SURVIVAL AND CAUSE-SPECIFIC MORTALITY-RATES OF ADULT BOBCATS (LYNX RUFUS)

We calculated survival and cause-specific mortality rates of 15 radio-marked bobcats in western Massachusetts during 1982-1985, and compared them to similar data collected elsewhere in the U.S. to assess their usefulness for population management. Annual survival of adult (greater than or equal to 1.0 years old) bobcats in Massachusetts (0.62) was similar to rates in other areas (0.56-0.67), excepting circumstances of high harvest rates (0.49) or very high poaching (0.19); there were no consistent trends in sex-specific survival. In many areas, sources of mortality other than legal trapping or hunting (e.g., poaching, starvation, disease, predation), may be substantial ((x) over bar = 53% of all deaths for studied populations) and should be incorporated into models of bobcat population change.