I have used website technology to test a model of the fall migration of broad-winged hawks from summer breeding grounds in northern North America to wintering sites in Central and South America. Anecdotal reports in the hawk migration literature suggest that broad-winged hawks maintain a constant rate of migration throughout their brief migration period. I created a migration itinerary (model) for the movement of broad-winged hawks along traditional migration routes from southeastern Canada and northeastern United States to Cardel Veracruz, Mexico. I then compared the wave-like pattern of peak migration through the United States predicted by the model with that observed across five observation sites along the route, all of which report their observations to the website: www.Birdsource/HawkWatch/Results. In general, the pattern of migration of broad-winged hawks predicted by my model was quite similar to the migration observed for this species during the fall of 1999.
Alissa Zimman, ’01 Green Bay, WI
Sponsor: Robert Black