Extremely rare or accidental in the county; occasionally seen on or flying towards the mountains
December
Casual visitor at any season, but least likely in winter, most so in early spring; and possibly a few pairs nest
March - May
Resident; seen in the spring and fall migrations and year-round at Quabbin Resevoir
January - December
—H.L. Clark, 1887
Numbers declined seriously during the first two-thirds of the 20th century. Shooting was one major cause; even after the eagles were given full legal protection, they continued to decline, probably because of the effects of DDT and other persistent pesticides. Following the banning of DDT, numbers have been increasing gradually since the 1970s, with spectacular recoveries in some state.*