Editor's Choice - Challenges in Reintroducing Carnivores

June 2010 (Issue 47:3)
 

Devineau, O., Shenk, T., White, G., Doherty, P., Lukacs, P. & Kahn, R. (2010) Evaluating the lynx reintroduction programme in Colorado: patterns in mortality. Journal of Applied Ecology, 47, 524-531.

Large carnivores have suffered disproportionately as a consequence of human-caused habitat loss and fragmentation, direct persecution and other causes, and are amongst the most endangered taxonomic group as a result (Woodroffe & Ginsberg 2001; Safi & Pettorelli 2010). Large area requirements, wide ranging movements, conflicts with humans over livestock depredation and ungulate harvest all contribute to the challenge of maintaining carnivores in their native habitats. Carnivores are a priority for conservation because they have important ecosystem impacts and can be important umbrella species (Boutin 2005). Unfortunately, conservation options to recover or restore carnivore populationss are limited. Reductions in direct and indirect causes of mortality are ultimately the main recovery action. However, even if improvements are achieved, subsequently even wide ranging carnivores often cannot successfully access former potential habitat.

This is where reintroductions can play an important role in carnivore restoration. Given the increasing endangerment of many terrestrial carnivores, reintroduction has been planned or implemented for a variety of species. Many are familiar with the recent success story of the reintroduction of wolves Canis lupus to Yellowstone Park, U.S.A., and its potential ecological impacts (Smith, Peterson & Houston 2003). Reintroductions are being planned for a range of other species including Amur leopards Panthera pardus orientalis, grizzly bears Ursus arctos, swift fox Vulpes velox, Eurasian lynx Lynx lynx, and other species (Uphyrkina et al. 2002; Boyce & Waller, 2003). However, many planned reintroduction efforts have not taken place, or were not successful, leading to a bias in the reporting of the success rate of carnivore reintroduction. The recent success of the Yellowstone and Idaho wolf reintroductions may paint carnivore reintroduction in a more optimistic light than is realistic.

Reintroduction of lynx Lynx canadensis to the Colorado Plateau has been one of the largest carnivore reintroduction programmes worldwide. In this Issue’s Editors’ Choice, Devineau et al. (2010), present the first major results from this project to an international journal. Over a 7-year period, 218 wild-caught lynx were captured across extant populations in Canada, and their survival and cause of mortality was monitored after reintroduction to Colorado. The authors assess the success of this project through examination of survival rates and post-reintroduction dispersal of reintroduced lynx.

This paper was chosen as our Editor’s Choice for three main reasons. First, the Colorado lynx project has been amongst the most controversial carnivore reintroduction conducted. The challenges of reintroducing a northern species to the southern distribution of their range have raised important questions about whether conservation effort should be expended to restore endangered populations on range peripheries under negative effects of climate change (Steury & Murray 2004; Murray, Steury & Roth 2008). The Colorado lynx project, as a result, has been criticized for shovelling sand; pouring high numbers of lynx (218) into an area of poor habitat ‘quality’, when better use of conservation dollars could be achieved (Murray, Steury & Roth 2008). However, this study shows substantially higher survival in core reintroduction areas than expected, supporting the potential for the long-term success of this reintroduction.

Secondly, what is remarkable about this massive reintroduction effort is that after 7 years, over 47% of the reintroduced lynx had died, mostly from human causes. Approximately 30% of lynx were killed by humans on roads or through hunting. Importantly, 10% or so of lynx starved to death, similar to starvation levels in northern lynx in the Yukon, for example, during low phases of the snowshoe hare Lepus americanus cycle (Krebs, Boutin & Boonstra 2001), and suggestive of food limitation at their southern range limit. Cause of death was estimated from a sophisticated multistate mark-recapture model that accommodated the challenges of monitoring survival of dispersing lynx over a wide geographic range. This brings us to perhaps the most important conservation lesson of this lynx reintroduction, successful, or not.

Thirdly, this paper clearly illustrates the challenges of the spatial scale of carnivore ecology and behaviour that has not been well accommodated in recovery plans. Perhaps the most striking aspect is that reintroduced lynx dispersed over an area well over 1,000,000 km2 through Kansas, Iowa, New Mexico, Arizona, Nevada, Utah, Wyoming, South Dakota and Montana; truly an amazing geographic scale. Yet, we should not be surprised by the scales of lynx dynamics because recent studies demonstrate the continental scale connectivity of lynx populations through gene flow that is perhaps synchronized by large-scale climatic variability (Stenseth et al. 1999; Schwartz et al. 2002).

Therefore, while it may be premature to declare the Colorado lynx reintroduction a ‘success’, the study by Devineau et al. (2010) has demonstrated that lynx persistence at the southern extreme of their range will depend on human-caused mortality; on starvation that may interact with climate change effects on their major prey species, snowshoe hare; and that the spatial scale of lynx population recovery will probably require continued connectivity with populations to the north to sustain immigration during low survival periods (Murray, Steury & Roth 2008). Clearly, the next stages of the Colorado lynx reintroduction programme will be to examine the effects of these factors on reproduction, population growth, and then potentially, lynx population viability.

Mark Hebblewhite
mark.hebblewhite@umontana.edu
Wildlife Biology Program, College of Forestry and Conservation, University of Montana, Missoula, MT59812.

References

Boutin, S. (2005) Top carnivores and biodiversity conservation in the Boreal forest. Large carnivores and the conservation of biodiversity (eds J. C. Ray, K. H. Redford, R. S. Steneck & J. Berger), pp. 362 - 379. Island Press, Washintgon, DC, USA.

Boyce, M. S. & Waller, J. S. (2003) Grizzly Bears for the Bitterroot: Predicting Potential Abundance and Distribution. Wildlife Society Bulletin, 31, 670-683.

Devineau, O., Shenk, T., White, G., Doherty, P., Lukacs, P. & Kahn, R. (2010) Evaluating the lynx reintroduction programme in Colorado: patterns in mortality. Journal of Applied Ecology, 47, 524-531.

Krebs, C. J., Boutin, S. & Boonstra, R. (2001) Ecosystem dynamics of the boreal forest: the Kluane project. (eds.) Oxford University Press, Oxford, UK.

Murray, D. L., Steury, T. D. & Roth, J. D. (2008) Assessment of Canada lynx research and conservation needs in the southern range: Another kick at the cat. Journal of Wildlife Management, 72, 1463-1472.

Safi, K. & Pettorelli, N. (2010) Phylogenetic, spatial and environmental components of extinction risk in carnivores. Global Ecology and Biogeography, 19, 352-362.

Schwartz, M. K., Mills, L. S., McKelvey, K. S., Ruggiero, L. F. & Allendorf, F. W. (2002) DNA Reveals High Dispersal Synchronizing the Population Dynamics of Canada Lynx. Nature, 415, 520-522.

Smith, D. W., Peterson, R. O. & Houston, D. B. (2003) Yellowstone After Wolves. Bioscience, 53, 330-340.

Stenseth, N. C., Chan, K.-S., Tong, H., Boonstra, R., Boutin, S., Krebs, C. J., Post, E., O'Donoghue, M., Yoccoz, N. G., Forchhammer, M. C. & Hurrell, J. W. (1999) Common dynamic structure of Canada lynx populations within three climatic regions. Science, 285, 1071-1073.

Steury, T. D. & Murray, D. L. (2004) Modeling the reintroduction of lynx to the southern portion of its range. Biological Conservation, 117, 127-141.

Uphyrkina, O., Miquelle, D., Quigley, H., Driscoll, C. & O'Brien, S. J. (2002) Conservation Genetics of the Far Eastern Leopard (Panthera pardus orientalis). Journal of Heredity, 93, 303-311.

Woodroffe, R. & Ginsberg, J. R. (2001) Ranging behaviour and vulnerability to extinction in carnivores. Behaviour and Conservation (eds L. M. Gosling & W. J. Sutherland), pp. 125-140. Cambridge University Press, Cambridge.

Site Footer

• Privacy Policy
• Terms of Service
• Copyright
• Wiley.com