A Beginner's Guide to Hawkwatching

Hawkwatching -A Challenge

A great drama in the sky will unfold this year, as it does every spring and fall. Though visible at untold sites across North America, it will be seen, enjoyed and care- fully recorded by only a few hundred volunteer observers. They are hawkwatchers.

This drama is the spectacle of our magnificent hawks, eagles, ospreys, falcons, kites and vultures in migration. These different species of hawk-like birds are familiarly called hawks. Twice each year many thousands of them make long and sometimes perilous journeys. Individuals of some species cross two continents, traveling from Canada to Peru and Argentina. In autumn they move southward to wintering grounds where food supplies are more reliable than in the frozen north. In spring they return to their northern nesting sites. Observers station themselves at selected vantage points, hoping to witness some of these flights.

Hawkwatchers find a special joy in watching some of our largest birds do what they do so superbly - fly! Those who watch also find great satisfaction in recording what they see, taking part in gathering information that might help unravel the mysteries surrounding these migratory flights.

Have you been missing this adventure? There are still opportunities for discovery. You could be the discoverer of new, useful information about how hawks fly over that .part of North America you know best - the vicinity of your home. Won't you join us?

When to Look for Hawk Flights

Fall is recommended as the most promising season for a new hawkwatcher to begin. Almost anywhere you are, you are likely to see more hawks in autumn than in spring. Only in Upper Michigan, northern Ohio, northwestern Pennsylvania and northwestern New York are more hawks seen in spring than fall. Fewer birds make the northbound journey because their numbers have been reduced by attrition on the wintering grounds and the hazards of migration.

The fall migration season extends from August to December. September, when most species are beginning migration, and October are the most active months. In the east, our Bald Eagles are on their way south by late August or early September, as are 3 species of falcons - American Kestrels, Merlins and Peregrine Falcons. Exciting big days at eastern lookouts and around the Great Lakes as far west as Minnesota occur the last 3 weeks in September with the pas- sage of the Broad winged Hawks, our most numerous eastern species. Flights of Sharp-shinned Hawks are seen during September and October. Flights of Cooper's Hawks, Ospreys and Northern Harriers also extend into October. The colder winds of late fall bring splendid Red-tailed and Red-shouldered Hawks in greater numbers. Add to that the thrill of an occasional Goshawk, or the grandeur of a Golden Eagle.

In Utah and Nevada, Golden Eagle flights may begin in August and continue through November. At San Francisco, Swainson's Hawks and Prairie Falcons are seen as early migrants with average dates in September. Look for the Ferruginous Hawk in October. Hawkwatchers in the west, where little study of hawk migration has been done, have wide-open opportunities to contribute significantly to our knowledge of western hawks.

In the spring, a watcher on the Texas border might see his first spring migrants in late January or February. In Maine or Canada the last spring migrant can arrive as late as July. In the east, mid- to late April brings your best chance to see northbound flights of the most species in the largest numbers. Whether hawks follow the same routes in spring that they use in fall is a question that amateur hawkwatchers (perhaps you!) might one day help to answer.

The Hawk Flights - Mystery and Majesty

Migrating hawks, we believe, follow flight paths that allow them to use the least energy. They tend to use prevailing northerly winds in fall and southerly winds in spring. In addition, hawks make excellent use of thermals, columns of warm air rising high above the ground. With scarcely a wing beat, a few hawks - or hundreds - might circle together in the warm air of a thermal, soaring up and up to a point where the thermal has dissipated. Then the hawks use the altitude gained to glide serenely away on a gradual descent that can easily cover a mile or two before the birds find another thermal to ride aloft. The hawks develop brisk speeds in these glides, as much as 40 mph.

Most species also use updrafts to good advantage. Updrafts are deflected air currents, created when wind strikes the side of a hill, mountain or other obstruction in the terrain. On the windward side of a long ridge on a breezy day, a bird might find sufficient 1ift to sail for many miles. Lee waves, also created by the air flow over mountains, are another means of lift. Sea breezes along our coastlines are used by hawks - opportunists all - to ease the migratory journey.

We believe that many migrating hawks converge along landmarks such as ridges, river valleys, lake shores and coast- lines. These features are "leading lines" that tend to draw the migrants into something like a "flight corridor." These concentrations of birds moving across the skies together provide a super-spectacle that can make even a casual observer a hawkwatcher for life.

When flight conditions along the leading lines become less favorable due to changes in weather and terrain, indications are that the hawks disperse widely. Where do they go? Do they just strike out across country, depending on thermal lifts here and there or other wind phenomena to boost them along?

Sometimes hawks have been observed backtracking, flying back in the general direction from which they came. We don't know why. Satisfactory answers have not yet been found for many questions about the habits and behavior of hawks in migration. Research will help us find ways to protect and preserve these beautiful birds; but that is only part of it. You may not be a scientist, but as a hawkwatcher you can contribute to our understanding of the ways of nature. How do topography and seasonal changes in weather affect hawk flights? You can become a 1ocal expert in these matters. The data you collect can be useful to scientists for years to come. You can have a stake in this research. We need more eyes watch1ng the sky in all parts of the country.

Becoming a Hawkwatcher

The best way to learn birds in the field, most people agree, is with the help of an experienced birder. Most veteran hawkwatchers enjoy sharing their knowledge with beginners, and will encourage you to get involved. They are a friendly group, eager to meet new people and talk about hawks.

A trip to an established lookout is well worth the effort. You can pick up tips on all aspects of the watch, get help with your hawk identifications and absorb the feel and excitement of what is going on. Even a day with few hawks sighted can be exhilarating.

But suppose you have no opportunity to visit an established lookout and must go it alone. Over much of the west and south you are likely to be a pioneer hawkwatcher. Try it! Every lookout in the country was discovered by someone!

Looking for a Lookout

Hawkwatching has been done from the tops of buildings, backyards, and office and sickroom windows. It can be tried anywhere. But you might start this way: Look over the topographic maps of your area and pick out any geographical feature within a reasonable distance of your home that might serve as a leading line. (Topographic maps may be ordered from Distribution Section, U. S. Geological Survey, 1200 So. Eads St., Arlington, VA 22202. or inquire at your local library.)

Now, along your leading line, look for a ridge, a rocky bluff, a river bed, a wind gap, a lake shore. A fire watch tower is a real find. When you have something promising in mind, drive out and have a look.

Think about the view. If it is less than 360 degrees, it should be wide open in the direction from which migrating hawks might be expected to appear. For example, in fall an eastern lookout might be best oriented toward the north and east; a western lookout toward the north and west.

Think about accessibility. The more difficult it is to get there, the less often you will go.

In uplands, your lookout should ideally be on a ridge, well-separated from other ridges and rising steeply from the valley below, its length oriented roughly in a north-south direction. In valleys or flat lands look for a wide view not obstructed by buildings or trees. In built-up areas, some productive lookouts are on the flat roofs of tall buildings. Whatever site you select, begin by getting any permissions that might be required for your use of the spot.

Choosing a Day

The best weather for finding hawks is probably on a day of good visibility with a pleasant, steady breeze (not heavy wind) from a northerly direction in fall, from the south in spring. However, migrating hawks, sometimes lots of them, will fly in almost any weather except a heavy downpour. The best hawkwatching conditions do not always conform to one standard. In autumn you are likely to see more hawks a day or two after a cold front has passed. The best flights in spring often coincide with warm air drifting from the south.

Try to select a day with blue skies, puffy white clouds and little or no haze. Clouds give the observer a depth of field and points of reference, making it easier to spot birds. But don't wait for optimal conditions to coincide with your free day. If the weather is reasonably decent and you have the time, by all means go hawkwatching!

Keeping Records

Record-keeping is a key part of hawkwatching. HMANA has developed a standard report form along with a set of instructions full of the information you will need. Study the instructions sheet, with a standard report form in front of you, for line-by-line guidance in completing the report. At first glance it may seem complicated, but it all smoothes out as you become familiar with the routine.

All of our knowledge of wildlife depends on field records carefully kept. Your records will help advance our understanding of hawks - and make you a participant, not a bystander, in the study of their migrations.

What to Take With You

Necessary items to take with you: watch, pocket notebook and pencils, field guide, thermometer, compass, binoculars. In addition to lunch and drinking water, some comfort items help sustain a longer watch if transporting them is not a problem - hat, extra jacket, sunscreen lotion, insect repellent, blanket, aluminum lawn chair, additional field guides.

The exposed situation of a hawkwatch lookout intensifies the effect of a hot sun or cold wind. Temperatures can vary 30 degrees or more between early morning and afternoon. Dressing in layers will prepare you to meet either chill or warmth.

Plan to bring a friend. Extra pairs of eyes are useful, so call on anyone who is willing to share the adventure and stay put for several hours.

Setting Up

Most often, more hawks are seen after the morning sun begins to warm the earth and create thermal activity. It is a good idea to arrive at your lookout early enough to settle in before the hawks start moving. Set your thermometer where it will be screened from the sun but air can circulate around it. Get your wind speed and direction and other data required by the report form. Write down the time. (If your watch is set to daylight time, subtract an hour for standard time.) Write down your weather data at the beginning of each hour.


Now! With your binoculars, scan the sky. Make sure that birds are not already slipping past behind you. Then you can concentrate more closely on watching that sector of the sky where you can reasonably expect your migrants to appear.

Here's a bird just above that long white cloud! It might come closer but you can't count on that, so work rapidly with what you can see.

Study the shape of the bird. Tail long or short? Wings long or short, round or pointed? Head prominent or small? Watch the manner of flight. Is it simply powering along in flapping flight? Kiting about? Sailing straight through on set wings, or circling to gain altitude? If it passes close enough, check plumage patterns of contrast, light or dark. Call out what you are observing as you see it. That allows any companions to compare views; and makes it easier to pick up the thread of recall when the excitement subsides.

As your first watch progresses, you will begin to under- stand that identification of hawks can be difficult. With experience, you will learn to start with a general feeling for the attitude of the bird in question. It is rather like recognizing an old friend or acquaintance a block or two away. But many times a passing hawk simply cannot be identified. So don't be hesitant to write down as unidentified the birds you can't call with confidence.


Scanning the sky with your binoculars is important. Face the direction from which you expect your hawks to appear. In early morning most hawks will be flying low, so pay more attention to the horizon. Later in the day, hawks may soar hundreds or even thousands of feet overhead. Scan from the horizon up, overhead, and then behind you.

The experts suggest that the hawks you are most likely to miss are those flying far out on either side of your flight line; or those so high they are in view only momentarily as they pass directly above you. To catch these, it pays to scan across your flight line from time to time. With your binoculars on distant focus, sweep slowly across the sky from your extreme left, to directly overhead, and on across to your extreme right. Horizon to horizon. This will require several sweeps each time. Your luck may surprise you.

Migrants vs. Local Hawks

At most lookouts resident birds are often seen wheeling about the area as they hunt. Sometimes a hawk will sail past just like a migrant, but if you keep watching you may well see it turn away from the line of flight, begin to hunt, or even head back the other way. Study these birds and you will soon become acquainted, and find your own answer to the question of how to tell migrating hawks from local birds.

Counting Large Numbers

Hawks! A parade of hawks. Here they come...

If the parade continues in stately procession across the sky, it will be a matter of identifying and counting. You can handle that. If the parade stalls, and the birds begin to kettle (i.e. , mill about in a slow whirlpool of hawks circling and gaining altitude) you may feel a sense of confusion adding to your excitement. How will you ever manage to count them?

First, try to get a quick estimate of the size of the problem. Is it a matter of a dozen or so birds? Or fifty, a hundred, several hundred, thousands? Watch the top of the kettle. If the flock is not huge, it will not be too difficult to count the birds after they reach the top of the thermal. Count them as they "peel off" to glide away in a smooth exit that will leave you breathless.

But suppose you are faced with an enormous throng of birds. You are on your own to give it your best effort! Some experts suggest that while the mass of birds is kettling you should try to estimate the number of hawks in just one sector of the circling mass -say a fourth or a sixth of the whole - to arrive at a rough approximation of the number of birds in the picture. But keep your eye on the top of the kettle. Be prepared to tick off the first birds gliding out of the therma1, perhaps streaming out several birds abreast. You wil1 be supremely busy for a while; but supremely triumphant when it is over. Exhausted, too.

That is the usual experience. But at times kettling hawks circle so high they are out of your sight before they peel off. Then you have only your estimate to work with. Be sure it is as accurate as possible and include in your notes a comment about what happened.

When a large number of hawks travel together in migration, the flocks are often of a single species, such as Broad-winged Hawks in the east or Swainson's Hawks in the west. But not all. A careful hawkwatcher will scan through each group with this in mind. Or, one person might count all the hawks while another identifies and counts only those hawks that are not the predominant species.

No Hawks?

It often happens that a hawkless morning is followed by a hawk-filled afternoon, or a blank day by a great one. If after a fair test you are convinced that your lookout is no good, then look for a better spot.

Remember, negative data is valuable and should be reported. You are the world's foremost authority on the hawkwatching spots you try. Your daily report should duly record that on this date, under weather conditions as described, no hawks were observed at your lookout.

Advantages of Membership

HMANA publications contain much valuable information that is not available elsewhere. All members receive the HMANA Newsletter twice each year, containing reviews of the spring and fall migration seasons and advice for sharpening your hawkwatching skills. Members are offered special prices on other HMANA publications (The Proceedings, The Journal) and beautiful art prints. All members receive the HMANA decal. HMANA maintains a collection of slides of hawks for rent to bird clubs and other groups.

We need the support of a growing membership to help us maintain our migration data collection and expand our educational services. We want you!

Eastern Massachusetts Hawk Watch, 2008
To contact EMHW, email
EMHW, PO Box 663, Newburyport, MA 01950
updated 07/20/2008