or nasal to genital contact, with copulation following shortly afterwards. This approach is more successful than the aggressive manner of the non-parous female, with mating taking place within 11 to 20 days after hibernation. The relationship between a sexually mature male and female Olympic marmot is polygynous; males tend to breed with three or four females in each mating season. Approximately four weeks after mating, the female gives birth to her young in a grass-lined burrow underground. Newborn pups cannot see, have no fur, and are pink in color. At first, the young exhibit no sexual dimorphism. It is about a month before the young Olympic marmots first leave the burrow; around the same time, they begin to be weaned. Even after they are allowed to emerge, the young initially stay within the immediate vicinity of the burrow, where they can be found chasing each other and wrestling playfully. Within a few weeks after first emerging from the burrow, the young are fully weaned and can feed themselves. Olympic marmots are not completely independent from their mothers until they reach two years of age. Breeding-age female marmots are extremely important to marmot populations. If a female of breeding age dies it can take years to replace her; marmots are usually limited to six pups in a litter, the maturation period is long, and many marmots die before reaching maturity. Interaction with humans The Olympic marmot is the second-rarest North American marmot, behind the critically endangered Vancouver Island marmot. Marmots were first sighted in the Olympic Peninsula in the 1880s. In the 1960s, David P. Barash conducted a three-year study of Olympic marmots after which he reported that there was an abundance of marmots in the mountains. In 1989, the total Olympic marmot population was calculated to be only about 2,000, but this low number was due to poor data collection. Other than this population census, little further research was done on the Olympic marmot until the late 1990s, when concerns arose about population status. Rangers and frequent visitors to the Olympic National Park had noticed that some populations of Olympic marmots had disappeared from their usual habitats. In response to this, the University of Michigan began a population study in 2002, in which the marmot population continued to decline by about 10% a year until 2006. Predation by coyotes that had not been present in the area before the 20th