After the long time since the first one was caught has not attempt been made to capture one alive. I am at present doing a project for my School ( Felixton College) near Empangeni and I would love some more information as your education page has not started yet....thank you

-- Savannah Meyer (angel.enterprises@saol.com), April 28, 2002

Answers

Hi Savannah,

Coelacanths caught on a line and hauled up from the depths seem to inevitably die - there may be several reasons for this.

Coelacanths live in deep, fairly cold water underneath a typically balmy tropical sea - i.e. they live at about 18 degrees C whilst the surface temperatures are about 24+; whilst we were in Sodwana Bay sea surface temperatures were about 26 degrees.

Bringing a coelacanth into warmer water is stressful, not only because they are struggling on the end of a hook, but also because warmer water is a double edged sword - warmer water contains less dissolved oxygen (which the coelacanths need to "breathe"), whilst the warmer water speeds up their metabolism, making them need more oxygen; it is thought that coelacanths may actually be in effect suffocating as they are brought to the surface.

Other potential problems involve the great depths they are brought up from; you may have heard of the "bends" which unfortunate SCUBA divers may suffer from, where gases which have dissolved in their tissues at depth come out of solution as they come back to the surface, causing little air bubbles which result in a lot of pain, or in severe cases, death. This so called barotrauma may also affect the coelacanths. Fish caught at depth must be brought up very slowly - sometimes even over several days to avoid such problems. The other solution is to put the fish in a pressure tight container and then release the pressure very slowly back on the surface, similar to what is done with really deep sea divers.

An expedition was sent out several years ago by a Japanese aquarium to capture a live coelacanth in the Comoros to display in their aquarium; they didn't manage to catch any. Hans Fricke and his team were studying coelacanths in the Comoros at the time, and put stickers in the traps asking the Japanese not to catch coelacanths; apparently they were very confused as to how these stickers got into the traps! (They had no idea Jago was diving there).

Coelacanths are a rare and endangered species. Until we know a lot about their physiology (the way their body works) and needs, it would be a bad idea to even attempt to keep coelacanths in captivity. Until the point at which there is a well planned expedition, and when we have sufficient knowledge to make it a success - and ensure a long, healthy and happy life for the coelacanth in captivity, it would not be a good idea to try to capture and keep a coelacanth in captivity, as interesting a display as it might make. Also, we need to know that taking that coelacanth out of its population will not harm the population in any way - this is always an important consideration with an endangered species.

Given their propensity for gathering in groups in caves, they may be "social" animals and need company - so we would need to perhaps catch several.

However, even once we have caught a coelacanth, and kept it in captivity, there is a potential risk that a "coelacanth fever" will grip aquaria worldwide, and after sufficient collecting, we might end up with coelacanths all living in fishtanks, and not in the sea!

I hope this answers your question!

James.

-- James Stapley (fishwatch@ru.ac.za), May 06, 2002.