Pacific Southwest Region
California, Nevada and Klamath Basin

Economic Analysis for San Diego Ambrosia Critical Habitat Proposal Available for Public Review and Comment

May 18, 2010

May 18, 2010 
Contact: Jane Hendron: 760-431-9440 ext. 205


Economic Analysis for San Diego Ambrosia Critical Habitat Proposal
Available for Public Review and Comment
Fish and Wildlife Service also announces several revisions to proposed critical habitat 

Carlsbad, CA -- The U.S. Fish and Wildlife Service (Service) announced today the availability of a draft economic analysis for its August 27, 2009, proposed rule to designate critical habitat for San Diego ambrosia (ambrosia pumila), a federally-listed endangered plant found in portions of Riverside and San Diego counties. 

Based on comments and information received after publication of the August 2009, proposed rule, we identified additional subunit 3B (Murrieta Creek), subunit 4D (Gird Road/Monserate Hill), and subunit 5B (Crosby Estates) as essential to the conservation of San Diego ambrosia and are including them as proposed critical habitat. However, both subunits 3B and 5B fall within the boundaries regional habitat conservation plans; therefore, we are considering excluding them from the final designation of critical habitat. 

The draft analysis estimates incremental economic costs associated with areas proposed for critical habitat designation to be $118,750 over the next 20 years ($11,203 annualized using a 7 percent discount rate).

These incremental costs do not include the addition of subunits 3B, 4D, and 5B as proposed critical habitat but potential economic impacts for these areas is anticipated to be minor. 

San Diego ambrosia has a branching root structure that spreads horizontally underground sprouting new stems each year. These stems generally grow 2 to 12 inches high and produce yellowish to greenish-colored flowers from May to October. The plant produces very few seeds, diminishing its ability to spread and colonize unoccupied areas. 

The August 27, 2009 proposed rule include 802 acres of proposed critical habitat. The addition of subunits 3B, 4D, and 5B (totaling 338 acres) increase the proposed designation to 1,140 acres. 

Comments and information on the draft economic analysis and the proposed rule will be accepted until June 17, 2010. 

You may submit comments electronically to: Comments may be submitted by U.S. mail or hand-delivered to: Public Comments Processing, Attn: FWS–R8–ES–2009–0054; Division of Policy and Directives Management; U.S. Fish and Wildlife Service; 4401 N. Fairfax Drive, Suite 222; Arlington, VA 22203.  

Copies of the proposed critical habitat rule, draft economic analysis, and public comments received are available on the Internet at  

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