|July 27, 2005
A draft recovery plan outlining the recovery strategies for the
Kauai cave wolf spider and Kauai cave amphipod was released for
public comment today by the U.S. Fish and Wildlife Service. The two
species are known to exist only in the lava tubes and cave-bearing
rock in Kauai's Koloa Basin.
"This plan will lead the cooperative efforts of the Service, the
State of Hawaii, and many other partners as they work to recover
these two rare species," said Dave Allen, Pacific regional director
for the Fish and Wildlife Service. "With the known population of the
Kauai cave spider - perhaps fewer than 30 individuals - all in a
single cave, we need to take action quickly to ensure that the only
eyeless wolf spider in the world continues to survive."
Six broad recovery tasks are discussed in the draft plan: protecting
known cave systems where the Kauai cave wolf spider and amphipod
exist; enhancing currently and recently occupied habitats;
conducting research to gain additional knowledge of the species and
their conservation needs; enhancing public knowledge of and support
for protecting these species; validating recovery objectives; and
developing a post-delisting monitoring plan.
The first priorities identified in the plan are to protect the cave
systems where these species still exist from human-caused
destruction or degradation and to enhance their existing habitat.
The cave amphipod is regularly found in three caves, including one
where the cave wolf spider is found.
To protect the cave systems, the draft recovery plan recommends
controlling human entry, preventing the destruction of native plant
communities above the cave systems, developing and implementing a
fire control plan for surface habitats, preventing introduction of
and controlling currently present nonnative predators and
competitors, preventing the introduction of bio-control organisms or
bio-pesticides, and preventing contamination by pollutants such as
insecticides and herbicides.
To enhance their habitats, the draft plan recommends managing the
habitat above the caves to encourage the growth of appropriate
plants whose roots provide food and debris for the cave amphipod,
and to increase the relative humidity in caves. These cave-swelling
species (known as troglobites) appear to require high humidity,
perhaps as much as 100% humidity.
These two species were first discovered in 1971 and much about their
conservation needs remains unknown. Research recommended within the
draft plan includes studies:
● to determine local populations sizes
● to determine the most beneficial
plants to be used for habitat improvement;
● to develop noninvasive ways to
determine the status of populations;
● to learn more about regulating the
humidity of caves and its effect on these species and nonnative
● to look for additional occupied caves
or restorable cave systems;
● to continue monitoring activities; and
● to determine the feasibility of moving
wolf spiders into unoccupied cave systems.
Public education activities are encouraged to broaden knowledge of
the Kauai cave species in the Koloa and Poipu area, and to engender
public support for these unique creatures. Providing technical
expertise and/or funding to implement land uses friendly to these
species also is encouraged.
The Kauai cave wolf spider is a mid-size (0.50 to 0.75-inch) hunting
spider that has completely lost its eyes as part of its adaptation
to life in lava tubes. Instead of building webs, it chases and grabs
its prey or may use sit-and wait ambush tactics. Unlike most wolf
spiders that produce 100 to 300 spiderlings per clutch, the Kauai
cave wolf spider is believed to produce fewer than 30 spiderlings
per clutch. Newly hatched spiderlings are unusually large and are
carried on the back of the female for only a few days.
The Kauai cave amphipod is a small (0.25 to 0.4-inch) pale
landhopper that resembles a shrimp. Like the cave wolf spider, the
Kauai cave amphipod has lost its 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 is believed to be a food source for the Kauai cave wolf
The Kauai cave wolf spider and cave amphipod were listed as
endangered on January 14, 2000. On June 2, 2000, the U.S. District
Court ordered the Fish and Wildlife Service to designate critical
habitat for these species. Critical habitat for the species was
designated on April 9, 2003, in the Federal Register.
The availability of the draft recovery plan for a 60-day public
comment period was announced in the Federal Register on February 9.
Copies of the draft recovery plan are available through the Fish and
Wildlife Service=s website at http://pacificislands.fws.gov or by
calling the Fish and Wildlife Service=s Honolulu office at 808 792
9400. Written comments may be submitted to the Field Supervisor,
Pacific Islands Fish and Wildlife Office, 300 Ala Moana Blvd., Room
3-122, Box 50088, Honolulu, HI 96850.