异想天开的作文:英语高手帮忙翻译（3）

The northern fur seal, Callorbinus ursinus, is a cousin to eight other fur seal species found mainly in the Southern Hemisphere. Along with five types of sea lions-closely related animals with large bodies, coarser fur and more rounded snouts-this gregarious, harem-building marine predator belongs to the Otariidae family, thought to have diverged from a bearlike terrestrial ancestor about 25 million years ago. Unlike true seals, such as the harbor and ringed species, the Otariidae sport external ears and the ability to rotate hind flippers forward beneath their bodies so they can walk and climb on land. Females can live a quarter-century or more, while males rarely live beyond 16 or 17.
Like other herd-dwelling pinnipeds, fur seals follow a yearly cycle that begins in May when the 450-to 600-pound bulls return to the rookery to stake out prime breeding turf. The much smaller adult females return in June and usually within two days, give birth to a single 10-to 14-pound pup. Within a week, the adults mate. For nearly two months, the largest and most dominant bulls fight bloody, bellowing battles to defend their territories and keep other bulls away. During that time, the rookery takes on a complex structure that a researcher must carefully navigate in order to collect dead pups for study and to avoid the dangerous kings of the shore. By October, the pups begin to wean. About the same time, the seals start to scatter, with females, pups and juveniles migrating farthest, south of the Aleutian chain into the North Pacific.
Intelligent and at times aggressive, fur seals are agile on both sea and shore. But their most remarkable characteristic almost led to their demise: their dense waterproof underfur. The pursuit of this luxurious pelt by Russian and American traders in the 18th and 19th centuries twice pushed the seals to the edge of extinction. Between the early 1890s and 1909, an average of about 33,000 seals were killed each year in the Bering Sea, most of them females foraging for food. The U.S. commercial harvest alone (probably in excess of $200 million from the late 1860s to 1984) repaid Alaska’s $7.2 million purchase price 28 times over.
Then, almost a century ago, estimates that only 200,000 to 300,000 fur seals remained in the world mobilized conservationists and inspired the first international effort by governments to protect marine life. In 1911, the United States, Great Britain (acting for Canada), Japan and Russia signed the Treaty for the Preservation and Protection of Fur Seals and Sea Otters. It prohibited killing seals at sea except by Indians, Aleuts and other aborigines using primitive weapons. Congress halted all onshore hunting of seals on the Pribilof Islands between 1912 and 1917 except for subsistence hunting by local Natives. The animals rebounded at a tremendous rate, and the U.S. government reinstated an annual harvest on land, which ranged from about 34,890 seals in 1918 to 95,000 in 1941.