Two Hawaiian Cave Animals Added
to Endangered Species List

The U.S. Fish and Wildlife Service today listed two small, blind Hawaiian cave animals — the Kauai cave wolf spider and Kauai cave amphipod — as endangered under the Endangered Species Act.The two species exist in a predator-prey relationship in the inky blackness of moist lava tubes and adjacent crevices in the Koloa lava flows in southeastern Kauai.

Species are designated as endangered under the Endangered Species Act when they are in danger of becoming extinct through all or a significant portion of their range. The two species are found in only a handful of caves on the island.

The Kauai cave wolf spider is a small sightless hunting spider adapted to life in the lava tubes. Instead of building webs, it chases and grabs its prey. Unlike most wolf spiders, the Kauai cave wolf spider produces only 15 to 30 eggs per clutch. Newly hatched spiderlings are unusually large and are carried on the back of the female for only a few days. Only three populations of the Kauai cave wolf spider are known to exist.

The Kauai cave amphipod is a small, pale landhopper that resembles a shrimp. Like the cave wolf

spider, the Kauai cave amphipod has no eyes. It feeds on the decaying roots of surface vegetation that reach into the cave system, as well as rotting sticks, branches, and other plant materials. This amphipod, which is believed to be the primary prey of the Kauai cave wolf spider, is known from only five populations.

"Both of these Kauai cave species are fascinating examples of adaptation to their habitat," said Anne Badgley, the Service’s regional director for the Pacific Region. "Both were discovered in 1971 in subterranean areas not originally expected to provide habitat for any cave animals. By working withothers, including private landowners, we hope to ensure their continued survival."

The two animals are threatened by the deterioration of their cave habitat caused by clearing, grading, filling, paving, and other activities associated with development and agriculture. They also are susceptible to the use of chemical and biological pest controls, which often are employed to control nonnative insects such as ants and cockroaches.

Under the Endangered Species Act, a recovery plan identifying steps to be taken to overcome these threats will be developed and implemented. Recovery strategies for these cave species will include working with landowners to protect remaining cave habitats by sealing cave entrances and planting native and other perennial vegetation on surface areas above the caves to restore a root system to the cave ecosystem. Restrictions on pesticide use around the caves and on the release of certain biocontrol agents may be required.

The Kauai cave wolf spider and amphipod are found only on private lands. The U.S. Fish and Wildlife Service has been working with the Kukui‘ula Development Corporation since 1995 to help restore and protect two caves on the company’s property that provide habitat for the Kauai cave wolf spider and the Kauai cave amphipod. The company has agreed to set aside the land area above these two caves as either a limited use park or reserve to further protect these species. The Service hopes to undertake similar partnerships with other private landowners.

A proposal to list these species as endangered was published in the Federal Register on December 5, 1997. The final rule was published in today’s Federal Register.

The U.S. Fish and Wildlife Service is the principal Federal agency responsible for conserving, protecting, and enhancing fish, wildlife and plants and their habitats for the continuing benefit of the American people. The Service manages the 93-million-acre National Wildlife Refuge System comprised of more than 500 national wildlife refuges, thousands of small wetlands, and other special management areas. It also operates 66 national fish hatcheries, 64 fish and wildlife management assistance offices and 78 ecological services field

stations. The agency enforces Federal wildlife laws, administers the Endangered Species Act, manages migratory bird populations, restores nationally significant fisheries, conserves and restores wildlife habitat such as wetlands, and helps foreign governments with their conservation efforts. It also oversees the Federal Aid program that distributes hundreds of millions of dollars in excise taxes on fishing and hunting equipment to state fish and wildlife agencies.

— FWS —