turtle farming

A study that may lead to green turtle farming

Green turtles, prized for their oil, meat and leather, are to be studied intensively in one of their last natural refuges, the Torres Straits Islands of northern Aus tralia.

If a three year research project at Darnley and Murray Islands is a success it will lead to the setting up of one of the world’s first green turtle farms, bringing the possibility of new prosperity to these islands of the South Pacific.

Armed with a Commonwealth grant of $27,730 to carry out the first year of his ecological investiga tion of the green turtle, Dr. Robert Bustard, Research Fellow at the Research School of Biological Sciences at the Australian National University, is to set up six farms at Darnley and Murray, employing local people as much as possible.

“I am interested in the ecology and numbers of green turtles,” Dr.

Bustard, 32, said in Canberra. “In any animal population the numbers remain fairly constant in the long term. I am interested in how animal populations stabilise their numbers.

This research has its application in that when you know how animals stabilise their numbers you can manipulate the process to multiply their numbers.”

The green turtle population appears to have remained fairly static because of their high infant mortality rate.

In a breeding year a female lays a clutch of about 110 eggs every 14 days—or 600 to 800 eggs during the breeding season. This large number is offset by a high predation rate.

Of those turtles which survive the hatchling stage and run down the beach to the sea only about three or four per thousand live to adult hood.

The first year of a turtle’s existence is the most critical. Though they are so small as hatchlings, their weight during their lifetime increases about 9,000 times to 400 lb or more (the weight of a human at birth increases only about 18 times during a lifetime). If a green turtle survives the first year it is relatively immune from attack by fish.

One of Dr. Bustard’s plans is to keep hatchling turtles protected from predators in pens for a year. He

slieves that doing this will increase ie survival rate of the turtles by jtween 50 and 100 times. The crease in turtle numbers could then * exploited commercially.

There is a very good world market >r turtle products. Most in demand turtle oil which is used as a jsmetics base. At present there is so a strong demand for the very >ft and durable turtle leather, due i a scarcity of crocodile leather, he calipee of the turtle—the irtilage under the shell—is dried i the sun and used as the basis I turtle soup. Japan has a high ;mand for high-protein meat-meal id turtle could contribute

gnificantly here.

The commercial demand for turtles so strong that British and American ivestors have spent $1 million in stting up the world’s first commercial irtle farm in the British West Indies, hich has almost been denuded of

s natural turtle population.

On Darnley Island, as well as a udy of the ecology of the natural irtle population, three of the six ilot turtle farms will be set up, to itplore the possibilities of “battery ;aring” techniques with hatchling irtles. Feeding methods similar to lose which have revolutionised the oultry industry in the last 10 years ill be used in development exped ients.

Green sea turtles start life as arnivores but after a year they

hange and become predominantly

egetarian, eating sea grass and saweed. At Darnley pilot farms the oung turtles will be kept continually s carnivores, being fed almost ntirely on fish.

On Murray Island Dr. Bustard’s esearch will be concentrated on educing the high infant mortality ate of the wild turtles. Hatchlings /ill be reared in pens for periods arying from three to 12 months, hen tagged and liberated. Their übsequent survival will then be ompared with that of hatchlings narked and liberated as they emerged rom the nest. This type of informa ion is not known about any turtle topulation in the world.

Local Islanders and Aborigines will ie trained to tag and mark the young urtles and to record information ibout them when they are recaptured n future years. Dr. Bustard believes hat if turtle farming can be carried >ut without threat to the conservation )f the turtle population, it could mean he establishment of an industry vhich the local people can manage ; or themselves.

In the fight against world hunger, scientists have learned valuable lessons from the food customs of small communities. Scientists are now investigating some isolated peoples in New Guinea who live below the normal subsistence level, yet appear to be in excellent health. In this article, an account of the early stages of a continuing research project is given by a British physiologist helping the study.