Important Bird Areas

Bear Creek Valley


The Bear Creek drainage is west of Denver and runs east from the head waters at Summit Lake atop Mount Evans to its juction with the South Platte River in Englewood. There is an 8,000 foot elevation change over approximately 35 miles. The Birds in the Balance study area includes the stream and a corridor 300 yards on either side of Bear Creek (approximately 12 square miles of habitat). Additionally, the drainage includes over 300 surface acres of water in three lakes. In the 8,000 foot change in elevation there are five life zones (plains to alpine) in a single, complete watershed. BIB has identified 13 monitoring sites that make up about 2500 acres of the 12 square mile Bear Creek corridor. In these sites the riparian and adjacent habitats have been categorized into 26 different types. State, county and municipal roads parallel or provide direct access to Bear Creek over at least 3/4 of the corridor.

Resources and History: Bear Creek has been used throughout the century. Residential and municipal park use were in place early on. Water diversion, impounding, and municipal use impact the Creek itself.

Ornithological Summary

This area provides a unique, exceptional opportunity to observe the landbird populations contained in a single, complete watershed. This includes bird seasonal movements up and down the riparian corridor through specific habitats. Informal observations have already indicated changes in populations and movement up and down the drainage with year to year seasonal variations in temperature and moisture. Two hundred twenty different bird species have been found in the corridor. Of these, 153 species, about 55%, are neotropical migrants. Observations have confirmed that 95 of the species breed in the Bear Creek corridor. Teams have observed 167 of the species in specific habitats and for levels of breeding and abundance during the migrating and breeding seasons.

Research and educational activities: Some plant communitites have been studied extensively such as around Summit Lake. Ptarmigan have been the subject of numerous studies.

See the IBA folder for a detailed, complete list of all species seen in the area through 1999.

Conservation Issues

heavy use, human access, habitat conversion, development

Efforts to address threats: Various groups and owners have made an effort over the last 10 years to imporve, develop, or manage habitat, trails, and access along the corridor. The Evergreen Park and Recreation District has developed/iproved the wetlands area at the inlet to Evergreen Lake. The Mt. Evans Wilderness area is currently being managed under a fee demonstration program. Plans include rebuilding more stable trails in the Summit Lake Park area where braided trail have severely damaged the surrounding tundra. Some other projects have included weed pulling, stream restoration, highway cleanup, and stream cleanup.