Eye on the Sky: Derby Hill Hawk Migration (3/25/10 - 3/31/10)

Throughout the year, the eastern shore of Lake Ontario is a great destination for bird watching enthusiasts, due to its combination of unique habitat and positioning along major migratory routes for many species. Spring is a particularly exciting time to watch the skies along the shore, as this time of year brings the return of the raptors. Starting in March and continuing through May, a wide variety of birds of prey, including Bald Eagles, Red-tailed Hawks, Broad-winged Hawks and many others, can be seen making their way north along the eastern shore. When conditions are right, thousands of raptors can pass overhead in a single day. One of the best sites to view this spring migration is the Onondaga Audubon Association's Derby Hill Bird Observatory, located just south of the Salmon River near Mexico, New York.

A view from the bluff overlooking Lake Ontario at Derby Hill. Photo: Greg Chapman, Eastern Lake Ontario Dune and Salmon River Stewardship and Habitat Program

When conditions are right, numerous birdwatchers will converge upon Derby Hill to observe the spring hawk migration. I, Steward Greg Chapman, visited Derby Hill on March 27th, a sunny but cold Saturday morning, and joined a group of about ten birdwatchers keeping their eyes on the skies. It didn't take long before an impressive variety of birds were spotted--sometimes solitary, sometimes in groups--making their way overhead. Many were relatively common species seen this time of year such as Turkey Vultures, Red-tailed Hawks and Red-shouldered Hawks, which were seen in abundance, and several Bald Eagles were seen as well. Several less common species were also sighted during my brief visit, including a Northern Goshawk and an early Osprey--the second sighted this year (although these will become more common as the season progresses). What was really exciting for me, however, was a visit from a Golden Eagle, who came close enough for me to get a great look at through my binoculars. This was my first time seeing this large bird whose numbers have been increasing in recent years.

Jason Mauro of Syracuse, NY and Counter Seth Cutright (in red) look for hawks at Derby Hill Bird Observatory in Mexico, NY. Photo: Greg Chapman, Eastern Lake Ontario Dune and Salmon River Stewardship and Habitat Program

Derby Hill has been an important hawk-watching site for over 40 years--its elevated position along Lake Ontario's southeastern shore makes it the perfect spot to observe high-flying raptors heading north. These birds will not cross Lake Ontario during their migration, because they depend on currents of heated air rising off land heated by the sun, known as "thermals." Riding these thermals allows raptors to conserve energy during their long flight north. Derby Hill is one of a number of sites that keeps careful track of how many hawks are sighted each year--since 1979, a full-time counter has been employed by the Onondaga Audubon Society each spring to observe and tally the returning raptors. This spring, visitors to Derby Hill are likely to meet Seth Cutright, a Wisconsin native who is serving as this year's counter. The data he collects is entered into a database maintained by the Hawk Migration Association of North America (HMANA). The counts can be found online, with both monthly summaries for this year as well as daily reports, by clicking here.

Paul M. Roberts, in the foreground, Counter Seth Cutright, in red and other birdwatchers position themselves for the best view of migrating raptors. Photo: Greg Chapman, Eastern Lake Ontario Dune and Salmon River Stewardship and Habitat Program

The Derby Hill Bird Observatory is free and open to the public, and is located at 36 Grand View Ave in Mexico, NY. Directions can be found here. If you come, be sure to bring your binoculars. A helpful guide illustrating some of the important features of the many raptors that may be seen, as well as silhouettes that will help identify hawks flying high over head, is provided online by HMANA and can be found here. The number and variety of birds seen each day is dependent on a number of conditions; although some raptors will likely be seen most days throughout April that are free of rain and unusually cold weather, in general the best days to come are on warm, partly cloudy days with wind coming from the south. Mid to late April is truly the peak of the spring hawk migration season; some days may see thousands of raptors passing overhead, including many Broad-winged Hawks that often arrive in great numbers. For more information about Derby Hill and the spring hawk migration, visit the Derby Hill Bird Observatory website at http://www.derbyhill.org/.