|
Coelacanth: An ancient fish species in Tanzania`s waters
2007-05-12 09:47:37
By Lusekelo Philemon
After surviving for millions of years, the coelacanth fish species fossil fish is threatened by high demand for wild fish, rapid population growth and sophisticated commercial fishing fleets in the Indian Ocean. Our writer Lusekelo Philemon expounds on the issue. Read on…
The looming malpractices by local fishermen off Tanzania’s waters weakened the preservation initiative of this wonderful fish species in sub-Saharan Africa.
However, global statistics show that rapid population growth in developing countries like Tanzania increased fish consumption and hence put at risk the survival of rare species like coelacanth.
In addition, changing of life style in the least developed countries because of rapid urbanization growth which forced people to adjust their dietary system slow down the initiatives towards sustainable preservation of the endangered fish species. Fish accounts for 60-70 per cent of annual protein intake.
Coelacanths, therefore, are under intense threat of extinction as local communities along the coast especially artisanal anglers are not aware of the potential benefits of preserving this endangered fish specie.
The tropical waters of Tanzania have emerged as the favoured spot for scientists and other stakeholders seeking new population of coelacanth, an ancient fossil fish that has been swimming the seas for 400 million years.
Since 2003, fishermen off Tanzania have caught more than 30 coelacanths, whereby recently another coelacanth was caught at Masimbati village (Ras –Matunda Faranandis). This has made the dreams of Mnazi Bay Ruvuma Estuary Marine Parks (MBREMP) come true.
The recent coelacanth was caught by shark nets at the depth of 250 meters with the following measurements; weight; 61 kg, length; 1.6 m, length of the limb like pectoral fins 40 cm, length of the limb like pelvic fins 23 cm, length of the lobed anal fin 26 cm, rayed fan like first dorsal fin 21 cm, lobed second dorsal fin 28 cm, head circumference 94 cm and abdominal circumference 112 cm.
Senior Communication`s Information Officer for Marine Parks and Reserves Tanzania, John Mapepele, confirmed the catch of this rare and wonderful fish species off Tanzania.
He explained that, the existence of coelacanth populations in Tanzania is a result of proper protection of the marine parks and reserves.
``This is one of our own successes since the establishment of marine parks and this will be the second marine park to conserve this fossil fish in Africa,`` Mapepele said, adding that, ``the recent catch of coelacanth at Masimbati village was an accidental case.``
He said: ``There is overwhelming evidence that our sea has many of coelacanth fish (fossil fish) species. We are sure there are more populations of coelacanth in our country,``
Coelacanth has been categorized as one of the fish species that are exceptional and need protection like rhinoceros in the terrestrial ecosystem.
Mapepele further explained that, raised public awareness seemed to be behind the surge of Tanzanian fishermen coming forward to report coelacanth catches though the trend could also point to more offshore fishing in response to depleted inshore stocks.
Tony Ribbink, the head of the African Coelacanth Ecosystem Programme (ACEP) was quoted saying that fishermen were netting them off Mozambique but not reporting the catches.
Scientists say coelacanths, which live in underwater caves (submarine caves), deep reefs with temperatures below 21 degrees Celsius and canyons at depths of between 100 and 300 metres, may provide clues to life`s distant past, while the search for them deepens our understanding of the western Indian Ocean.
The coelacanth was around long before the dinosaurs and was long thought to have died out with the massive beasts over 65 million years ago.
The one was netted by a fishing trawler off South Africa in 1938 a catch that shook the scientific world and was widely regarded as the zoological find of the 20th century.
They were subsequently found to be near the Comoros Islands off Africa\'s east coast and were first observed there in their natural habitat from a submersible vessel.
In 2000, scuba divers stumbled across South Africa\'s coelacanths in Sodwana Bay off the country`s northeast coast.
The under-water canyons of Tanzania, Mozambique, Kenya and Madagascar all have to be mapped.
A sophisticated ship-based sonar system is used for such mapping.
The conference also heard that the 1938 specimen, long believed to have been a ``stray`` dragged down to South Africa`s southern coastline by currents, may in fact have been on the edge of its range.
Oceanographer, Mike Roberts, was also quoted saying that recent research showed the popular belief that there was a westward moving current off Mozambique was not true.
``The Mozambique current does not exist and so coelacanths could not have been washed down to East London from the Comoros. The currents off Mozambique move in big swirls,``he said.
Nevertheless, he says the coelacanth\'s favoured temperature and depths seemed to extend down to the southern coast of South Africa.
At first, the coelacanth was netted at the island of Songo Mnara, off the coast of Tanzania. This was the first report confirmed of a coelacanth being caught off Tanzania.
Combined with catches off Kenya, Comoro, and Mozambique and hence at Sodwana, South Africa, raised the question of permanent coelacanth colonies off East African coast, now apparently confirmed.
Recent report show that, earlier last month a coelacanth was caught off southern Tanzania at Songa Mnara Island, followed by a catch off Moheli in the Comoros and then just a day later, another in Hahaya, north of Grand Comoro.
The finds extend the known habitat range of this fish. Coelacanths have never been found at Moheli and the only previous capture off Tanzania was an unconfirmed one at Mafia Island.
The fish found in Tanzania was caught by local fishermen in a net in just 100m depth of water according to South African James Taylor.
Taylor was visiting the island when he recognized the fish amongst many on the island left out to sundry. The fish had already been cut with all its insides thrown away.
Rumisha, Manager of the Marine Parks and Reserves Tanzania and colleague, Prof. Bwathondi, positively identified the fish and worked around the clock to try and preserve the specimen. According to Taylor the fish was 132cm and without its insides weighed 22kg.
The coelacanth finds follow almost immediately the NEPAD research and reconnaissance visit of the African Coelacanth Ecosystem Programme to Mozambique, Tanzania, Comoros and Madagascar.
The discoveries in those areas are thus prompting scientists, including ACEP project manager, Dr Tony Ribbink, to speculate whether the finds are a coincidence, a response to heightened awareness, or simply that the discoveries are now reported to the ACEP instead of going unrecorded.
The African Coelacanth Ecosystem Programme was launched in 2002 after the discovery of a colony of coelacanths in the shallow waters of the Greater St Lucia Wetland Park in KwaZulu-Natal, South Africa.
Preserving this fish species from extinction needs collective efforts from all stakeholders grass-root levels to regional levels.
More awareness campaigns are to be done to retain and preserve this endangered fish species which if preserved properly would contribute to the country and regional socio-economic development.
The coelacanth populations in East African region are exceptional which in turn would attract more tourists and hence improve people`s livelihoods in Tanzania and its neighbouring countries that share the sea Kenya, Mozambique, South Africa, Comoro and Seychelles.
|
