Ozark Cavefish (Amblyopsis rosae)

Status: Threatened (49 FR 43965; November 1, 1984). Critical habitat has not been designated.

Description: The Ozark cavefish is pinkish-white and reaches a maximum length of two inches (5 cm). The head is flattened, and it has a slightly protruding lower jaw. The fish has no pelvic fin; the dorsal and anal fins are farther back than on most fish. The Ozark cavefish has only rudimentary eyes and no optic nerve.

Life History: The Ozark cavefish lives only in caves. It has no pigmentation and a loss of unused characters. However, it is well-adapted to a cave environment through well-developed sensory papillae. They feed primarily on microscopic organisms, as well as small crustaceans and salamander larvae. The reproductive rate of Ozark cavefish is relatively low compared to most other fish.

Habitat: Caves which have populations of the Ozark cavefish all have a relatively large source of nutrients, such as bat guano or blown leaf litter. Water quality in caves that contain cavefish is usually high. Ozark cavefish are able to tolerate the extremely low oxygen content of ground water found in caves. Cavefish tend to occur in flowing cave streams as opposed to quiet pools.

Distribution: The Ozark cavefish is native to the Springfield Plateau of the Ozark Highlands (southwestern Missouri, northwestern Arkansas, and northeastern Oklahoma). Currently, 15 caves in this area have verified cavefish populations. In Oklahoma, populations are known to occur in Delaware County. There are historical records for Ottawa and Mayes counties.

Causes of Decline: Factors that have led to the decline of the Ozark cavefish include destruction of habitat, collecting of specimens, and disturbance by spelunkers.

Recovery Needs: Protection of caves containing cavefish is the most important task. This includes monitoring the quality of water that flows into caves, and erecting fences or gates that limit access by humans, but that do not interfere with bat populations.

Other information: The states of Arkansas, Missouri, and Oklahoma have each purchased a cave to protect the cavefish. In many caves, the major source of energy for the organisms on which cavefish feed is bat guano. Therefore, Ozark cavefish survival is dependent on the survival of bats, such as the endangered gray bat (Myotis grisescens).

Funds are currently available through the Healthy Forest Reserve Program (HFRP) in northeastern Oklahoma to protect and enhance forested wildlife habitat for threatened and endangered species and other declining wildlife populations. The federally listed species for habitat and population recovery activities include the gray bat, the Ozark big-eared bat, and the Ozark cavefish. The HFRP is administered by the Natural Resources Conservation Service (NRCS). The HFRP in Oklahoma is being implemented in coordination between NRCS, the U.S. Fish & Wildlife Service (USFWS), and Oklahoma Forestry Services (OFS).