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Suit Filed To Protect Endangered Species at Bitter Lake Refuge

December 19, 2007
Nicole Rosmarino, Ph.D., Conservation Director, WildEarth Guardians, 505-988-9126x1156, nrosmarino@fguardians.org
In This Release
Wildlife   Koster’s springsnail, Noel’s amphipod, Pecos assiminea
Santa Fe, NM-WildEarth Guardians and the Center for Biological Diversity filed suit today against the U.S. Fish and Wildlife Service for refusing to designate and protect critical habitat for four endangered species that inhabit the Bitter Lake National Wildlife Refuge. Earthjustice filed the suit on behalf of the groups in federal court.

The Roswell springsnail, Koster’s springsnail, and Noel’s amphipod (a freshwater shrimp) are found nowhere else but the Bitter Lake Refuge, located northeast of Roswell, New Mexico. The Pecos assiminea snail is found on the refuge and also in limited areas in Texas. In 2002, Fish and Wildlife Service scientists proposed to designate 1,523 acres of critical habitat for the Pecos assiminea snail and 1,127 acres for each of the other three species. When the decision was finalized in 2005, the agency slashed the Pecos assiminea snail habitat 74 percent to just 397 acres in Texas. All of the habitat was slashed for the other three species.

The Fish and Wildlife Service achieved this massive reduction by eliminating all critical habitat on the Bitter Lake Refuge under the false claim that it is sufficiently protected already.

“Critical habitat for these endangered animals is vital for their survival and would have the added benefit of protecting Bitter Lake from oil and gas,” said Dr. Nicole Rosmarino of WildEarth Guardians. “Bitter Lake is a biological gem, but it is at extreme risk from the frenzy of oil and gas development occurring on New Mexico’s public lands.”

“The federal government has already recognized these species are on the brink of extinction. They cannot at the same time argue that they are adequately protected. Not only is this reasoning illogical, it is also illegal,” said Robin Cooley, attorney for Earthjustice.

Water contamination is the primary concern with oil and gas drilling in and adjacent to the Bitter Lake Refuge. The concern is real: in May 1994, Yates Petroleum caused a spill of brine onto the refuge. The water had a chloride content 20 times higher than the state contamination standard. Refuge staff described the spill as a “tragedy” given potential dangers to the refuge’s springs, ponds, associated wetlands, underground water sources, and endangered wildlife.

The Fish and Wildlife Service recognizes that endangered invertebrates are extremely sensitive to water contamination and their very narrow ranges make them vulnerable to extinction. Just “one contamination event…could result in the loss of an entire population, of which there are few,” wrote the Service when it listed the species under the Endangered Species Act in August 2005. Given their sensitivity, the snails are “indicators” of water quality for the Roswell Basin.

“Scientific research shows that species with critical habitat recover twice as fast as species without habitat protection,” said Kieran Suckling, policy director of the Center for Biological Diversity. “These species simply aren’t going to survive unless we protect the places where they live.”

WildEarth Guardians and the Center for Biological Diversity contend that, while the refuge is managed for wildlife, refuge managers do not manage the minerals underneath Bitter Lake. Key subsurface areas have been leased out by the state and the Bureau of Land Management and some are privately owned. As a result, there are at least seven oil and gas wells operating on the refuge – all of which pose dangers from contamination.

Last year, Yates Petroleum Company filed applications for two more gas wells on the Refuge, one of which was located just one-quarter mile from the visitor’s center and only 200-300 yards upstream of habitat occupied by the endangered invertebrates. After pressure from the state Department of Game and Fish, the Bitter Lake Refuge, and WildEarth Guardians, Yates withdrew its applications. The company could reapply at any time.

In addition to dangers on the refuge itself, the highly sensitive snails and shrimp face risks to their water quality from oil and gas operations in the area west of the refuge, which is the source of Bitter Lake’s water. The BLM approved a plan in October 2006 that would allow up to 91 additional oil and gas wells to be drilled in this source water area. While the agency instituted drilling requirements to reduce the risk of contamination, it acknowledged that some risk remained to the refuge’s water and the endangered invertebrates. Drilling under that plan could occur at any time.


Bitter Lake Refuge contains unique features including sinkholes, playa lakes, seeps, and gypsum springs fed by an underground river, and it provides habitat to rare invertebrates and plants as well as 485 wildlife species. Additional endangered species that live here are the Pecos sunflower, Pecos gambusia, Pecos bluntnose shiner, and least tern. The refuge hosts a “Dragonfly Festival” every year, given the 90 species of dragonflies and damselflies that occur at Bitter Lake.

Critical habitat designation for these endangered invertebrates would provide additional safeguards for the species from federal actions that authorize harmful activities, including the expansion of oil and gas drilling on public lands in southeastern New Mexico. Such drilling and associated industrial operations can deplete groundwater supplies and pollute both ground and surface water with oil and other contaminants, which would doom these rare animals. Some have already disappeared from other springs that have dried up or are contaminated. The snails and crustacean are so small they are barely visible through the naked eye. But they are indicators of the purity of the ground water that they depend on and that they have evolved to live in over tens of thousands of years.

Descriptions of the species

The Roswell springsnail (Pyrgulopsis roswellensis) is 3 to 3.5 mm long with a narrowly conical shell that is tan in color and can have up to five whorls or twists. In the past the snail lived in various springs in the vicinity of Roswell, New Mexico. However, several of these habitats have completely dried up due to groundwater pumping, eliminating these populations. Currently, the only known populations of the Roswell springsnail live within three discrete areas of Bitter Lake National Wildlife Refuge in Chaves County, New Mexico.

Koster’s springsnail (Juturnia kosteri) is 4 to 4.5 mm long, with a narrowly conical tan colored shell with 4? to 5? whorls. Although it was historically found within the Bitter Lake NWR and other springs in the Roswell area, much of its habitat has dried up due to groundwater pumping, leaving only two known populations, both within the refuge.

Pecos assiminea (Assiminea pecosensis) is the smallest of the snails, 1.55 to 1.87 mm in length. It has a regularly conical shell that is chestnut-brown and nearly transparent with as many as 4? whorls. Pecos assiminea prefers habitats where it is not completely immersed in water, such as wet mud or beneath vegetation mats, typically within a few centimeters of running water. Historically, this species occurred in Texas, New Mexico, and Mexico, but now it only survives at two sites within the Bitter Lake NWR and in two properties managed by the Nature Conservancy in Pecos and Reeves County, Texas.

Noel’s amphipod (Gammarus desperatus) is a freshwater crustacean ranging in size from 8.5 to 14.8 mm long with the males slightly larger than females. This freshwater shrimp is brownish green with kidney-shaped eyes and red bands along its body. It is very sensitive to light and thus dwells at the bottom of water courses, where it is darker. As its scientific name (desperatus) suggests, it is in dire peril. Historically found within the Bitter Lake NWR and other springs in the Roswell area, it has been extirpated outside the refuge and its habitat on the refuge was severely damaged by a 2002 fire. That fire reduced the population to just four organisms, due to deposits of ash and sediment and loss of vegetative cover which previously sheltered them from light.

Other Contact
Kieran Suckling, Policy Director, Center for Biological Diversity, 520-275-5960, ksuckling@biologicaldiversity.org, Robin Cooley, Attorney, Earthjustice, 303-623-9466x611, rcooley@earthjustice.org