EMHW

When to Hawkwatch

The weeks when various species of hawks migrate through New England are quite predictable. The specific days when you are most likely to see them are less predictable and more weather dependent.

The largest hawk flights of the year are seen in mid-September, when the Broad-wing, ed Hawk and other common species funnel through our region. As many as 1000+ hawks can be seen in one day. Lower, but peak, numbers of the larger, less common hawks are seen in October and early November. In Spring, the majority of all hawks seen pass through the region from the second week of April to the second week of May.

The diagram shows by the thickness of its lines the relative size and timing of hawk migration through Massachusetts.

Where can you see good numbers of hawks? Most anywhere during the spring and fall peaks. Select any open site with a good view of the horizon in the direction the birds will be flying from: north/north-east in the fall or south/southwest in the spring. In the fall, the largest numbers of hawks move along a northeast-southwest axis across the state in a wide swath on either side of a line drawn from Newburyport to Springfield. The direction is reversed in the spring.

When should you hawkwatch? During peak periods, many hawks migrate by soaring on thermals, columns of warm air rising through cooler air. These conditions develop in the fall when a cold front passes through the area, producing cool temperatures, sunny skies, and a wind with a northerly component, from northwest to northeast. Movement may occur for several days after the winds shift to the north. In Spring, the best flights may be seen on the arrival of a warm front (southwest winds) or a cold front (northwest winds). Coastal sites in Massachusetts are most productive in spring, when the birds can be very close.

Hawks can migrate in any weather, so it may pay to hawkwatch under less than ideal conditions. (They tend not to fly in rain.) The best time of day to hawkwatch varies. Inland the best time is between 9 a.m. and 4 p.m. EST. On the coast, flights may start earlier in the day. When hawks are actually seen depends on where they are that day.

Beginning hawkwatchers may want to hawkwatch with more experienced observers, who can help them learn how to search for and identify migrants. There are many excellent locations to hawkwatch. You are more likely to find experienced hawk watchers at the sites described below. Wachusett Mountain in Princeton, is the best-known site and the busiest on weekends. Mt. Watatic (access by foot only) is a superb site, especially for ridge fliers, including accipiters and large Buteos in October and November. Bolton Flats, accessible by car, is excellent in September and Spring, and is not crowded. The Page School in West Newbury is accessible by car and good in spring and fall. Excellent coastal sites, best in spring, include Plum Island and Pilgrim Heights in North Truro.