POPULATION DYNAMICS OF A MARYLAND GRAY SQUIRREL POPULATION

Abstract

Gray squirrel (Sciurus carolinensis) population parameters were defined for a population in western Maryland. A cohort life table was developed based on mark and recapture data from the years 1976 to 1981. Spring litter size averaged 2.56 young while fall litter size averaged 2.76 young. For the study period, survivorship was Deevey type II (Krebs, 1978). Life expectancy at birth was 1.19 years. Net reproductive rate was 1.225 suggesting that the population was increasing. Population estimates using both the Lincoln-Peterson index and the Leslie matrix method agreed with the net reproductive rate. Population estimates by the Lincoln-Peterson index tripled in size between 1976 and 1980, then dropped in 1981. Leslie matrix population projections were consistently higher and did not decline in 1981. Hunting appeared to have no adverse effects on the population. Use of nest boxes appeared to increase the population. The results of this study are discussed with the proper management in Maryland.