Brood Size in the Barn Owl
Brood Size in the Barn Owl.-The accompanying tabulation summarizes the numbers of young of the Barn Owl (Tyto alba) that I have observed in 87 nests of this species at Escondido, San Diego County, California, from 1928 to 1946, inclusive. This record includes 12 fledglings that escaped before I could hand them.
Young in nest Frequency
1 3
2 9
3 11
4 28
5 18
6 14
7 4
The 366 young noted represent an average of 4.2 young per nest. In some years the annual mean was as high as 4.6 (10 nests in 1933) and as low as 3.3 (11 nests in 1934). If equally striking fluctuations were present in this region in other years, they were masked by the small size of the sample annually studied. I am indebted to Dr. J. J. Hickey for assistance in the analysis of data.-Fazn N. GALLUP, Escondido, Californin, February 5, 1949.
