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Bear reintroduction: lessons and challenges

INVITED PAPER 13th International Conference on Bear Research and Management BEAR REINTRODUCTION: LESSONS AND CHALLENGES JOSEPH D. CLARK, U.S. Geological Survey, Biological Resources Division, Southern Appalachian Field Laboratory, 274 Ellington Plant Sciences Building, University of Tennessee, Knoxville, TN 37996, USA, jclark1@utk.edu DJURO HUBER, Department of Biology, Veterinary Faculty, University of Zagreb, Heinzelova 55, 10000 Zagreb, Croatia, huber@vef.hr CHRISTOPHER SERVHEEN, U. S. Fish and Wildlife Service, University Hall, Room 309, University of Montana, Missoula, MT 59812, USA, grizz@selway.umt.edu Summary: Interest in translocating wild bears for the primary purpose of establishing sustainable populations (hereafter called reintroduction) has increased in recent years. Bear reintroduction, however, presents many challenges. Griffith et al. (1989) predicted that translocation success would be enhanced for a species if the number of founders is high, there is high genetic variability, the rate of population increase is high with low variance, the effect of intraspecific competition is low, there is low environmental variation, and there are refugia. Almost none of these criteria apply to bears. Also, homing behavior is strong and public acceptance may be poor. Nevertheless, because dispersal pressures on females are low, bears are generally poor colonizers ; translocation to establish satellite populations can be a worthwhile conservation strategy to facilitate this otherwise slow process. The most successful program was the reintroduction of 250 American black bears (Ursus americanus) from Minnesota to the Interior Highlands of Arkansas in the 1960s ; that population has grown to >3, 000 today. More recent efforts have involved fewer but better monitored animals and have sometimes employed techniques to improve site fidelity and survival. In Pennsylvania, female American black bears and their cubs were successfully translocated from winter dens, the premise being that the adult females would not return because of the presence of young cubs. That technique was compared to summer trapping and release in Tennessee and resulted in greater survival and reduced post-release movements. Small numbers of brown bears (Ursus arctos) have been reintroduced to the Cabinet-Yaak ecosystem in Montana and Idaho and also in Austria, France, and Italy to augment existing populations or to reestablish extirpated ones. In Europe, the efforts in Austria (1989-93) and France (1996-97) have already resulted in natural reproduction, and the young bears released in Italy in 1999 and 2000 may reproduce in the next year or two. The use of subadults, especially females, seems to limit homing. In many of the European programs, however, depredation by the released bears has been a significant problem. As with any small population, reintroduced populations are susceptible to environmental variation and stochastic demographic processes. Genetic drift and founder effects can be problematic, as well as inbreeding and outbreeding. Although reintroductions of other bear species are rare or have not occurred, such conservation strategies might prove beneficial in some instances. The use of captive bears from zoos, however, generally is not feasible except in extreme cases for some rare species (e.g., giant panda, Ailuropoda melanoleuca). Although managers have focused on the biological barriers to bear reintroduction (e.g., habitat evaluation, homing, low survival, monitoring and projecting growth, genetic issues), socio-political impediments to bear reintroduction are more difficult to overcome. Legal and procedural requirements (e.g., Endangered Species Act, National Environmental Policy Act) have caused lengthy delays that have threatened some programs. That notwithstanding, poor public acceptance and understanding of bears is the main reason some reintroduction programs have been derailed. Consequently, the public should be involved in the process from its initiation.

Bear; reintroduction; habituation

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