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Colorado conducting ambitious Front Range bald eagle survey

A four-year study was launched to determine population growth impacts on the bird.
Bald Eagle looking over Longmont
A bald eagle perched in a tree overlooking 3rd and Sumner in Longmont.


DENVER (AP) — Colorado has launched a four-year study of American bald eagles to determine how the protected raptors have adapted to population growth along the metropolitan Front Range and identify planning measures that could ensure the bird's future.

Colorado Parks and Wildlife says the study, involving biologists and volunteers from the U.S. Fish and Wildlife Service and the Bird Conservancy of the Rockies among others, will monitor nesting sites, food sources such as prairie dog colonies, reproduction and migration from the Denver area north to the Wyoming border.
Between 25 and 30 eagles are being fitted with transmitters using cellular communications networks to provide real-time data on eagle movements. 

CPW estimates there are more than 90 breeding pairs of bald eagles in the corridor. There were none at the end of the 1970s and only three in all of Colorado. That recovery — mirroring a nationwide trend — came after federal and state protections including banning the pesticide DDT.

The eagle's growth has coincided with rapid urban development. Denver's metropolitan area has nearly 3 million people, and CPW says nearly 750,000 additional people are projected to make the Front Range their home between 2019 and 2029.