Wednesday, June 20, 2007

Resilience of Bears Suggests Alaskans Should Consider New Management Options: Former ADFG Biologist

Former ADFG biologist Patrick Valkenburg writing in the Alaska Outdoor Council newsletter Outdoor Alaska says that Alaska bears are more resilient than previously believed, and more management possibilities exist than have been used in recent decades.

"In the past, many biologists have described bears; particularly grizzlies, as a “slowly reproducing” species that must be carefully managed to prevent overharvest, and have recommended restricting allowable harvests to 4 or 5 percent of population size, preferably mostly males. Despite abundant, sound data to the contrary, this “truism” about bears appears in print regularly, both in technical scientific articles and in the popular press. Many biologists are now beginning to realize that bears are not unlike other species and sustainable harvest rates are highly variable, can often exceed 15%, and depend on the abundance of bear food and immigration from surrounding areas. Hunted bear populations on the Alaska Peninsula and Unit 13 have been shown to be more productive than adjacent unhunted populations and sows in the hunted populations reproduce earlier, and have more cubs. Cub survival is generally also higher in hunted populations (cub mortality is primarily caused by adult males killing cubs). Thus, bear populations “compensate” for heavy hunting with better reproduction and higher cub survival."

Valkenburg suggests that while active management involving only wolf reduction has been effective in some areas, in other areas, bear numbers must also be substantially reduced to achieve similar results. He suggests black bear trapping - well accepted in areas of the USA East Coast - should be considered by Alaskans.

Read the entire article in Outdoor Alaska (PDF 2.6 mb)

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