Science sub spots secretive Coelacanths
Staffer
GSLWP
You may have notice a large ship anchored off the shores of Sodwana from the
15th April – 11th May this year.
This was the research ship the FRS Algoa on its third research expedition
for the Coelacanth Programme.
The amazing first discovery of a 'living fossil' coelacanth in 1938 by Dr.
Marjorie Courtenay-Latimer in the Eastern Cape has since then has stimulated
great interest in this curious and little understood fish.
The coelacanth was thought to be long since extinct when the first specimen
was found in 1938 and subsequently others along the eastern coast of Africa
(one in Mozambique and two in Kenya) and the off-shore islands of the Comores
and Madagascar.
Since it became known that coelacanths lived in the underwater canyons offshore
of the GSLWP, scientists have been trying to obtain an understanding of the
number of these fish, their locations, and the habitats that they live in
offshore of the Park.
It is also of interest whether the population living here is resident and
is a viable breeding population.
It has been hypothesised that the colony of coelacanths living offshore the
Park were washed down by the Mozambique current from their regular habitat
in the western Indian Ocean around the Comoros islands.
One of the goals therefore is to try and obtain genetic material from the
fish in the form of scales in order to undertake tests to link the fish with
their counterparts further north.
In this and the previous expedition, Coelacanths were monitored by means of
the two-man submarine, Jago which was lowered down into water from the ship.
Video footage of canyon habitats and biological communities living there was
recorded.
The submarine is also equipped to place acoustic tags on the fish for behavioural
studies. This has been shown to be an effective method of locating coelacanth
caves and discovering other fish.
The information that is gained will feed into the GSLWPA Coelacanth Management
plan so that these rare and unique fish can be conserved and protected as
part of the World Heritage Site.
Third foray
The
results of the third expedition released by Dr.Tony Ribbink, Co-ordinator
of the Coelacanth Programme revealed that there are at least 18 coelacanths
in Jesser and Wright Canyons.
Scales were collected from three individuals. These were divided for studies
in population genetics, mainly kin relationships and genetic variability to
establish conservation status. Live cells were scraped off some scales and
grown in a tissue culture for genome research. It is the first time that cells
have been cultured from coelacanths anywhere in the world and opens up numerous
possibilities for genome resource studies, which is an achievement of note.
It has been shown that it is feasible to collect cells from live coelacanths
and grow tissues.
Prof Tony Ribbink reported that although the Jago offers the best and safest
manner in which to explore the canyons, it is an incredibly slow process.
He stated that “We have only just begun to understand the South African
coelacanths and their habitat”.