Document Type



Fox squirrel; Sciurus; reproductive chronology; reproductive activity; coccidiosis


This study was undertaken to increase the information available concerning the chronology of production in the fox squirrel (Sciurus niger rufiventer Geoffroy) and the contribution of spring and fall litters to the fall population. Previous reports indicated that two major periods of reproductive activity occurred annually. Our information indicates that only one major period of reproductive activity per year occurred in Iowa during 1966 and 1967. The onset of reproduction occurred in October when females in a state of oestrus were first handled. Parturition began in late December and early January. Young were born in all months from January through August, and 34 percent of all births occurred in March. Embryo, litter and placental scar counts indicated that the average number of young in litters of fox squirrels on the Iowa study area was 3.35. No significant difference was found between the number of young born per female during the period of spring parturition and the period of fall parturition. Coccidia spores were abundant in seven squirrels found dead between June 3 and July 4, 1966. Coccidiosis and mast shortage may have reduced the squirrel populations and resulted in compensatory breeding on the research area in 1966 and 1967.

Publication Date

October 1971

Journal Title

Proceedings of the Iowa Academy of Science





First Page


Last Page



©1971 Iowa Academy of Science, Inc.



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