Chapter X.—Order Strigiformes: Owls (Family Tytonidas: 
Barn Owls) ; 
Barn Owl 
The number of young in broods of Tyto alba was found by F. N. 
Gallup (199) to average .2 in 87 cases at Escondido, Calif. The 
banding files record a nestling banded June 25, 1929, at Horsham, Pa., 
and captured while brooding eggs at Staten Island, N.Y., May 2, 
1930, less than 11 months later. In a British survey of 21) nests, 
the mean clutch was 3.8 eggs, 3.0 hatching and 2.8 young surviving | 
to leave the nest (Blaker 1933). Schifferli (199) reports that in 
Switzerland, egg clutches average about 5.4, broods about .6, and 
that mortality rates run 76 per cent for the first year of life 
(from time of banding) and 57 per cent per year for adults. 
Banding Work in North America 
Among 230 recoveries of both adult and nestling-banded 
birds, 92 originated in California, 2 in Ohio, 17 in Massachusetts, 
and 16 in Pennsylvania; the rest were scattered among 17 states. 
To obtain 143 recoveries of juvenile-banded barn owls, 48 banders 
ringed 901 birds. About 587 other barn owls (including juveniles) 
were also banded, but no recoveries on these birds were recorded. 
The principal banders were F. N. Gallup (279 banded 1926-1, 2) 
recoveries) and J. G. Peterson (109 banded, 1) recovered); both 
men worked in California. Among the recoveries of juvenile-banded 
birds were 9 found dead, hk shot, 19 captured, 11 caught in steel 
traps, 7 found injured, and 5 killed by autos. For 8, there was 
no recovery information. 
Characteristics of the Sample Studied 
Two nestlings were banded in January (Illinois and Texas), 
2 in March (California and Florida), in September, 5 in October, _ 
and 5 in November. Eighty-six per cent of the nestlings were ringed 
from April to July inclusive. To take advantage of the full sample, 
I started the life-table analyses for this species as of the date 
each bird was banded. In banding work with colonial species this 
would certainly be, poor technique (since dead birds found in colonies 
do not involve a random type of recovery); in noncolonial species, 
very few recoveries are reported immediately after the birds leave 
the nest (so that dating of this kind biases first-year recoveries 
in the opposite direction). In the barn owl bandings, this hiatus 
of reports was not evident (table 47), and I concluded that such 
dating of the barn owl year gives a reasonable set of workable 
data. 
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