Protecting endangered species and wild places through
science, policy, education, and environmental law.

NEWS RELEASE – for immediate release May 16, 2005


Proposed highway project and sprawl development remain major threats to desert web-of-life in Washington County.

Contact: Tony Frates, Rare Plant Coordinator, UNPS 801.277.9240
Daniel R. Patterson, Desert Ecologist, Center 520.623.5252 x306
Dr. Emily Roberson, Botanist, Native Plant Conservation Campaign 415.970.0394

WASHINGTON DC – The US Interior Dept., Center for Biological Diversity (Center), and Utah Native Plant Society (UNPS) have agreed to settle a lawsuit filed Sept. 27 against the US Fish & Wildlife Service (FWS) seeking critical habitat for two endangered Mojave Desert plants found only near St. George UT, the Holmgren milkvetch and the Shivwits milkvetch, as required by the Endangered Species Act (ESA).

FWS has agreed to publish a critical habitat proposal by March 17, 2006, and finalize it by December 16, 2006. This conservation victory is a part of the Center's Native Plant Conservation Campaign.

“Critical habitat works – it’s the most important action to recover endangered species,” said Daniel R. Patterson, Desert Ecologist with the Center. “As wildlife habitat in the Mojave Desert is lost, so is the human quality of life. We offer to work closely with FWS to get a proposal done quickly to secure habitat for conservation and recovery, too bad it took a lawsuit to get FWS to move.”

Initially discovered in 1941 but not rediscovered again until 1979, the rare Holmgren milkvetch (Astragalus holmgreniorum, named in honor of Drs. Noel and Patricia Holmgren and also known as Paradox milkvetch), and the Shivwits milkvetch (Astragalus ampullarioides, also known as Shem milkvetch, in reference to a site where the species was first found in 1976) were both listed as endangered species by FWS on 9/28/01, under an agreement with the Center. Both species occur only in Washington County near sprawling St. George, Utah (except for a small area just over the state line in Mohave County AZ historically occupied by the Holmgren milkvetch, but the plant may now be extirpated there).

There are only three known populations of Holmgren milkvetch. The primary population lives within a limited area south of St. George along the Utah-Arizona border. This population is seriously threatened by a proposed interchange that would connect I-15 to the proposed Southern Corridor highway, as well as urban sprawl planned by the state of Utah, and other habitat loss that would follow the highway. The highway plan is currently out for public comment through June 22.

The Shivwits milkvetch lives on only five known sites. Most habitat at one site that formerly harbored several hundred plants was nearly destroyed by a recent golf course development. Both species are also threatened by non-native invasive plant species, off-road vehicles, mining, and livestock grazing.

Habitat destruction is the primary threat to both of these endemic species. “These species are truly in peril”, said Dr. Renee Van Buren, a Botanist with Utah Valley State College who specializes in endangered species. “Critical habitat protection is essential to prevent their extinction, and promote recovery.”

A primary purpose of the ESA is to provide a mechanism so that “…the ecosystems upon which endangered species and threatened species depend may be conserved…” These species are severely restricted geographically, just as if they were living on islands. Typically rare plant species have adapted to specific soil types and microenvironments outside of which they cannot survive. This includes a complex association with other species, including ground nesting, solitary native bees (rare plants usually do not self-pollinate). Therefore, it is essential to protect the habitat in which these plants thrive in order to ensure the continued existence of these species.

Peer-reviewed and published studies by the Center using FWS’ own data proves that endangered plants & animals with critical habitat are less likely to be declining, and twice as likely to be recovering, than those without. Yet, FWS has designated critical habitat for only 37% of endangered wildlife in Utah.

While not the case for most of Utah’s 24 federally listed plant species, FWS found that designating critical habitat for the Holmgren milkvetch and the Shivwits milkvetch would be prudent and beneficial to the species. Yet 3 years after listing, FWS still has not designated critical habitat or finished recovery plans for the two species as required by U.S. law. Private landowners are not affected by the federal listing of plant species, nor the designation of critical habitat.

Utah has over 2700 species of native plants and it is estimated that over 10% of these are globally rare and potentially vulnerable. The extent to which a species is considered rare involves a variety of factors including the number of populations and remaining individual plants, and the area over which it occurs.

Plaintiffs were represented by attorney Robin Cooley of the Center’s Environmental Law Clinical Partnership at the University of Denver College of Law. Contact Daniel Patterson for a copy of the critical habitat agreement.

More on the conservation and recovery benefits of critical habitat:

Native Plant Conservation Campaign:

Holmgren milkvetch, a Mojave Desert member of the Pea Family, has attractive white-tipped purple flowers.

Holmgren milkvetch plants only live for 2-3 years and need specialized habitat.

Shivwits milkvetch, also a member of the Pea Family, has nice yellow flowers.

Shivwits milkvetch has a longer lifespan, but can only live on the purple clay soils of the Chinle formation.

Photos by Tony Frates, UNPS


more press releases. . .

Go back