HawkWatch International Satellite Telemetry Study of Migratory Hawks and Eagles-Tracking Data Available On-line

Since initiating satellite telemetry studies in September 1999, HWI researchers have put backpack satellite transmitters on 32 migratory birds of prey. In September and October 2001, researchers put 17 satellite transmitters on migrant raptors in three distinct western flyways at migration study sites in New Mexico, Nevada, and Washington. Data from all 32 birds fitted with transmitters in 1999, 2000 and 2001 are available on-line at the HawkWatch website, www.hawkwatch.org.

HawkWatch International (HWI), based in Salt Lake City, Utah, is a conservation organization working to learn more about raptor populations and their migrations. In September and October 2001, researchers put 17 satellite transmitters on migrant raptors in three distinct western flyways at migration study sites in New Mexico, Nevada, and Washington. The addition of satellite telemetry to our migration studies allows more detailed delineation of migratory routes and stop-over points, helps to determine fidelity to migration flyways between seasons and years, and aids in more accurate matching of migration monitoring sites with specific nesting populations. The latter is critical information for interpreting population trends and identifying possible habitat conservation needs for these majestic birds.
The target species-Red-tailed Hawks, Northern Goshawks, and Golden Eagles-were selected for a number of reasons, including: abundance (red-taileds), recent concerns about negative population impacts related to widespread habitat alterations (eagles and goshawks), complicated movement patterns (all species), and the difficulty of adequately monitoring populations through conventional migration studies (all three species have a significant proportion of their population that is non-migratory). A final consideration was the size of the birds; the weight of the transmitter is a limiting factor and must not be more than 3% of the birds weight, so only a few raptor species are large enough to carry the units.
Since initiating satellite telemetry studies in September 1999, HWI researchers have put backpack satellite transmitters on 32 migratory birds of prey. The expansion of HWI satellite telemetry efforts to include new birds in 2001 was made possible by funding from the National Fish and Wildlife Foundation, M. J. Murdock Charitable Trust, Mr. George Perkins, Jr., the LaSalle Adams Fund, U.S. Bureau of Reclamation-Upper Colorado Region, and the JEPS Foundation.
Data from all 32 birds fitted with transmitters in 1999, 2000 and 2001 are available on-line at the HawkWatch website, www.hawkwatch.org. Visitors to the website can trace the movements of the tagged birds from their banding sites to their wintering grounds, through spring migration, and back to their breeding grounds in summer. This represents a rare opportunity for the public to witness science as it unfolds, exploring the wonder of migration by watching individual birds and their seasonal movements through western North America. Additionally, HWI is sharing Red-tailed Hawk migration data with Signals of Spring (www.signalsofspring.com <http://www.signalsofspring.com>) an educational site created by U. S. Satellite Laboratory, Inc. in partnership with a variety of research organizations to provide real-time data, resource materials, and curricula for classroom use. Data derived from transmitters deployed in 2001 has recently been updated through mid-January (as available).
HawkWatch International is a 501(c)(3) non-profit organization founded in 1986 to protect hawks, eagles, other birds of prey and their environment through research, education, and conservation.
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