Chestnut Ridge HawkWatch

Students at Hawkwatch by Katherine Dunn

Perched high above Interstate 684 rests an unlikely aerie—a platform for counting and identifying thousands of migrating raptors.

Each autumn from mid-August to November 20th, Bedford Audubon collects scientific data on raptor migration at the Chestnut Ridge Hawkwatch, located on an east-facing ridge at The Nature Conservancy’s 350-acre Arthur W. Butler Memorial Sanctuary in Bedford Corners, New York.

The Hawkwatch is nestled in the southern foothills of the Taconic Mountains, just 12 miles north of Long Island Sound. It offers spectacular views of the hills of Putnam County (New York) to the north; the towns of Bedford, Pound Ridge, and North Castle (New York) to the east; and Greenwich (Connecticut) and the Long Island Sound to the south.

The Sound acts as an invisible wall, forcing the migrating raptors into an inland bottleneck and directly over the Chestnut Ridge Hawkwatch. The raptors observed here migrate from their northern breeding grounds of Quebec, the Canadian Maritimes, and northern New England to their wintering grounds in the southern United States, and Central and South America.

The Chestnut Ridge Hawkwatch gradually grew from an informal gathering of hawk enthusiasts in the 1970s, to the construction of the first viewing platform in 1980 and the start of formal data collection in 1982, to the robust research and public program of today. We collect data on migrating raptors using protocols established by the Hawk Migration Association of North America.

Hawkwatch Vista by Katherine Dunn

Hawkwatch Vista by Katherine Dunn

Look by Katherine Dunn

Look by Katherine Dunn

Why Count Raptors?


The Hawkwatch data serves as an ecological litmus test that reflects changes in the health of our environment. Common birds, and raptors in particular, are indicators of the health of our ecosystem. Raptors  are near the top of the food chain, and are among the first in the animal kingdom to signal changes in the environment. Their presence is critical to alerting scientists to gathering dangers from pollution and degradation in the quality and quantity of habitat.


In the 1960s, scientists found steep declines in the populations of Peregrine Falcons, California Condors, and Bald Eagles were caused by the popular insecticide DDT, which was widely used for controlling mosquitoes and agricultural pests. Because of the impacts on raptors, we now know DDT is a persistent bio-accumulative toxin for many species, including humans. Its use is now banned in the United States.


The data collected at Chestnut Ridge and other Hawkwatches across the continent enables the Hawk Migration Association of North America, the Raptor Population Index, and other partners and researchers to produce reliable analyses of raptor population trends that drive conservation research and legislation across the country and all of North America. The data at our Watch and others can be found at HawkCount.


Partners in Research & Education

We partner with The Nature Conservancy to conduct the Hawkwatch at their Arthur W. Butler Sanctuary in Bedford Corners and Westmoreland Sanctuary to provide educational programming to the public.

Now in its fourth decade, our Naturalist Tait Johansson serves as the Site Coordinator, and we hire two seasonal research staff—a Lead Counter and an Interpreter and Spotter to carry out the annual four-month endeavor from mid-August to November 20 each year.

Hawkwatch Turkey Vulture by Anna Butler

Turkey Vulture by Anna Butler

If you’re interested in observing or volunteering at the Hawkwatch, please email: Tait Johansson.

Plan Your Visit to the Hawkwatch

The Chestnut Ridge Hawkwatch Platform is open to the public seven days a week August 15 to November 20th, from 9am to 5pm, weather permitting. One thousand visitors join us each autumn for the miracle of migration. Most years, in mid- to late- September we can get more than 1,000 migrating Broadwings, and just a few years ago we had more than 9,700 in a single day! The Hawkwatch staff is happy to help you spot and identify raptors and other migrating birds.

The most favorable weather conditions for hawk flights are autumn days with blue skies, puffy cumulus clouds, and northwest winds that follow a cold front out of the Great Lakes. Don’t be discouraged if these weather conditions don’t occur during your planned visit. West, northeast, and even south winds can produce a reasonable flight of hawks at Chestnut Ridge.

Migrant hawks don’t often pass through in a steady stream, so plan on spending a few hours at the Hawkwatch! Bring binoculars and a spotting scope, if you have them. A field guide is helpful, too.

Peak migration of common raptors at Chestnut Ridge
 Broad-winged Hawk  mid-September
 American Kestrel  mid-September to early October
 Osprey  late September to early October
Sharp-shinned Hawk  late September to early October
 Cooper’s Hawk  early to mid-October
 Red-shouldered Hawk  late October to early November
 Turkey Vulture  late October to early November
 Red-tailed Hawk  early to mid-November

Bedford Audubon hosts family-friendly programs and other special events throughout the season.

We welcome School, Scout, and other groups—for groups of 10 or more, please email to schedule your Hawkwatch field trip.

Directions to the Chestnut Ridge Hawkwatch

  1. Take I-684 to Exit 4 (Route 172). If you’re coming from the south you’ll make a left toward Mount Kisco; if you’re coming from the north you’ll make a right.
  2. Drive about 100 yards and make the first left onto Chestnut Ridge Road.
  3. Drive about 1.5 miles and look for The Nature Conservancy sign on the right.
  4. Continue across the bridge to the parking lot.
  5. Follow the orange trail south (immediately on the left as you drive into the lot) from the parking lot for a 10-minute walk to the platform.

Arthur W Butler Memorial Sanctuary