Coelacanth

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The coelacanth has been spotted in a minimum depth of about 50 metres and all other sightings have been below 100 metre. Would this mean that the coelacanth cannot servive in shellower waters.

The coelacanth is one of the most pretected species does this mean that they are also protected against captivity breeding.

i beleive that with the last sightings there were two pregnant females found, is there a project planned to monitor these new coelacanth, if so why? I feel they should be left alone until way after they were born.

Could it be established as to how often they breed and how long before the young are born.

The 15 coelacanth that were found is this the largest school of coelacanth that was ever spotted.

-- Denver (ddomingo@oldmutual.com), September 11, 2002

Answers

Hi Denver.

AFAIK, sightings of coelacanths in anything less that ~50m have been of sick/dying coelacanths released from a handline in the Comoros.

For a discussion of bringing coelacanths into shallower waters, and keeping them in captivity, have a look at this thread.

You can read a bit about coelacanth reproduction on this thread.

It would be illegal to attempt to capture a coelacanth in South Africa - even for purposes like captive breeding. As discussed in the first thread I mentioned, it would be foolish to even attempt to do so until we have a better understanding of their biology to ensure they live long and happy lives. Although coelacanths are rare ("endangered"), they may not need any sort of captive breeding - just appropriate protection of their habitat and the fish themselves (such as what is happening in Sodwana Bay anyway).

Hans Fricke thought (it's not an established fact) that two of the individuals might have been pregnant, but until we observe a coelacanth giving birth, we can't be sure - it might have just been a fat fish! =) Also, we know absolutely nothing about the juvenile fish, so learning anything would be a big step forward; as we know virtually nothing about juvenile coelacanths, we can't really protect them either. They are thought to be born at about 30cm.

Without considerable monitoring (extremely expensive) it would be very difficult to find out how often coelacanths mate - we do know that they can have up to at least 26 pups at once, and the gestation period is estimated to be around 13 months. The "easiest" and least intrusive method for long term observation would probably be to put a low light or infrared camera on the bottom monitoring a particular cave 24 hours a day for several years (or preferably several caves). It might be nice if this was streamed to the internet as a webcam if not live stream, but the environment and depth makes it extremely challenging to deploy something like this; it would be far easier to deploy something that had to be collected after the film in it runs out, as long cables in strong current (which you would have to have for a webcam) require massive moorings (several hundred kilograms of concrete) which would undoubtedly change the habitat - not something you really want to do in an MPA. In view of the problems AfriCam had maintaining marine cameras at sea in much shallower water at Aliwal Shoal, this would be quite a major challenge, and would probably require an investment of several hundred thousand rand for equipment alone - the deeper it has to go, the more expensive it gets. (I think one of the AfriCam marine cameras (designed for about 30m) was in the region of R400,000. It broke in the South African conditions, as it was underengineered; they also continually suffered battery problems on all their marine cameras with waterproofing - a problem they cracked shortly before going belly up in the dot com crash last year).

In Sodwana, 7 coelacanths is the largest number of fishes spotted in one location; I think the Fricke team has observed slightly larger gatherings in the Comoros.

As for disturbing the fish, I think that occasional visits from a submarine is unlikely to disturb them unduly - they're very "chilled out" animals anyway, and the submarine is probably about as intrusive as a night drive in a game reserve - and much less frequent too. Tourist trips to observe coelacanths on the other hand could be quite disruptive, and would have to be quite carefully researched before they were allowed.

I hope this answers your questions!

-- James Stapley (fishwatch@ru.ac.za), September 11, 2002.


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