these localities. On the 21 counts made in the period 
1906-1936 not one eagle was reported, but on the 13 
counts made in the period 1936-1952 eagles were re- 
ported in increasing numbers in 77 per cent of these 
counts, 
Published Christmas census reports from the Iowa 
localities of Bettendorf, Davenport, and Dubuque also 
showed the same trend. The Bettendorf censuses, made 
by one man, covered 5 years (1917 and 1920-1923 in- 
clusive). Only one eagle was reported in this period. 
The Davenport census covered 12 years (1943-1955, 
except 1953); bald eagles were reported in 10 of these 
(83 per cent frequency). Bald eagles were largely re- 
sponsible for three of the four peaks in raptor popula- 
tions during this period. 
The Dubuque censuses, which covered 16 years 
(1939-1955, except 1942), indicate that the increase in 
eagle populations began in the 1940’s. Bald eagles 
were not reported in 1939 or 1940; for the remaining 14 
years, they were reported on 71 per centof these counts. 
Of four raptor peaks indicated in Dubuque censuses in 
the period 1944-1955, three were due to increases in 
numbers of bald eagles. 
Largest numbers reported on single Illinois counts: 
63 at Grafton, 1950; 46 at Moline, 1953. 
Marsh hawk, Circus cyaneus. The third most fre- 
quently encountered raptor in the Christmas census in 
Illinois, the frequency increasing from north to south. 
There is no indication of radical change in marsh hawk 
populations during the entire census period. Largest 
numbers reported on single counts: 22 at Grafton, 1953; 
22 at Bird Haven, 1951; 15 at Michael, 1944. 
Osprey, Pandion haliaetus. Recorded at three local- 
ities: 1 at Murphysboro, 1948; 1 at White Pines Forest 
State Park, 1953; 2 at Moline, 1955. 
Gyrfalcon, Falco rusticolus. Recorded at one local- 
ity: 1 at Arlington Heights, 1953. 
Peregrine falcon, Falco peregrinus. Single birds re- 
ported seven times in the [Illinois Christmas census: 
Springfield, 1934 and 1936; Havana, 1949; Chicago, 
1949; Moline, 1953; White Pines Forest State Park, 
1953; and Grafton, 1954. 
Pigeon hawk, Falco columbarius. Reported from eight 
localities: 1 each at Urbana, 1905; Ohio, 1922; Spring- 
field, 1939; Grafton, 1939; Chicago, 1952; Arlington 
Heights, 1953; Lisle, 1955; and 3 at Grafton, 1941. 
Sparrow hawk, Falco sparverius, fig. 2. This species 
and the red-tailed hawk were the raptors most frequently 
reported in the Illinois Christmas census. Frequency 
for the sparrow hawk increased from north to south. 
Largest number recorded ona count: 42 at Grafton, 1950. 
Barn owl, Tyto alba, fig. 15. The barn owl has been 
reported with slightly decreasing frequency from north 
to south. Largest number on single counts: 2 at several 
localities. 
Screech owl, Otus asio. The screech owl has been 
recorded in central, northern, and southern [llinois, in 
order of decreasing frequency. The figures may indicate 
merely that this species is most easily detected in the 
least heavily forested areas. The screech owl was the 
second most frequently reported owl, the barred owl 
first. Largest numbers reported on single counts: 6 at 
Michael, 1947; 7 at Paxton, 1928. 
Great horned owl, Bubo virginianus, fig. 18. The 
third most frequently reported owl, the great horned owl 
was reported most often in the more heavily wooded 
southern part of Illinois. Largest numbers recorded on 
single counts: 6 at Michael, 1947; 5 at Rockford, 1949. 
Snowy owl, Nyctea scandiaca. This northern species 
was reported from six localities: 1 at Lisle, 1937; 4 in 
the Chicago area, 1949; leach at Waukegan and Havana, 
1949; Moline, 1954; White Pines Forest State Park, 1955. 
Barred owl, Strix varia, fig. 21. This species was 
the most commonly recorded owl, with frequency in- 
creasing from north to south. In northern [llinois, the 
barred owl seemed to be less common than either the 
screech owl or the great horned owl. Though southern 
Illinois offers the most suitable habitat for both great 
horned and barred owls, the great horned owl appears 
to be more successful in the northern and the barred 
owl more successful in the central part of the state. 
Largest numbers of barred owls reported on single counts: 
8 at Moline, 1955; 7 at Murphysboro, 1951; 7 at Moline, 
1953. 
Great gray owl, Strix nebulosa. Only one record of 
the great gray owl: 2 at Moline, 1946. 
Long-eared owi, Asio otus, fig. 24. Reported in north- 
ern, southern, and central [llinois, in order of decreas- 
ing frequency, this species was seen with about the 
same frequency as the short-eared owl. Largest number 
reported on a count: 37 at Lisle, 1955. 
Short-eared owl, Asio flammeus. Reported with de- 
creasing frequency from north to south. Largest number 
reported on a count: 38 at Rockford, 1950. 
Saw-whet owl, Aegolius acadicus, fig. 1. Reported 
on 13 counts: 12 from northern and 1 from central [lli- 
nois. Largest number reported on a count; 2 at several 
localities. 
SUMMARY 
1.—Data on hawks and owls in Illinois, as reported 
in the Christmas counts sponsored by the National Au- 
dubon Society and its parent organizations, were ana- 
23 
