A study on annual mortality in the Moser River deer herd

A study to gain some insight on the annual gains and losses in a deer herd was conducted between May, 1966 and May, 1967 on a 37.3 square mile tract of land near Moser River in Halifax and Guysborough Counties, Nova Scotia. Weights, antler development and productivity data suggest the herd was in poor condition but that an improvement since 1961 had occurred. The relative importance of each mortality factor was estimated as follows: adult summer mortality six percent, legal kill 56 percent, cripple loss seven percent, predation five percent, late winter accidents four percent and winter loss 22 percent. The deer herd decreased between 1960 and 1964 and remained relatively constant between 1964 and 1966. A total of 12.4 hunters per square mile were recorded and the number of hunter trips per square mile was 21.6. Selectivity by the hunter was minimal. Peaks of hunting pressure were recorded during the first and fourth week of the 1966 season. A regression of kill per unit effort on cumulative kill to the start of each unit of effort for does and fawns was plotted and found to be significant at the 95 percent level of confidence. The snowshoe hare was shown to be the preferred food of the bobcat at Moser River and deer was important as food during certain seasons of the year, The average distance each cat moved during one night was 1.8 miles or a straight line distance of 1.2 miles. During the critical winter period 58 deer wintered in the Moser River concentration area. Femur fat content data suggest the fawns and adult males may be more vulnerable to winter mortality than adult does. Limited movement data suggest a migratory behavioral pattern between summer and winter range for some deer. A seasonal movement of 7.1 to 7.9 miles was recorded for one deer. Annual mortality was estimated at 51.0 percent and annual increment was estimated at 45.9 percent for 1966.