DISEASES IN A MOOSE POPULATION SUBJECTED TO LOW PREDATION

Abstract

Well-publicized studies on two moose diseases, elaphostrongylosis and moose wasting syndrome, conducted across Sweden from 1985 to 1994 resulted in an increased number of reports of sick and dead moose. A sample of 724 moose were investigated, including 426 females, 208 males, and 90 of unknown sex with an average age of 3.7 years (SD = 4.9, range 0-20). Prominent diagnoses were elaphostrongylosis (18%), moose wasting syndrome (11%), and accidental death (11%). Other important diagnoses were neoplasm (5%), parasitic (6%), nervous system (5%), infectious (4%), eye and ear diseases (4%), and predation (3%). From the beginning to the middle of the 20th century approximately 10 wolves, 130 bears, 175 lynx, and 100 wolverines were present in Sweden (449,000 km2). Currently, the scene is quite different with wolf, bear, lynx, and wolverine populations all increasing. The total number of large predators and scavengers is estimated at 2,500-3,000. We believe that the diversity of moose diseases seen in the future will differ from that observed during the 1980s and 1990s by being less visible due to increasing predation.