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MARGINALIA

The Coelacanth: Act Three

Keith Thomson

Act Two: The Plot Thickens

By 1966, some 50 specimens had been caught by Comoran fishermen, using traditional hand lines with a single baited hook at between roughly 100 and 500 meters. In fact, no Westerner had ever caught one (or has yet). It seemed that Latimeria were mostly caught in the first three months of the year, always at night and only from two islands. The idea became popular that they really lived at depths beyond the fishermen's reach and migrated to lesser depths at night, following food species. Then doubt started to grow: The fishing statistics are not an index of the fish's behavior, but rather of the fishermen's! Fishing the deep slopes of these volcanic islands, where there is no protective reef, is dangerous work in a dugout canoe, but the seas are relatively calmer in those months. Despite monetary incentives, the locals are not usually fishing for Latimeria, which is inedible. They are fishing for the more common and reliable Ruvettus pretiosus, prized for the medicinal value of its oil. So everything we know about the distribution of Latimeria may actually be the area of accidental overlap between its range, the range of Ruvettus and the behavior of the fishermen.

In 1966, through another set of strange events, I managed to get to my laboratory at Yale University a freshly frozen specimen. The Comoro Government had decided to raise some foreign currency by selling specimens, and they wrote to museums worldwide to see whether there was any interest. My view was that we already had enough formalin-preserved material; surely a specimen could be frozen instead. Shortly a telephone call from the U.S. Department of State announced that a mysterious shipment addressed to me had become stranded in Marseilles. Only later came the letter from the Comores saying that a specimen had been caught, frozen and put on a passing fruit boat: "Please send $300." Luckily the smart work of the U.S. Commercial Consul in Marseilles saved the day and the fish. A loyal Yale alumnus, he took it from the boat in an embassy car to a frozen-food warehouse and phoned for instructions.

The fresh coelacanth tissues from that specimen gave us a great deal of information about the biology of Latimeria and, from that point on, Act Two became defined by the study of the living fish rather than by its anatomy. Quite naturally, dreams turned to capturing a live specimen. The 1969 expedition failed. In 1972, a new British-U.S.-French venture went to the Comores. At the very end of the trip, a fisherman named Madi Yousouf Kaar brought a coelacanth to shore, alive. It was turned out into a special tank, filmed and observed for several hours.

Pressure for more expeditions grew, and, indeed, further success seemed assured, except that soon afterwards the Comores descended into a political chaos from which they have yet to emerge. Field research in the Comores essentially stopped—except for the efforts of one determined individual.

Dr. Hans Fricke of the Max Planck Institute at Seewiesen, Germany, set out to do what had been dreamed of many times before—to film coelacanths underwater. The obstacle had always been that research submersibles, such as Woods Hole Oceanographic's Alvin, are expensive to operate. So Fricke built his own submersible and, with a private yacht as his mother ship, went to the Comores. Where to look was obvious even if it was based on a flawed analysis. And he succeeded brilliantly, first time. He found live coelacanths between 100 and 200 meters down, living in caves in the deep submarine sides of the volcanic islands.

Coelacanths turn out, as predicted by muscle biochemistry, to be dull creatures, not given to leaping about at high speed, but slowly moving using their paired and median fins in the sculling actions first crudely seen in the 1972 films. But Fricke did not succeed in capturing any major behaviors: no feeding, no copulation, no courting, no fighting off predators. In fact, Fricke concluded that coelacanths lived in every sense a rather empty existence and that the associated fauna were very sparse: no sharks, not much food. Fricke did not observe any juveniles in the cave environment. He did find a vertical nocturnal migration, presumably for feeding—but downwards instead of upwards. Fricke's work seemed to show that coelacanths live in very specialized, sheltered habitats where the lava is most recent and where, therefore, there is no fringing reef—all contributing to create an ecologically depauperate setting. No wonder we hadn't caught any off the richer coral islands to the northwest. And this seemed to confirm that the first South African specimen had been a stray, carried down the Mozambique Channel. In 1988, I forecast that if new sources of coelacanths were to be discovered in the future, they would be on other very young volcanic islands nearby—for example, Europa and Bassas da India.




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