Hawk Mountain Sanctuary

Hawk Migration Association
of North America

HawkWatch International



Bird Studies Canada



The Raptor Population Index (RPI) project represents a partnership between four leading hawk watch and migration research organizations: the Hawk Migration Association of North America (HMANA), Hawk Mountain Sanctuary (HMS), HawkWatch International (HWI), and Bird Studies Canada (BSC).

Accurate knowledge of population status and change is fundamental for bird conservation. Lack of reliable information on populations of many raptors forms a conspicuous gap in North American bird monitoring. The vision of the RPI partners is to contribute to effective conservation of migratory raptors through continent-wide long-term monitoring of raptor migration, scientifically sound assessments of population status, and public outreach and education.

The specific objectives of the Raptor Population Index (RPI) program are to:

  • Produce statistically defensible indices of annual abundance and trends for each species of migratory raptor from as many count sites as possible

  • Provide frequently updated assessments of the status of each species

  • Make these results widely available, i.e. to participating count sites, the scientific community, conservation agencies, and the public.



Support for the RPI project has been provided in part by generous challenge grants from the National Fish and Wildlife Foundation and the U.S. Fish and Wildlife Service, as well as by private donations from HMANA members and friends, and in-kind support from the three partner organizations, HMANA, Hawk Mountain Sanctuary, HawkWatch International, and Bird Studies Canada.