Siberian fur trade to overhunting. Instead of one sable pelt, the following was accepted as its equivalent: one fox, glutton (relative of the marten), or otter pelt; two blue-fox pelts; sixteen polar-fox pelts; or one hundred squirrel pelts. The Russian government decided the amount of other pelts that were equivalent to the sable pelt. Within forty years, almost all Siberian natives were forced into paying fur tribute to the Russians. Russian traders, hunters, and explorers reached the Pacific coastline by 1650 and were collecting fur tribute from most natives along the coast. Beyond the yasuk, the Russians had two principal ways of obtaining
American marten the population to increase, but deforestation is still a problem for the marten in much of its habitat. American marten are trapped for their fur in all but a few states and provinces where they occur. The highest annual take in North America was 272,000 animals in 1820. Trapping is a major source of American marten mortality in some populations and may account for up to 90% of all deaths in some areas. Overharvesting has contributed to local extirpations. Trapping may impact population density, sex ratios and age structure. Juveniles are more vulnerable to trapping than adults, and males are