Otters Among the most playful and intelligent of all animals, otters have been unfortunate in having durable, waterproof fur that is highly desired for coats, jackets and other fur items. Otters of 13 species are found on all continents except Antarctica and Australia, but throughout their ranges, they are thinly distributed and vulnerable to overtrapping.
Many species have incurred great losses from the fur trade. All species of otters (family Lutrinae) are now listed on CITES, with five species and one subspecies on Appendix I, and the remaining on Appendix II. Four species and two subspecies are listed on the U.S. Endangered Species Act. Seven species were listed in the 1996 IUCN Red List of Threatened Animals (one as Endangered, four as Vulnerable and two as Near-threatened) (Baillie and Groombridge 1996). The downward trend of otters was reflected in the fact that the 2000 IUCN Red List of Threatened Species listed 11 species (four as Endangered, three as Vulnerable, one as Near-Threatened, and three as Data Deficient). This represents 85 percent of all otters. The large number of species that are threatened is an indication of the massive declines that otters have suffered over the past century, in large part due to the fur industry.
The Sea Otter (Enhydra lutris) is a large marine species, heaviest of all otters, weighing up to 45 kilograms (Reeves et al. 1992). Living in groups called rafts that float just offshore, they were nearly exterminated throughout their range by the fur trade. Killed for their extremely valuable pelt, pursuit of these otters during the 18th and 19th centuries was among the most destructive and thorough of any in the history of the fur trade. Originally numbering from 250,000 to 300,000, Sea Otters once occurred throughout the North Pacific rim, from Baja California, Mexico, north along the coasts of North America to Alaska, the Aleutian Islands, Russia and the northern Japanese archipelago (Reeves et al. 1992). The German-born Arctic explorer George Steller encountered thousands of Sea Otters during his stay on Bering Island in 1741; his party killed and ate 700 animals, describing adults as “fairly good to eat,” and the young as “dainty as suckling lamb” (Peck 1990). Steller's navigator, Vitus Bering, considered the soft, thick pelts a resource which could provide great potential wealth, bringing 900 pelts to Russia (Allen 1942). When Catherine the Great, Empress of Russia, saw one of the skins, she ordered a cloak of Sea Otter to cover her from throat to ankles, launching an onslaught of hunting. Many pelts were traded to the Chinese, who valued them highly (Allen 1942). By the late 19th century, its pelt sold for up to $165, and as it became rarer, the price rose to $1,125 by 1903 (Nowak 1999).
At first, Sea Otters were easy to kill, having no fear of humans (Peck 1990). One Russian traveler wrote, "They covered the shore in droves; they would come up to our fires and would not be driven away." Sea Otters approached the Russians on Bering Island and rubbed their noses against the legs of sailors, who immediately bludgeoned them to death (Nickerson 1984). "When it receives a vigorous blow upon the head," one hunter observed, "the otter falls upon the ground, covers its eyes with its paws, and keeps them so, no matter how many times it is struck." The native Aleuts considered them to embody spirits of their own dead, and at first refused to hunt them at all (Peck 1990). Russian seamen forced the Aleuts to produce otter pelts by threatening to rob and pillage their villages and take their women hostage for the furs (Peck 1990). If Aleut hunters failed to produce the furs, the hostages were raped and murdered (Peck 1990).
The Sea Otters were shot as they lay in kelp beds, clubbed when they surfaced from dives to breathe, and netted in wide coarse nets (Allen 1942). On land, they were pursued as they sought shelter among rocky shores, and then clubbed to death. Perhaps the cruelest method was the capture of a pup when the mother dove for food. A cord was tied to the foot of the pup, with fish hooks placed close to its body and attached by the cord. Retiring to the shore, the hunter would pull the cord, hurting the pup so it would cry, bringing the mother, who would become caught in the line or hooks or, so occupied in freeing her offspring, easy prey (Nickerson 1984). The killing of 15,000 Sea Otters by the Russian and English near Bering Island caused the otters’ extinction on the island, and they remain absent there today. After less than a century of intense hunting, only 15 otters were found and killed in the entire Aleutian chain in 1826. During the next decade, however, new herds were discovered in Alaskan waters, and in the mid-19th century, about 5,000 Sea Otters were taken per year. Over the 30 years that they were hunted in southern California, an estimated 50,000 were taken, with at least 5,000 a year killed in San Francisco Bay (Nickerson 1984). By 1833, only 54 Sea Otters were found in the Farallon Islands off California; they were soon killed off. This hunting was carried out by enslaved Aleuts brought from Alaska (Nickerson 1984).
By 1900, the Alaska Commercial Company, operating five trading posts and 16 schooners, was able to find only 31 Sea Otters, whose pelts were sold at $1,000 each (Allen 1942). In 1910, Sea Otters finally received protection under the North Pacific Fur Seal Act, but they had reached the verge of extinction, numbering, in the opinion of biologist Karl Kenyon, only between 1,000 and 2,000 animals (Nickerson 1984). They had been hunted out of much of their territory, including the long coastline from southeastern Alaska to northern California, where a tiny remnant population survived. An estimated 500,000 Sea Otters had been killed between 1740 and 1911 (Reeves et al. 1992). The scattered remnants of this species continued to be killed wherever they were found. When small numbers of Sea Otters were spotted between the 1890s and 1917 in the waters off San Luis Obispo and Monterey, California and near islands off Baja California, Mexico, they were immediately shot (Nickerson 1984). Although the Russians predominated in the hunts, Americans, alerted by Captain James Cook in the 18th century, were almost as responsible for the near-extinction of these beautiful animals.
In the 1950s, after an apparent recovery of the species in Alaska, the state Department of Game began a program of experimental harvesting; from 1962 to 1971, 2,933 pelts were taken for zoological data and for possible sale in the fur market (Reeves et al. 1992). Their world population numbered about 32,000 by 1965 (Nickerson 1984), and hunts were ended in U.S. waters by passage of the Marine Mammal Protection Act of 1972. Take by native Alaskans is permitted under certain conditions, and some native hunters have killed large numbers of Sea Otters (Reeves et al. 1992). Populations totaled an estimated 100,000 to 150,000 in the early 1990s, with the largest numbers off Alaskan coasts (Nowak 1999). The Sea Otter has not reoccupied many parts of its original range, including former strongholds such as the Pribilof Islands, Bering Island, the Queen Charlotte Islands off British Columbia, Oregon, Mexico and most of California (Reeves et al. 1992); and reintroduced populations have not fared well (Nowak 1999). The species numbers about 17,000 off Russian coasts (Nowak 1999).
The Exxon Valdez oil spill in 1989 killed up to 10,000 otters in this center of their population in Prince William Sound, Alaska (See Aquatic Ecosystems chapter for more about this spill). Yet another unexpected threat is killing large numbers of Sea Otters off Alaska. In an ecological catastrophe caused indirectly by human activity, Sea Otters are now being preyed upon by Killer Whales (Orcinus orca). The latter animal has been deprived of its traditional prey in Alaska, Steller Sea Lions (Eumetopias jubatus), which have become endangered as a result of overfishing of their prime food supply--herring, pollock and ocean perch--by commercial fishing boats (Stevens 1999). Scientists began noticing the decline of Sea Otters in the early 1990s in the Aleutian Islands and western Alaska, a coastline stretching for 2,000 miles. Populations in some areas had declined by 50 percent, and by 1997, a survey found losses up to 90 percent (Stevens 1999). In one 500-mile stretch, Sea Otters had dropped from 53,000 in the 1970s to only 6,000 (Stevens 1999). The entire ecosystem has also been affected by the decline of Sea Otters. They are a keystone species, keeping kelp forests healthy by eating large numbers of sea urchins, which feed on kelp. Now large stretches of coast have lost their kelp beds, causing the entire ecosystem, from mussels to Bald Eagles, to decline (Stevens 1999). Other threats to Sea Otters include persecution by fishermen, shooting, oil and toxic chemical pollution, loss of food supply from overfishing, and ship traffic. The small population in Southern California has also been declining. In 1996, the Sea Otter was not listed in the IUCN Red List, but its sudden loss in numbers in Alaska and elsewhere in its range has again placed the species in danger of becoming extinct. The 2000 IUCN Red List of Threatened Species lists the Sea Otter as Endangered.
During the 1960s, otter fur became popular in the fur industry, causing an enormous decline in wild otters as trappers combed tropical rivers and wetlands for these vulnerable animals. The United States imported 45,000 otter skins per year from South America between 1965 and 1969, primarily from Brazil and Colombia, according to U.S. Department of Commerce statistics. All four of the Neotropical otters occurring from Mexico south to the southern tip of South America are now on Appendix I and have declined to threatened or endangered status from trapping.
The Giant Otter (Pteronura brasiliensis) is the largest of all otters, reaching almost 8 feet in length from its nose to the tip of its tail (Nowak 1999). Once common in river systems in Colombia, Venezuela, Guyana, French Guiana, eastern Ecuador, Peru, Brazil, Paraguay, Uruguay and northeastern Argentina, it has disappeared from most of its range and become extremely rare where it survives as a result of killing for the fur trade (Nowak 1999). These otters have been relatively easy to hunt because they live in large, friendly groups in feeder creeks and quiet, slow-moving rivers, denning in river banks. They vocalize to one another as they swim and gather on land, often in very loud chirps and barks. Thousands were killed, even after the species was protected by CITES Appendix I and hunting was banned throughout its range. When one otter is trapped or shot, others quickly come to its aid, becoming vulnerable to shooting; this seals the fate of entire groups of these beautiful animals. This trait of altruism is shared by other species of otters and has contributed to their elimination from entire areas. Trappers often set traps next to one another to take advantage of the extremely close ties between otters; one trapped otter might then bring others, which would become trapped as well. Pelts of Giant Otters were smuggled to European furriers in the 1980s, and this illegal trade has not been completely controlled by either exporting or importing countries. The Giant Otter is classified as Endangered on the 2000 IUCN Red List of Threatened Species.
The Southern Marine Otter (Lutra felina), a very rare species, is considered one of the most endangered of all otters. These very small otters, less than 4 feet long, are native to the cold coastal waters along the coasts of Peru and Chile; they have been hunted for centuries for their valuable pelts (Reeves et al. 1992). Darwin found them abundant in the Cape Horn and Tierra del Fuego region in 1830, but 130 years later they had been hunted to extinction in that region (Thornback and Jenkins 1982). Although now protected and listed on Appendix I of CITES, they continue to be hunted for their fur and persecuted by fishermen. In Chile, where the Marine Otter is highly valued for its pelt, The IUCN Mammal Red Data Book reported that the fur of this species is the most valuable of all otter fur, with hunting carried out from boats that cruise the coast for months at a time, killing any otters seen (Thornback and Jenkins 1982). On land, hunters with dogs chased them down and they were shot on sight, with pelts selling for up to $75 in the 1970s (Thornback and Jenkins 1982). Legal protection in Peru was accorded in 1977, before which a trapping season had been designated. The extent of illegal trade in South American otters is not known. Fishermen persecute Peru them for supposed damage caused to freshwater prawns, killing many (Mason and Macdonald 1986). There may be as few as 1,000 Marine Otters left in the wild (Nowak 1999), and they are listed as Endangered by the 2000 IUCN Red List of Threatened Species.
Trade in the late 1960s also affected the other two species native to the continent. The Southern River Otter (Lutra provocax) is listed as Endangered by the 2000 IUCN Red List of Threatened Species, an upgrade from Vulnerable in the 1996 version of the list. It has a limited range in Patagonia in Argentina and southern Chile. Having been eliminated from the majority of its range by trapping for fur, the Southern River Otter is now confined to remote and inaccessible areas in Argentina, such as national parks. The species has been reduced to small, isolated populations in south-central and southern Chile, where illegal hunting continues (Mason and Macdonald 1986). The Neotropical or Long-tailed Otter (Lutra longicauda) occurs from northwestern Mexico south to Uruguay. Both are CITES Appendix I species and listed as Endangered on the US Endangered Species Act; the 1996 IUCN Red Data Book omitted the Long-tailed Otter (Baillie and Groombridge 1996), while the 2000 version of the list classified it as Data Deficient. The Long-tailed Otter, in spite of its extensive distribution, is considered by some experts to be "severely depleted" in many parts of its range in South America. The majority of the 113,718 otter skins exported from Peru from 1959 to 1972 were of this species (Mason and Macdonald 1986). In the early 1970s, between 6,000 and 8,000 Long-tailed Otters were legally killed per year, with probably an equal number taken illegally (Mason and Macdonald 1986).
In 1973, Colombia banned the killing of otters, but poaching continued because otter pelts have a very high value; in Chile, for example, an otter skin is worth two or three months' wages to an unskilled worker. In spite of legal protection since 1924 in Chile, otters continue to be hunted with very little enforcement of the law (Mason and Macdonald 1986). During the 1960s and early 1970s, trade records did not differentiate between the four South American otter species. Since that period, all trade has been illegal, but in spite of CITES Appendix I listings, a large number of pelts of these species are exported to the fur markets of Germany and Italy, and others are sold locally in fur stores in Buenos Aires and other South American cities.
Otters of all species produce relatively few young, and have evolved with a low natural mortality rate. They are known to live to an average age of 15, and perhaps as long as 30 years (Nickerson 1984). Species with these traits, along with their large habitat requirements and protective behavior toward one another, are extremely vulnerable to extinction. Otters play an important role in aquatic ecosystems by taking slow and injured fish, thus preventing fish overpopulation, which results in undersized fish.