SHOOTING AND COMPENSATORY MORTALITY IN TETRAONIDS

Despite the importance of compensatory mortality in setting harvest levels, few studies of tetraonids treat it directly. Total compensation for shooting mortality among adults in populations subjected to significant shooting (harvest rate over 5%) has been demonstrated only in Red Grouse Lagopus lagopus scoticus, and perhaps in Ruffed Grouse Bonasa umbellus. Only in Red Grouse is there direct evidence for total compensation for shooting in juveniles. Considerable indirect evidence for total or partial compensation comes from comparison of densities on shot and unshot areas, density dependent losses, normal sex ratios where only males are shot, and removal experiments showing that replacement birds exist in spring. The indirect evidence is weak owing to lack of control of immigration and doubt about the fate of "surplus" birds. Compensatory natality has rarely been detected in tetraonids.