Photo by Jim Burns
Peregrine Falcon Management
The peregrine falcon suffered large population declines because of the post World War II use of the pesticide DDT. This pesticide decreased the female’s ability to release calcium to form eggs which significantly reduced reproduction rates. The peregrine falcon was placed under the protection of the Endangered Species Act in 1970, and the United States banned use of DDT in 1973. With the help of organizations like The Peregrine Fund, peregrine falcon populations rebounded to between 2,000 and 3,000 nesting pairs. In 1999, the U.S. Fish and Wildlife Service decided that the peregrine falcon no longer needed protection under the Endangered Species Act. However, to ensure that peregrine numbers continue to grow, the U.S. Fish and Wildlife Service will monitor the population every three years for 15 years.
The Arizona Game and Fish Department works with the U.S. Fish and Wildlife Service to conduct this monitoring. In Arizona, 60 sites were chosen statewide, with 20 occurring in each of the northern, central, and southern portions of the state. Using agency personnel and volunteers for monitoring, the Arizona Game and Fish Department reports occupancy, nest success, and productivity at these sites to the U.S. Fish and Wildlife Service. Information is collected from all of the other states to assess how the population is doing since removing it from the Endangered Species Act.