed rulemakings in light of this new information.


The comment period end date for the proposed rule that published at 80 FR 60754 on October 7, 2015, is December 16, 2016. We request that comments be submitted by 11:59 p.m. Eastern Time on the closing date.


Comment submission: You may submit comments by one of the following methods:

(1) Electronically: Go to the Federal eRulemaking Portal: In the Search box, enter the appropriate Docket No.: FWS- R2-ES-2015-0148 for the proposed threatened status for headwater chub and the roundtail chub distinct population segment. You may submit a comment by clicking on “Comment Now!”

(2) By hard copy: Submit by U.S. mail or hand-delivery to: Public Comments Processing, Attn: FWS-R2-ES-2015-0148; U.S. Fish and Wildlife Service Headquarters, MS: BPHC, 5275 Leesburg Pike, Falls Church, VA 22041-3803.

We request that you send comments only by the methods described above. We will post all comments on This generally means that we will post any personal information you provide us (see the Public Comments section below for more information). Comments previously submitted need not be resubmitted as they are already incorporated into the public record and will be fully considered in the final determinations.

Document availability: The new scientific information described in this document is available at in Docket No. FWS-R2-ES-2015-0148.

Start Further Info


Steve Spangle, Field Supervisor, U.S. Fish and Wildlife Service, Arizona Ecological Services Field Office; telephone 602-242-0210; facsimile 602-242-2513. Persons who use a telecommunications device for the deaf (TDD) may call the Federal Information Relay Service (FIRS) at (800-877-8339).

End Further Info End Preamble Start Supplemental Information Start Printed Page 75802


Previous Federal Actions

On October 7, 2015 (80 FR 60754), we published a proposed rule that the headwater chub and the lower Colorado River basin roundtail chub DPS are threatened species under the Endangered Species Act of 1973, as amended (Act) (16 U.S.C. 1531 et seq.). Section 4(b)(6)(A) of the Act requires that we make final listing determinations within 1 year of the proposed rule, except where, as in this instance, there is substantial disagreement regarding the sufficiency or accuracy of the available data, which allows for an additional 6 months. On August 15, 2016 (81 FR 54018), we announced a 6-month extension on the proposed rule's final determination due to substantial disagreement regarding the available data's sufficiency or accuracy, and reopened the comment period for 30 days. Accordingly, the deadline to finalize or withdraw the proposed rule is April 7, 2017. For a description of additional previous Federal actions concerning these species, please refer to the proposed listing rule (October 7, 2015; 80 FR 60754).


In the proposed rule (October 7, 2015; 80 FR 60754), we evaluated headwater and roundtail chubs as separate species. However, commenters raised questions regarding the headwater and roundtail chubs' taxonomic distinctness, as related to one another and to the Gila chub (Gila intermedia). The Gila chub is listed as an endangered species (November 2, 2005; 70 FR 66664). Some scientists knowledgeable about the species contend that the three entities are not separate species.

For this reason, the Arizona Game and Fish Department requested that the AFS/ASIH evaluate the most recent literature associated with roundtail chub, headwater chub, and Gila chub taxonomy. The AFS/ASIH is recognized as the authority in establishing the taxonomic status of fish. The panel met in April 2016 and again in August 2016, and presented their conclusions in a final report to the Arizona Game and Fish Department on September 1, 2016 (Page et al. 2016; see Docket No. FWS-R2-ES-2015-0148 at The AFS/ASIH review (Page et al. 2016) included published and unpublished studies and reports presented to them in April 2016, and a more recent, unpublished report by Copus et al. (2016), which was included as an appendix to Page et al. (2016). Based on the information reviewed, the AFS/ASIH panel concluded that “no morphological or genetic data define populations of Gila in the lower Colorado River basin (which includes the Little Colorado River, Bill Williams River, Gila River, Verde River, and Salt River drainages) as members of more than one species” and “that the data available support recognition of only one species of Gila, the roundtail chub, Gila robusta” (Page et al. 2016). This new information could be of significant consequence in our final listing determination because our proposed rule reviewed these entities as separate species. Given the new information, we must now review the proposed entities' validity as recognized species. Further, this information was not previously included or considered in our proposed rulemaking or made available to the public. Therefore, we are reopening the comment period for 45 days to allow consideration of this new information, as well as any other aspect of the proposed rule, prior to finalizing our decision.

Public Comments

We will accept written comments and information during this reopened comment period on our proposed headwater chub and roundtail chub DPS listing published in the Federal Register on October 7, 2015 (80 FR 60754). We will consider information and recommendations from all interested parties. We intend that any final action resulting from these proposals be as accurate as possible and based on the best available scientific and commercial data.

In considering the new information received from the AFS/ASIH, as well as the information provided in the proposed rule, we are particularly seeking comments considering:

(a) Roundtail, headwater, and Gila chub genetics and taxonomy;

(b) Roundtail, headwater, and Gila chubs' morphological characteristics;

(c) Those topics previously noted in the October 7, 2015, proposed rule (see 80 FR 60754).

If you previously submitted comments or information on the proposed rule, please do not resubmit them. We have incorporated them into the public record, and we will fully consider them in preparing our final determinations. Our final determinations will take into consideration all written comments and any additional information we received.

You may submit your comments and materials concerning this proposed rule by one of the methods listed above in ADDRESSES. We request that you send comments only by the methods described in ADDRESSES.

If you submit information via, your entire submission—including any personal identifying information—will be posted on the Web site. If your submission is made via a hardcopy that includes personal identifying information, you may request at the top of your document that we withhold this information from public review. However, we cannot guarantee that we will be able to do so. We will post all hardcopy submissions on

Comments and materials we receive, as well as supporting documentation we used in preparing the proposed rule, will be available for public inspection on, or by appointment, during normal business hours, at the U.S. Fish and Wildlife Service, Arizona Ecological Services Field Office (see FOR FURTHER INFORMATION CONTACT). You may obtain copies of the proposed rule on the Internet at at Docket No. FWS-R2-ES-2015-0148. Copies of the proposed rule are also available at​southwest/​es/​arizona.

References Cited

Copus, J.M., Z. Foresman, W.L. Montgomery, B.W. Bowen, and R.J. Toonen. 2016. Revision of the Gila robusta (Teleostei, Cyprinidae) species complex: Morphological examination and molecular phylogenetics reveal a single species. Report to the Joint ASIH-AFS Committee on Names of Fishes.

Page, L.M., C.C. Baldwin, H. Espinosa-Perez, C.R. Gilbert, K.E. Hartel, R.N. Lea, NE. Mandrak, J.J. Schmitter-Soto, and H.J. Walker. 2016. Final report of the AFS/ASIH Joint Committee on the Names of Fishes on the taxonomy of Gila in the Lower Colorado River basin of Arizona and New Mexico. Report to the Arizona Game and Fish Department. 4 pp.


The primary author(s) of this notice are the Arizona Ecological Services Field Office staff members.


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

Start Signature

Dated: October 20, 2016.

Stephen Guertin,

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

End Signature End Supplemental Information

[FR Doc. 2016-26125 Filed 10-31-16; 8:45 am]