| The Magazine of the CALIFORNIA ACADEMY OF SCIENCES |
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Letter From The Field Beneath Forbidden Seas John E. McCosker Despite all that is known about the Atlantic Ocean–its circulation, its chemistry, and its life forms–Cuba, its largest island, remains an Antillean enigma. While oceanographic research has expanded dramatically in the past 50 years, political disagreements have left Cuba behind, without the modern equipment or funds necessary to understand the largest and perhaps most significant piece of the Caribbean puzzle. Knowing that larvae and currents don't recognize national boundaries, marine biologists have long wanted to sample Cuban coastal waters, which are the source of many of the fish and invertebrates that ultimately drift or swim to Florida. And Cuban scientists, whose predecessors were among the first to document and study the natural history of the New World, have been frustrated by their inability to sample their own backyard. Biodiversity tends to be concentrated in the tropics, and because of its size and geological history Cuba has the greatest abundance of species of any Caribbean island. Although the island is comparable to Oregon in size, it has nearly as many vascular plants (~15,000 species) as the United States and Canada combined (~18,000 species). And more than half are endemic to Cuba, with even higher levels of endemism (greater than 90 percent) recorded for terrestrial mollusks, ants, and amphibians. Life on Cuba has had at least 42 million years to adapt and evolve to its nearly 44,200 square miles of inhabitable space. Whatever existed there 60 million years ago when the Cretaceous–Tertiary bolide collided with the Yucatan was probably pummeled by waves more than a thousand feet tall. That impact was probably no less significant than the arrival of the first humans, reaching Cuba from South America about 5,500 years ago. Those hunters, gatherers, and fishers known as the Guanahatabey and Sibney, were joined and succeeded by the Taînos, a branch of Arawak Indians, 750 years ago. The legacy of those early aboriginals is remembered by such sonorous words as Guanahacabibe, iguana, caiman, and Cuba. But their impact was trivial compared with that of Christopher Columbus, who saw Cuba during his first voyage and subsequently landed there in 1493. His second voyage brought sugar and domesticated animals–dogs, cattle, sheep, horses, and pigs–that would forever change the flora and fauna of this benign insular laboratory. My colleagues and I looked forward to documenting what remains of this rich biodiversity and to testing if levels of uniqueness and biodiversity underwater are comparable to those on land. Sensing a thaw in upcoming international relations, we set about in 1996 to join forces with Cuban colleagues and planned to bring the Harbor Branch Oceanographic Institution's (HBOI) research submarine Johnson Sea-Link and its support ship, the 204-foot Seward Johnson, to explore the Cuban coast between sea level and 3,000 feet. (This is the same ship and submarine that supported my deepwater research in the Galápagos (see "A half mile down," Pacific Discovery, Winter 1997). After nearly two years of negotiations and explanations to Cuban ministries and U.S. Departments of State and Treasury, in December 1997 we were allowed to sail from Florida directly into Cuban waters. In doing so, we would be the first extensive oceanographic expedition to work in Cuba in 31 years. Funded by the Discovery Channel, we assembled a team that included underwater and topside filmmakers, led by Academy Research Associate Al Giddings and James Lipscomb, respectively; Richard Fagen, a recently retired professor of Latin American history from Stanford University; and HBOI scientists Grant Gilmore, Shirley Pomponi, Edith Widder, and Tammy Frank, plus C. Richard Robins (University of Kansas), Rodolfo Claro and Pedro Alcolado (Instituto de Oceanologia in Havana), and the author. After clearing customs in Santiago de Cuba and welcoming our Cuban colleagues on board, we went back to sea and quickly established a routine of two daily submersible dives (separated by battery recharging, oxygen replacement, and specimen curation), daytime and nighttime scuba dives, and excursions into the shoreline to sample reefs and mangrove communities. We cruised the southern coast studying offshore seamounts and banks, and visited the Golfo de Guacanayabo, and the coral chain of the Jardines de la Reina. Then, as the New Year approached, we rounded the west cape and entered the angry waters of the Yucatan Channel, where conditions were too rough to work at sea, let alone launch the submarine. So we hammered into the heavy seas on our way to Havana. Here, we were met not by enthusiastic throngs but hungover revelers wandering along nearly deserted streets. We had arrived the day after the doubly celebrated New Year's Eve and the 39th anniversary of the Day of the Revolution. While in Havana, I pursued the answer to a mystery that had long intrigued me and many others, that being to confirm or deny that the largest white shark (Carcharodon carcharias) ever caught was in Cuban waters. Known as El Monstruo de Cojimar, the giant was captured in deep water by a fisherman in 1945 along the north shore off Cojimar. Photographs were published that, not unlike most fishing photos, showed the humans far in the background and the fish's nose close to the lens. The renowned Cuban ichthyologist Luis Howell-Rivero reported that it was more than 21 feet in length and weighed 7,302 pounds. His student, Dario Guitart-Manday, published a brief article with fuzzy photographs of the shark and one of its large teeth. Most ichthyologists remained sceptical. White sharks are rare in tropical waters, and no evidence other than the fuzzy photos, long since lost, is known to have existed. Richard Ellis and I, in our book Great White Shark, agreed with Bishop Museum ichthyologist John Randall that, lacking additional evidence, the largest Carcharodon on record was likely to be a purported 20-22-foot-long Australian monster from Kangaroo Island. (Though it, too, is a fishy mystery because the shark was said to be larger than the fisherman's boat and only its head and pectoral fin were saved.) Rodolfo Claro had already told me that Guitart-Manday was living in Havana and had a remarkable memory of all matters concerning Cuban ichthyology. Long-since retired, Guitart-Manday and his wife live in an old villa surrounded by tropical plants, mildewing books, and ichthyological memorabilia. When I asked him about Carcharodon, his eyes twinkled as if reminded of an old friend. Having been responsible for an active commercial shark fishery since the 1950s, he knew of only two Cuban specimens: El Monstruo, and a 5,000-pound female taken in 1975 at the surface along the north coast. He was confident that El Monstruo was as heavy as reported, and sheepishly admitted that although the photographs were lost, a single tooth remained–in his wife's jewelry box. She retrieved a silver chain with a tortoise-shell-capped, slightly misshapen (as teeth from large sharks often become), fourth upper lateral tooth that was obviously from an enormous white shark. About 45 millimeters tall, it appeared smaller, as I recalled, than the teeth of the Australian shark. I left with the mystery neither adequately solved nor refuted, but a certain nervousness during my subsequent scuba dives in Cuba. While at anchor one evening in Havana we were advised on short notice to prepare for an important and interested visitor. Closely following the arrival of a squad of khaki-clad, kalishnikov-bearing soldiers was amateur ichthyologist and Cuba's president Fidel Castro Ruz. Whatever one feels about his politics and actions, one cannot fail to be impressed by his charisma and the breadth and wealth of his knowledge. Educated as a lawyer, he spent much of his youth underwater with a facemask and trident, or above water with a hook and line. His non-political visit lasted nearly three hours and comprised a non-stop barrage of questions (ranging from the biomedical potential of tumor-inhibitory sponges and coelenterates to the extinction rate of species on nearby islands), statistics, statements, and profound pontifications about world population, interspersed with an occasional humorous observation about the behaviors of marine animals and humans. While examining specimens that we had collected, or fiddling with the submarine's complicated control panels, he convinced us all of his fascination with technology and the sustainable management of Cuba's marine resources. He had seen all of Al Giddings' natural history films, and was prepared to ask me about Cuba's shark fisheries ("unsustainable due to the low reproductive capacity of elasmobranchs?" he asked), the potential of freshwater eel culture and export ("would increasing the abundance of local Anguilla put other species at risk?"), a question that caught me completely off guard about coldwater salmon culture ("what if we brought cold, deep Cuban waters to the surface in order to imitate the Chilean success with salmon rearing?"), and was El Monstruo still the largest white shark on record? (Clearly a matter of Cuban pride.) His visit finished in the blink of an eye. This was a carefully unorchestrated visit, and there was no mention of politics except for mine as he was leaving. Castro advised me to beware of Cuban sharks, and I responded "Señor Castro, politicians are more dangerous than sharks." "Verdad," he said with a smile. Truly. The U.S. embargo and the more recent departure of Soviet capital and technical support have made fuel a scarce commodity for Cubans. Although this shortage may not be appreciated by Havanans packed like sardines on a guagua (public bus) or Santiagans being slowly pulled by a horse-drawn taxi, it has protected much of the marine environment from the depredation and overfishing caused by cheap and abundant fuel. Much of Cuban fishing occurs in the coastal waters accessible to sailboats. Perhaps the finest example of ecological good fortune, assisted by some careful planning, is that of the chapingorro lobster fishery. I was surprised to discover that Cuba is the world's second largest supplier of spiny or rock lobsters (distantly related to Homarus americanus, the Maine lobster), trailing only Australia, which has a coastline many times more extensive. Yet unlike its competition, the Cuban fishery has sustained an annual output of nearly 12 million pounds for three decades. Prior to the Revolution, Cubans speared or trapped rock lobsters for the tens of thousands of annual American tourists. Neither lobsters nor lobster fishermen profited from this practice due to the low prices paid by the middlemen to the lobstermen as their canoeloads of dead crustaceans lay spoiling in the tropical sun. Unable to bargain aggressively, lobstermen instead fished harder, particularly during the most harmful season, the langostina's annual gathering and reproductive march. After the Revolution, lobster fishery practices changed dramatically. Proper baseline studies of the abundance, distribution, and life history of the Caribbean spiny lobster (Panulirus argus) were undertaken. It was discovered that much of the Panulirus population along the Florida coast originates along Cuba's south coast, hatches, and drifts as larvae with the southeasterly currents that feed our shores. And along with those lobster larvae are the planktonic juveniles of many other invertebrates and fishes that ultimately settle on Florida reefs. In the early 1960s, lobster fishing cooperatives were formed, limits established, and rules enforced, particularly the prohibition against capture during the reproductive season, and protection of juveniles and egg-bearing females. And finally, it was decided that all langostina must be alive when sold, requiring modern boats with onboard tanks and onshore holding, receiving, and transporting systems. President Castro told me with pride that he was personally involved with the design of the Cayo Largo, a 60-foot-long wood and fiberglass boat used by fishermen along the southcoast cay of the same name. The Cayo Largo has an enormous well, or vivero, for holding live lobsters during the month the boat spends at sea gathering lobsters from the fishermen who work along the shallow flats of the highly productive Golfo de Batabanó. Diving down, I could see the antennae of several dozen nervous one to four pounders waving out at me, their owners digesting the meals they had scavenged during nighttime feeding forays. Strict enforcement of the restrictions, quotas, and limitations, as well as careful monitoring of the health and abundance of lobster larvae, have allowed Cuba to harvest five to ten million adult lobsters annually, without depleting the resource. At the end of the expedition, we gathered in the ship's mess before the Cubans departed and tried to summarize our initial findings to see if any cross-phylal patterns might have surfaced. We ichthyologists reported that, in general, southern Cuba is rather depauperate in fish, particularly in deep water. This did not appear to be the result of overfishing (although many large nearshore fishes like groupers had disappeared, and sharks were inexplicably rare offshore) but rather related to the energy available within the ecosystem. Based on my comparable experiences in the Galápagos, I estimated that each dive in Cuba encountered but a fraction of the abundance of Pacific individuals and species. We did collect as many as 22 fish species previously unrecorded from Cuban waters, and another four that are probably new to science. The sponge biologists were more excited than the ichthyologists, perhaps indicative more of the lack of prior knowledge rather than a treasure trove of porifera. Systematist Pedro Alcolado estimated that the submersible and scuba divers collected 47 sponges unknown from Cuban waters, and of those, at least four and perhaps as many as 21 are new species. Shirley Pomponi was able to isolate a bioactive compound from a sponge that was similar or identical to a tumor inhibitory isolate she had discovered elsewhere; she will be pursuing this in the laboratory. Midwater biologists Edie Widder and Tammy Frank were surprised and disappointed by the clarity of the seas along the southern coast. Such transparency demonstrates the low productivity of those waters. But the bioluminescent creatures they captured made up for it, as we often observed in the glow of their faces after midnight net tows and long nights in the lab. All in all, our efforts provided a brief snapshot of Cuba underwater, but it was a voyage of discovery. We were able to spend a month in waters previously forbidden, with tools and techniques unavailable to our Cuban colleagues. Armed with documentation of the kinds, abundances, and behaviors of species, scientists can focus their research and provide decision makers with the ability to make informed choices. John E. McCosker is Senior Scientist and Chair of the Department of Aquatic Biology at the California Academy of Sciences |
Winter 1999
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