Connecticut Audubon Society

AUTUMN’S MIGRATING RAPTORS
Milan G. Bull, Director, Connecticut Audubon Center at Fairfield

Only a serious striped-bass fisherman can appreciate the strength of the tidal flow as it ebbs across the submerged lower breakwater at Milford Point. Water pours down the Housatonic River, swings around the Point and over the flats before crossing the line of boulders with a quiet strength that goes without notice until you try to pull oars against it. With a friend on a fall day in 1963, I was pulling the oars in a leaky 15-foot lapstrake when unexpectedly, the tide won and washed us up on the bar at the elbow of the high breakwater.

Perched on a Volkswagen-sized boulder, directly above us, sat my first peregrine falcon, a big female. "Don’t move!" I hissed to my companion, but the words were scarcely out when the peregrine slipped off the rock and was away with the wind, up along the edge of the bars and off toward Charles Island, leaving a wake of panic-stricken gulls and shorebirds wheeling off in every direction.

I can’t recall how or even when we got home that day, but every minute detail of that magnificent bird is permanently etched in my memory. As well it should be. In those days, poisoned by DDT and other hard pesticides, all raptors were scarce, especially falcons. At that time, as far as I was concerned, peregrines were extinct, a picture in a field guide to fantasize about. Happily, that is no longer the case. Indeed, raptors (also known as birds of prey) almost did become extinct but with government intervention and the banning of hard pesticides, together with strict conservation regulations over the past three decades, these measures had near-miraculous results. A steady increase in raptor populations, together with a rise in public awareness about the importance of these birds in maintaining an ecological balance has netted many benefits for bird watchers.

We are currently enjoying the sighting of record numbers of hawks and falcons and along with them, increasing numbers of people who have formed national and regional hawk-watching groups such as the Hawk Migration Association of North America and the New England Hawk Watch. These groups, with the help of volunteers, organize "hawk watches" and collect all kinds of information about migrating hawks, including numbers, dates, species, migration routes and meteorological conditions. They have gathered an impressive amount of facts that have helped scientists learn more about these valuable birds. Connecticut has figured prominently in this research with a wealth of both migrating hawks and watchers who are well-organized far in advance of the early fall migration.

For example, in April 1998, The Connecticut Warbler published the impressive numbers of hawks migrating through Connecticut in 1997. From sixteen hawk watch locations scattered around the state and counted by volunteer watchers there were a total of 62,803 raptors. These numbers include 3 golden eagles, 160 bald eagles, 2,988 American kestrels, 3,284 osprey, 13,590 sharp-shinned hawks and 38,126 broad-winged hawks, among many others. Broad-winged hawks are one of the earliest and most common birds of prey migrating through Connecticut (great viewing of these birds during migration can be experienced at Deer Meadow located at Connecticut Audubon’s Larsen Sanctuary in Fairfield.) They constitute the bulk of the flights starting in September. They are the meat and potatoes of hawk watchers due to their plentiful numbers but many other species are recorded each year. Hawk watchers are treated to sightings of other birds of prey including ospreys, bald eagles, golden eagles, peregrine falcons, red-tailed hawks, red-shouldered hawks and small species like kestrel and sharp-shinned hawks among others.

The general pattern of hawk migration in Connecticut is from northeast to southwest with the majority of birds funneling though Fairfield County which ironically is the most populous area in the state and usually the best for hawk watching. The migratory pattern, however, is very much dependent on the weather conditions. The most experienced hawk watchers are never far from a weather report in September or October.

The best hawk flights almost always come after the in-season passage of a cold front and the brisk northwesterly winds that follow. The migrants use thermals, "bulges" or "pillows" of rising hot air to gain altitude by soaring, thus saving valuable energy that would be lost by flapping their wings. Dozens, sometimes hundreds, of hawks will use the same thermal, circling and rising together in a wheeling "kettle" of birds until the top of the thermal is reached. Then, one by one, they glide off southwesterly, sometimes streaming for miles, gradually loosing altitude - until the next thermal is reached and another kettle forms. This continues, weather permitting, until the final destination of Central or South America is reached. Strong northwest winds may push the migration down along the coast, while weak or southwest winds may scatter the birds well inland. Perhaps the best part about hawk watching is that it’s definitely a group event. The more eyes the better to scan the clouds and view their great migration southward.

Photo: Connecticut Audubon’s Birds of Prey Compound located at the CAS Center at Fairfield is home to several raptor species. These non-releaseable birds serve as wildlife ambassadors at Connecticut Audubon environmental classes. "Gypsy", a red-tailed hawk, is a veteran teaching assistant that resides at the compound. Photo by Eric Paradis.

Where to see Hawks
If you want to get out into the field and visit good hawk-watching sites during the fall migration, join the group that will almost assuredly assemble on any good day. There is hardly anywhere in Connecticut that doesn’t have at least some hawks migrating by in the fall, but there are at least three major areas that are especially good places to view these raptors. All are open to the visiting public.

Connecticut Audubon Larsen Sanctuary, Fairfield

Greenwich Audubon Sanctuary, Greenwich

Lighthouse Point Park, New Haven

You can also visit several facilities that care for injured Birds of Prey. It’s a wonderful experience to see these big, beautiful birds up close and to learn more about their importance in maintaining an ecological balance in nature.

Connecticut Audubon Birds of Prey Compound, Fairfield, CT (203)259-6305

The Raptor Trust, Millington, NJ (908)647-2353

Vermont Institute for Nature Studies VINS, Woodstock, VT (802)457-2779

About Hawks

The term "hawk" is used to describe the entire group of diurnal (active by day) predatory birds also known as birds of prey or raptors.
Worldwide there are approximately 270 species of these carnivorous birds. In Connecticut there are about 16 hawk species that regularly migrate to the state.
Basic similarities between all hawk species include keen eyesight (considered the best in the animal world - about eight times the visual acuity of humans), excellent hearing, hooked beaks and taloned feet. They are swift fliers with some hawks reaching 150 mph when diving for prey.
Size varies from the American kestrel weighing only 4 ounces to Bald Eagle that can weigh up to 13 pounds or more.
Most hawks pair for life but if a partner dies, a new mate is quickly found.
Strong allegiance to the breeding site, returning to the same nesting territory and the same mate each year.
Large hawks lay only one or two eggs each year and achieve maturity in around 11 weeks.
Small hawks lay from three to five eggs and grow to full size in one month.
All hawks are protect by state and federal laws. It is illegal to capture or kill hawks.

(Information obtained from "Hawk Facts" published by The Raptor Trust)