The Coelacanth and the Comores:
challenging the myth
Robin Stobbs
 An over-arching quest in JLB Smith's life was the hunt for "for the
home of the coelacanth". (Smith, 1956. p.51). A few quotes from Smith's
book at the beginning of this article shows the progression of his notion that
the Comores was home to the coelacanth. Since that time the idea that the Comores
was home to the coelacanth has largely remained unchallenged until now.
 "Even
though the discovery of this second coelacanth at the Comores (sic!), and the
information gleaned by Hunt, appeared to pin-point that area as the home of
those animals, it was clear that they could scarcely be abundant there. Although
it was true that this Comoran coelacanth had been found in the type of
environment which satisfied every condition I had deduced and predicted, I knew
only too well that a coelacanth in any place does not necessarily mean that it
is at home." …"At the same time, however, the evidence that
coelacanths were caught occasionally indicated that if their true home was not
at the Comores themselves, it would not be so far off this time, and there was
all the more likelihood that this might be found more easily. The field of
search would certainly be greatly narrowed down." (Smith, 1956. p. 193)
"Two in
the same place. It must be their home, so that my enduring aim had been
achieved, and most of my burden would now fall on the French." …
"Now that one home of the coelacanth had been found…" (Smith, 1956.
p. 221)
"… my
heart was filled with fierce deep content, for I had shed the worry and
responsibility of the coelacanth; one of the greatest ambitions of my life, to
find the home of the coelacanth, had been fulfilled." (Smith, 1956. p. 226)
In writing this JLB Smith inadvertently created one of the largest myths to
have blighted the 'coelacanth story'. From this time on almost every author
writing about the coelacanth has referred to the Comoro Islands as the
creature's home (see also Fricke, Leskovitz, etc). Without ever having proved to
be the case, the Comoros were accepted by scientist and layman to be the home of
the fish and the Comoros coelacanth population the 'core' population.
Balon et al, 1988. "……… a second coelacanth was caught, this time at
its true home, the Comoro Islands."
Hissmann et al, 1988. "Three specimens caught at other locations
……… were probably strays from the Comores."
Bruton et al. 1992. "The Mozambique specimen could, however, be a stray
that was carried from the Comoros on the south-flowing Mozambique current."
Schilewen et al. 1993. "This result (DNA sequence) strongly suggests
that the Mozambique and Comorean (sic!) coelacanths belong to the same
population. If a separate population of coelacanths exists at the East African
coast, we would have expected substantially different fingerprint patterns…….
Thus, mitochondrial as well as nuclear markers indicate that the Mozambique
coelacanth originated in the Comorean population. An alternative explanation
would be that there is an African coastal population in continuous genetic
contact with the Comores. But this seems very unlikely."
Thomson (1991) examined the question critically, and in detail, yet still
arrived at the conclusion that "the living coelacanth may well be a true
relict species, existing in any numbers at all only on the Comores, but that if
it does exist elsewhere, it would be in the form of stragglers from Comoran
populations ….."
Bruton, 1989. "Fricke and Plante (1988) have predicted that further
coelacanth populations will not be found in the western Indian Ocean as no
suitable habitats exist other than in the Comoros, but I am more hopeful."
Leskovitz, in his website
wrote, "Coelacanths are appearing where least expected! In September 2001,
a fisherman caught a coelacanth at Malindi, Kenya. The fish was then brought to
Mombasa. This is the first confirmed find north of the Comoros Islands, and is
not easily explained by ocean currents." The presumption is that the fish
was probably a resident but the author is very wrong in assuming that the
north-flowing Somali Current could not have transported a coelacanth to Kenya
from further south - even the Comoros.
Others were more positive. Erdmann (in Weinberg, 1999) is quoted as saying,
"it is conceivable that there are more coelacanths, in different locations
across the globe. It seems highly unlikely that the living coelacanth exists
only in two small, highly disjunct populations."
But, this is all an accident of history - and a caution to scientists: beware of
jumping to conclusions based on only a few facts.
For almost 40 years following the capture of the 1952 Domoni fish, popularly
known as the "second coelacanth", all known coelacanths were caught
off the Comoro Islands of Grand Comoro and Anjouan and it looked indeed as
though it was only off these islands that the living coelacanth, Latimeria
chalumnae, was to be found.
Click on map below to see confirmed and unconfirmed coelacanth localities off
African coast.
 But, that was until a large specimen was netted by a prawn trawler off Pebane
in central Mozambique in 1991; before one was caught up in a deep-set gill net
near Toliara in Madagascar (with three further specimens subsequently coming
from the same locality); before a number of coelacanths were seen by Trimix
divers off Sodwana in northern KwaZulu-Natal in 2000 and 2001; before another
specimen was netted in a trawl net off Malindi in 2001 (and before two specimens
of a probably different species, Latimeria menadoensis, were caught 10 000
kilometres away in northern Sulawesi in 1997 and 1998).
It had long been suspected that the 1938 East London fish (popularly, but
incorrectly, named the 'first coelacanth') was a stray brought down on the
Mozambique Current, and indeed all these other WIO coelacanths could have been
distributed in this manner but surely all these western Indian Ocean (WIO)
specimens were not simple strays from the Comoros. DNA fingerprint
determinations made on some of these fish showed a remarkable homogenicity and
it was immediately thought that this was proof enough that they were strays from
the Comoros 'core' population. The picture that is touted is one of a
diminishing and endangered Comoros coelacanth population shedding unfortunate
individuals who are unlucky enough to be detached from their island home and
carried around by ocean currents eventually to be deposited elsewhere where they
run the risk of capture in trawl nets or deep-set shark gillnets.
Could this be the true picture?
I think not - and for a number of reasons I believe this is all due to an
unfortunate series of historical events and a patent disregard by a number of
scientists for some important facts.
1. Following Smith's pronouncement that the Comoro Islands were the true home
of the living coelacanth all scientific endeavour and research has been directed
at these islands and at their coelacanth population in the mistaken belief that
this was the only population group. It was inevitable therefore that nobody was
looking elsewhere.
2. Only on the Comoro Islands of Grand Comoro and Anjouan, and nowhere else
in the Indian Ocean, is the technique of deepwater nighttime handline fishing
practiced. Known to the Comorans as mazé this form of fishing was developed to
'target' (in as much as one can target a fish species) the oilfish, Ruvettus
pretiosus, known to the Comorans as nessa. Living within a similar depth
preference and competing for the same prey species, nessa and gombessa
(coelacanth in the Comoran patois) are caught by artisanal fishermen; the former
by design, the latter by accident. Since it is mazé fishing that is commonly
responsible for the occasional and accidental gombessa catch and since this form
of fishing is not practiced elsewhere it is inevitable that coelacanth catch
records from the Comoros far outnumber any other locality.
3. Coelacanths are believed to have been extinct for some 60 to 70 million
years; Latimeria's closest known fossil relatives, Macropoma from Upper
Cretaceous chalks in England and Megalocoelacanthus from the Upper Cretaceous
outcrops of central Alabama and Georgia states in the USA both died out some 75
million years ago. The islands of the Comoros are only 0.13 to 5.4 million years
old (Grand Comoro and Mayotte, with Anjouan and Moheli 3.5 and 2.75 million
years respectively) (Emeric & Duncan, 1982, in Forey 1998) so one is left
with the question, "What were coelacanths doing during the 65 million years
it took for the volcanoes forming the Comoros to reach the ocean surface?"
It is clear that they had to have been living elsewhere. Two pieces of ancient
Gondwanaland, Madagascar and the African continent seem the most likely regions
for our ancestral coelacanth habitats. Surrounding Madagascar and off the
African east coast are ocean currents that might easily explain a widespread
distribution throughout the entire WIO with the possible exception of the
Mascarene Islands and the Seychelles and the islands to the east of Madagascar.
4. A collection of anecdotal accounts of coelacanths that were observed or
caught, and which cannot be verified though every aspect of the accounts points
to their authenticity, shows that Latimeria, though possibly nowhere abundant,
is probably widely distributed throughout the WIO (see Fig.1).
References on the topic:
Albert, J., 2001. Pers com.
Balon, E.K., M.N. Bruton & H. Fricke, 1988. A fiftieth anniversary
reflection on the living coelacanth, Latimeria chalumnae: some new
interpretations of its natural history and conservation status. Environmental
Biology of Fishes, 23(4): 241-279.
Bruton, M.N., 1989. The living coelacanth fifty years later. Transactions of
the Royal Society of South Africa. 47(1): 19-28
Bruton, M.N., A.J.P. Cabral & H. Fricke. 1992. First capture of a
coelacanth, Latimeria chalumnae (Pisces, Latimeriidae), off Mozambique. South
African Journal of Science 88:225-227, April 1992.
Forey, P., 1998. History of the coelacanth fishes. Chapman and Hall, London.
Hissmann, K., H. Fricke & J. Schauer, 1998. Population monitoring of the
coelacanth (Latimeria chalumnae). Conservation Biology, 12(4): 759-765.
Leskovitz, F., 2002. http://members.tripod.com/glenthorne/coelacanth.html
Schilewen, U., H. Fricke, M. Scharti, J.T. Epplen and S. Pääbo. 1993. Which
home for coelacanth? Nature 363: 405, 3 June 1993.
Smith, JLB., 1956. Old Fourlegs. Longmans, Green, Readers Union edition.
London 1957
Smith, JLB., 1956. The Search beneath the Sea. Henry Holt and Co., New York.
Thomson, K.S., 1991. Living fossil; the story of the coelacanth. W.W. Norton
& Co., New York.
Weinberg, S., 1999. A fish caught in time; the search for the coelacanth.
Fourth Estate, London.
These being just a selection of the many references to the 'home' question.
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