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Mammals

Elk Calf

Rocky Mountain elk calf

Black bear, elk, and deer are among the most frequently observed mammals in the watershed. The diversity of mammal species has been only partially documented.

Overview

A total of 40 mammal species have been documented to occur within the watershed. Although no extensive surveys have been conducted for mammals in the watershed, it’s likely that most mammal species typical of the western Cascade Mountains and foothills are present. See a list of documented mammal species in the watershed (pdf).

Large Mammals

Black bear, elk, and black-tailed deer are commonly seen in the watershed. Elk and deer are usually found in open areas and in forests with abundant understory. Native Roosevelt elk (Cervus canadensis roosevelti) were almost eliminated from the Pacific Northwest in the early 20th century, but Rocky Mountain elk (C. canadensis nelsoni) were introduced sometime later. The elk in the watershed are mostly from Rocky Mountain elk bloodlines.

Elk numbers in the watershed have declined in the last 20 years. This is most likely due to the reduced availability of open habitat, as older clear-cut areas have matured into young forest and no new clear-cuts have been created since commercial timber harvest ended in the mid 1990s.

Less commonly seen are mountain goats, bobcat, river otter, beaver, and cougar. Mountain goats occur on the higher ridges and peaks. Bobcats are found throughout most of the watershed. River otter and beaver are, of course, typically found in stream or lake habitat. The Washington Department of Fish and Wildlife has an ongoing cougar tracking study, in which the animals are briefly captured and then fitted with radio transmitters. Tracking of the collared cougars indicates that they often have very wide ranges, and individuals commonly move in and out of the watershed.

Forest Carnivore Study

To learn more about the distribution of forest carnivores in the watershed, camera traps have been deployed in forested habitats since the summer of 2006.

The primary objective of the camera traps is to determine if fisher (Martes pennanti) and marten (Martes americana) are present. Both weasel-like animals are found in mature and old-growth coniferous forests in the Pacific Northwest, and fisher have become very rare in the region.

The motion sensor camera sites are baited with chicken carcasses and skunk-scented lure. Old-growth forest habitat at higher elevations is being targeted in the summer months, and forest adjacent to special habitats (wetlands, riparian corridors, and log piles) at lower elevations are targeted in the winter.

Though no fisher or marten have yet been captured by the cameras, other mammal and two bird species captured include:

  • black bear (Ursus americanus)
  • coyote (Canis latrans)
  • western spotted skunk (Spilogale gracilis)
  • striped skunk (Mephitis mephitis)
  • northern flying squirrel (Glaucomys sabrinus)
  • Virginia opossum (Didelphis virginiana)
  • elk (Cervus canadensis)
  • black-tail deer (Odocoileus hemionus)
  • red-tailed hawk (Buteo jamaicensis)
  • turkey vulture (Cathartes aura)

Fisher were last observed in the watershed in 1963. Marten have been documented recently near Snoqualmie Pass, about 4 miles from the eastern end of the watershed.

Another rare forest carnivore that potentially occurs in the watershed is the wolverine. In 2006, tracks identified as wolverine were observed in the snow by two skiers in the Alpine Lakes area about 6 miles north of the eastern end of the watershed.

For more information contact bill.richards@seattle.gov.