Two contrasting news stories about bears in the West were published on April 2, 2017. The first is a credible six-year scientific study of black bears by Colorado Parks and Wildlife. The second is a report from the Yellowstone Ecosystem subcommittee meeting of the Interagency Grizzly Bear Study Team in Jackson, Wyoming, featuring the head scientist spouting familiar political bullshit about too many grizzlies ever expanding their Yellowstone range.
The Colorado study documents rising temperatures, fewer days spent in the den, increased human conflicts, and dramatically decreasing female black bear populations in southwestern Colorado. Rising conflicts with bears eating human garbage does not mean the bear population is rising. Garbage, they conclude, is not addicting; bears go back to natural food when it is available. The key to bear populations is the carrying capacity: how much food is there, which is directly related to soil moisture and plant production that is, in turn, directly related to climate change and (by correlation) to drought and rising temperatures in the American West.
On the other hand, the Interagency Grizzly Bear Study Team in Yellowstone doesn’t believe climate change matters, writing in the Federal Register: “Therefore, we (The Fish and Wildlife Service) conclude that the effects of climate change do not constitute a threat to (the Yellowstone grizzly bear population) now, not are they anticipated to in the future.” Frank van Manen, head scientist of Study Team, says the grizzlies are expanding their range by 11 percent every couple years. Why? He says it’s because there are too many bears: “We are packing more sardines in the sardine can.” Van Manen thinks they are overflowing from the can into new territory where conflicts with livestock abound, and that today we are seeing the largest Yellowstone grizzly bear population size since listed as a threatened species in 1975.
This is bullshit. Climate change has already decimated key Yellowstone grizzly foods, especially whitebark pine nuts (which is now functionally extinct as a food source for bears), and has lowered the carrying capacity of the habitat through drought and rising temperatures (for a scientific discussion, click on the Grizzly-Sardine-Can link below).
Bears are ranging out of the Yellowstone core area, but it’s because there’s not enough food there. Hence, the density of grizzlies has decreased. The population of Yellowstone bears has not increased for 15 years and has probably declined since 2007—coincidentally the date of the tipping point for methane release in the Arctic, the commencement of abrupt climate change, and the sudden death of whitebark pine trees in Yellowstone. Is there any chance these events could be related? You bet your ass.