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Proposed Rule

Endangered and Threatened Wildlife and Plants; Reopening of Comment Period and Notice of Availability of Draft Economic Analysis for Proposed Critical Habitat Determination for the Riverside Fairy Shrimp

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Fish and Wildlife Service, Interior.


Proposed rule; reopening of comment period and notice of availability of draft economic analysis.


The U.S. Fish and Wildlife Service (Service) announces the availability of the draft economic analysis for the proposed designation of critical habitat for the Riverside fairy shrimp (Streptocephalus woottoni). We also provide notice of the reopening of the comment period for the proposal to designate critical habitat for the Riverside fairy shrimp to allow all interested parties to submit written comments on the proposal and on the draft economic analysis. Comments previously submitted need not be resubmitted as they will be incorporated into the public record as a part of this reopened comment period and will be fully considered in the final rule.


The original comment period on the critical habitat proposal closed on November 6, 2000. The comment period is reopened and we will accept comments until March 30, 2001. Comments must be received by the closing date. Any comments that are received after the closing date may not be considered in the final decision on this proposal.


Copies of the draft economic analysis are available on the Internet at or by writing to the Field Supervisor, U.S. Fish and Wildlife Service, Carlsbad Fish and Wildlife Office, 2730 Loker Avenue West, Carlsbad, California 92008. Written comments should be sent to the Field Supervisor. You may also send comments by electronic mail (e-mail) to Please submit comments in ASCII file format and avoid the use of special characters and encryption. Please include “Attn: Riverside fairy shrimp” and your name and return address in your e-mail message. If you do not receive a confirmation from the system that we have received your e-mail message, contact us directly by calling our Carlsbad Fish and Wildlife Office at phone number 760-431-9440. Comments and materials received will be available for public inspection, by appointment, during normal business hours at the above Service address.

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Douglas Krofta, Fish and Wildlife Biologist, Carlsbad Fish and Wildlife Office, at the above address (telephone 760-431-9440; facsimile 760-431-9624).

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The Riverside fairy shrimp is a small aquatic crustacean that occurs in vernal pools, ephemeral ponds, and human-modified depressions. Basins, ponds, and depressions that support Riverside fairy shrimp are located on coastal terraces and plateaus ranging from coastal southern California to northwestern Baja California, Mexico. Typically, this species is found in vernal pools that are deeper and cooler than those basins which support the related species, the endangered San Diego fairy shrimp (Branchinecta sandiegonensis).

Basins that support Riverside fairy shrimp are typically dry a portion of the year, but usually are filled by late fall, winter, or spring rains, and may persist into April or May. Critical to the formation of vernal pool basins is the presence of nearly impermeable surface or subsurface soil layers and flat or gently sloping topography. Historically, vernal pool soils and habitats covered extensive areas on the coastal plains and mesas of Los Angeles, Orange, Riverside, San Diego, and Ventura Counties. Significant losses of vernal Start Printed Page 12755pools supporting the Riverside fairy shrimp have occurred throughout these areas due to urban and water development, flood control, highway and utility projects, as well as the conversion of wildlands to agricultural and other human uses.

The species was Federally listed as endangered throughout its range on August 3, 1993 (58 FR 41384), and its continued survival is reduced by habitat loss and degradation. On September 21, 2000, the Fish and Wildlife Service published a rule proposing critical habitat for the Riverside fairy shrimp in the Federal Register (65 FR 57136). We proposed designation of approximately 4,880 hectares (12,060 acres) as critical habitat for the Riverside fairy shrimp pursuant to the Endangered Species Act of 1973, as amended (Act). Proposed critical habitat is in Los Angeles, Orange, Riverside, San Diego, and Ventura Counties, California, as described in the proposed rule.

Section 4(b)(2) of the Act requires that the Secretary shall designate or revise critical habitat based upon the best scientific and commercial data available and after taking into consideration the economic impact of specifying any particular area as critical habitat. Based upon the previously published proposal to designate critical habitat for the Riverside fairy shrimp and comments received during previous comment period, we have prepared a draft economic analysis of the proposed critical habitat designation, which is available at the above Internet and mailing address.

Public Comment Solicited

We have reopened the comment period at this time in order to accept the best and most current scientific and commercial data available regarding the proposed critical habitat and the draft economic analysis. Previously submitted written comments on this critical habitat proposal need not be resubmitted. The current comment period on this proposal closes on March 30, 2001. Written comments may be submitted to the Service office in the ADDRESSES section.


The primary author of this notice is Douglas Krofta (see ADDRESSES section).


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

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Dated: February 20, 2001.

David Patte,

Acting Manager, California/Nevada Operations.

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[FR Doc. 01-4844 Filed 2-27-01; 8:45 am]