Coelacanth


Description and biology

Biologists (people who study living organisms) call the coelacanth (pronounced SEE–la–kanth) a “living fossil.” This fish is the only living member of an order that was abundant 80,000,000 to 370,000,000 years ago.

A stocky fish, it is brown to steel–blue in color. It has large, rough scales and muscular lobes at the base of its fins. The coelacanth grows to a length of 5 feet (1.5 meters) and can weigh up to 150 pounds (68 kilograms). It feeds on lantern fish, cuttlefish, and other reef fish.

Like its relatives the lungfishes, the coelacanth can sense an electric field through an electroreceptive organ in its snout. When it encounters an electric field, it assumes an unusual “headstanding” position: it tilts so its head points downward and its tail points upward. Biologists believe this might be a technique the fish uses to detect prey hiding in the seabed.

A female coelacanth does not lay eggs, but gives birth to fully formed young after a gestation (pregnancy) period of over 12 months. Between 5 and 26 offspring are born at a time, each measuring about 15 inches (38 centimeters) long at birth. Young coelacanths probably live in caves and hunt at night. The fish reach sexual maturity at about 12 to 15 years of age and may live up to 80 years.

Habitat and current distribution

Coelacanths have been found in the waters off the coasts of South Africa, Mozambique, and Comoros (group of islands between northeastern Mozambique and northwestern Madagascar). The greatest concentration of these fishes seems to be around Comoros, especially near the western coast of Great Comoro Island.

Biologists have found it difficult to determine the exact number of coelacanths currently in existence. They estimate the total population to be between 200 and 300. Coelacanths inhabit caves and steep, rocky drop–offs at depths between 400 and 1,000 feet (122 and 305 meters).

Some of these fishes have been recorded at depths of almost 2,300 feet (700 meters). They congregate in caves during the day and emerge at night to hunt for food. A single coelacanth may cover a stretch of coastline over 5 miles (8 kilometers) in length in one night.

History and conservation measures

In 1938, an unusual fish was caught by fishermen off the eastern coast of South Africa. British amateur ichthyologist (scientist who studies fishes) James L. B. Smith identified it as a coelacanth.

Scientists had previously thought this fish had been extinct for 80,000,000 years. In 1952, biologists found coelacanths living and breeding off Comoros. It was then discovered that native inhabitants of the islands had been catching and eating the fish for years.

Word of these discoveries soon spread. Museums, aquariums, and private collectors quickly sought the elusive fish, paying high prices. The number of coelacanths caught increased each year, reaching a high of 11 in 1986.

In 1989, the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES; an international treaty to protect wildlife) granted the fish Appendix I status. This banned the trade of the fish between nations that had signed the treaty.

In recent years, coelacanths have been caught and then sold illegally in eastern Asia. People in the region believe fluid from a certain part of the fish’s body promotes longer life in humans.

The Coelacanth Conservation Council, established in 1987 in Moroni, Great Comoro Island, promotes public education programs coordinates research, and organizes protection efforts for the endangered coelacanth.

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