FiGTjRE 1. — Bald-eagle abuudauce on 89 national wildlife refuges in the fall, winter, 

 and spring of 1953-54 compared with that of former years. The solid black dots 

 indicate an increase from estimates made in the 1940's ; the half -black dots, no 

 change; and the circles, a decrease. An outer circle indicates 10 or more eagles 

 reported. The greatest number was on the Upper Mississippi River "Wild Life and 

 Fish Eefuge, an extensive area reaching into the States of Minnesota, Wisconsin, 

 Illinois, and Iowa, where 300 bald eagles were reported in the winter of 1953-54. 



ary located on a principal flyway 

 for birds of prey in east-central 

 Pennsylvania, Dr. Maurice Broun 

 has recorded an appreciable in- 

 crease in the number of bald eagles 

 passing through in recent years. 

 Although the number noted has in- 

 creased appreciably at this point 

 during the past 20 years, part of 

 this may be the result of more ex- 

 tensive field observations. He states 

 (in correspondence) that the high 

 count of 142 eagles in 1950 was due 

 in large part to ideal flight condi- 

 tions — strong winds from the north- 

 west over a period of time. In 195?), 

 poor flight weather obtained and 

 only GO individuals were counted. 

 Of significance may be Dr. Broun's 

 observation that in the early 1980"s, 

 about 50 percent of the bald eagles 



passing through were immature 

 birds, while in recent years the fig- 

 ure remained consistently around 

 20 percent. This variation in the 

 proportion of yearling birds may be 

 indicative of a decrease in the east- 

 ern population of the liald eagle. 



Even in areas where the bald 

 eagle is only moderately abundant 

 there is a tendency for the birds to 

 gather at nightly roosts, and an ex- 

 aggerated idea of their numbers 

 often results locally. The senior 

 author (19o4) observed such a roost 

 near Stockton, Kans., in the early 

 thirties that was said to have been 

 occupied since the settlement of the 

 country. The first birds appeared 

 at this roost in November and the 

 last left in March. At one time. 



