Climate change is altering the environment in profound ways. It is also undermining a basic component of wildlife management and forcing managers to address questions that could not have been imagined just a few decades ago. A recent paper on the future of polar bear conservation provides one example of this new reality, according to the Wildlife Management Institute.

The science and "art" of wildlife management traces its roots to the pioneering work of Aldo Leopold in the 1930's. Building on the foundation of ecological science, America's utilitarian culture, and a conservation ethic inspired by the likes of Theodore Roosevelt, Leopold and others framed wildlife management as a means to provide a "surplus" of animals available for use by people in sustainable ways. What has come to be known as the North American Model of Wildlife Conservation reflects how wildlife management evolved into a highly successful practice by the end of the last century.

Managing habitats, species and human activities to provide sustained yields of fish and wildlife for recreational, subsistence or commercial uses remains one of the main purposes of wildlife management. Underlying most of the theory and practice of wildlife management is the assumption that the environment is relatively stable or that inconstant elements, such as plant community succession, can be manipulated to create a desirable "status quo." For some species that demonstrate density-dependent population relationships with habitat, management is often designed to dampen fluctuations to create a relatively "stable state" with a predictable harvest.

However, the relative climatic stasis under which modern science and wildlife management developed is no longer part of the equation. Mounting evidence makes it clear that global temperatures are rising rapidly and the earth's climate is changing at an unprecedented rate. The consequences of climate change to the persistence of sea ice in the Arctic, to sea level, and to precipitation and plant ecology are increasingly apparent. This new reality has been reflected in ecological literature for several years, but it is now affecting the practical decisions wildlife managers face on a daily basis.

A recent article about the impact of rapid climate change on polar bear conservation serves as an example of the challenges climate change creates for wildlife managers. University of Alberta professor Dr. Andrew Derocher and 11 other polar bear scientists and managers evaluated the consequences of recent and projected changes in the timing of formation and persistence of sea ice cover on polar bear ecology. Among key findings are that the earlier melting of sea ice in spring, the delayed onset of ice formation in the fall, and the loss of multi-year ice over much of the Arctic will have profound impacts on polar bear distribution, food availability, reproduction and recruitment. The authors concluded that changes in arctic sea ice cover and more extreme climate variability could create conditions that exceed some polar bear subpopulations' ability to adapt within the foreseeable future.

A more immediate concern is that the reduction in multi-year ice and the longer ice-free period in summer are forcing more bears on shore without access to their primary food source, ice seals, for longer periods of time. In addition to causing nutritional stress that may affect reproduction and survival, these conditions are leading to more frequent contact between bears and people living and working along the arctic coastline. The increasing contact creates a serious public safety concern and elevated human-caused bear mortality through self-defense killing, management removal, and subsistence hunting.

The authors call for pre-planning, consultation and coordination of management responses to reduce risks to human safety and to optimize the potential to avoid extinction of polar bears. Diversionary and supplemental feeding, temporary confinement of shore-bound bears, and intentional population reduction are among the possible management responses evaluated by the authors. These measures are far from typical in most wildlife managers' tool box and would have seemed irrelevant as recently as twenty years ago. But the rapid loss of arctic sea ice is pushing both polar bears and polar bear managers onto new ground.

Climate change will continue to challenge, and may exceed, some species' ability to adapt to new conditions. It will also force wildlife managers to adopt new ways of dealing with increasing variability and unprecedented change in the systems entrusted to their care. (cs)