There will be media stories, good comments, and ignorant angry comments, but here’s one from a person who knows-
Without commenting specifically on numbers or distribution of hunting quotas, I offer just these notes for your consideration.
Aldo Leopold; forester, wildlife ecologist, conservationist, father of game management in America, lived from 1887 to 1948. In 1944, he reviewed Young and Goldman’s Wolves of North America, which chronicled the extirpation of wolves. In his review, Leopold asked, “Are we really better off without wolves in the wilder parts of our forests and ranges?” He also asked, “Why, in the necessary process of extirpating wolves from the livestock ranges of Wyoming and Montana, were not some of the uninjured animals used to restock the Yellowstone?” Thirty years later, in 1974, the planning began, and in 1995, twenty years later, wolves were restored to Yellowstone.
Leopold’s thinking about deer, wolves, and forests is epitomized by his essay, “Thinking Like a Mountain.” In brief, he shot a wolf. In later years he came to “suspect that just as a deer herd lives in mortal fear of its wolves, so does a mountain (and its plants) live in mortal fear of its deer.” To deer, we could add elk. In Yellowstone, the lack of wolves led to woody species like willow and aspen being suppressed by elk browsing. With the return of wolves, willows are growing, once-rare birds are nesting in them, beavers are building dams from the willows, and the wolves are feeding a couple of dozen species of scavengers, including eagles and grizzly bears.
I’m far more concerned about disease than about predators on our large game.
Chronic wasting disease could wipe out our elk and deer. Wolves test elk and deer, looking for vulnerable animals all day, 365 days a year. You and I can’t do that. N. Thompson Hobbs (2006) evaluated the potential for selective predation by wolves to reduce or eradicate chronic wasting disease (CWD) in populations of elk in Rocky Mountain National Park. If it works, can we afford to throw away our only means of controlling CWD?
In Wisconsin, where Leopold lived, wolves were gone, and deer were overpopulated. Recently, tens of thousands of deer were killed to reduce their density, because Wisconsin had an outbreak of CWD. Adrian Wydeven, Wisconsin DNR mammalian ecologist, told me that where wolves live in Wisconsin, they have detected no cases of CWD. I’m reminded that Montana’s elk are 14% over objective, and Wyoming’s 34% over.
Wildlife Veterinarian Mark R. Johnson DVM (1992) wrote that “(W)ild canids may actually play a positive role in the disease ecology of brucellosis. By ingesting Brucella-infected material, especially during calving season, and excreting less bacteria than they eat, canids would reduce the amount of abortion of calving material capable of infecting other bison or elk.”
Paul C. Cross et al. (2010) suggest that high elk density and large group sizes are responsible for the spread of brucellosis. Wolves may help reduce group size and curb disease spread. “(T)he data suggest that enhanced elk-to-elk transmission in free-ranging populations may be occurring due to larger winter elk aggregations. Elk populations inside and outside of the GYE that traditionally did not maintain brucellosis may now be at risk due to recent population increases. In particular, some neighboring populations of Montana elk were 5–9 times larger in 2007 than in the 1970s, with some aggregations comparable to the Wyoming feeding-ground populations.”
Almberg et al. (In press), having surveyed canine distemper virus (CDV) in Yellowstone, write: “wolf managers in the region should expect periodic but unpredictable CDV-related population declines as often as every 2-5 years. Awareness and monitoring of such outbreaks will allow corresponding adjustments in management activities such as regulated public harvest…”
Diseases from domestic sheep have killed more bighorns than any predators have.
In 1981-82, a pinkeye (Chlamydia) epidemic took out more than half the bighorn sheep in northern Yellowstone. I’ve often wondered how that would have gone if wolves had found the first infected ram stumbling around blind. And by the way, it was the 1988 fires, not wolves, that doomed the moose population in the north part of Yellowstone.
As early as 1944, Adolph Murie realized that wolves selected weaker Dall sheep, “which may be of great importance to the sheep as a species.” In 1951, his brother, Olaus Murie, thought predators may have an important influence during severe winters in reducing elk herds too large for their winter range. In 1967, Douglas Pimlott pointed out that wolves control their own densities. Those observations remain cogent today. On Yellowstone’s northern range, interpack strife, starvation, and disease have reduced wolf numbers from 94 in 2007 to 34 this year.
Leopold had this to say about maintaining biodiversity: “The last word in ignorance is the man who says of an animal or plant: ‘What good is it?’ If the land mechanism as a whole is good, then every part is good, whether we understand it or not. If the biota, in the course of aeons, has built something we like but do not understand, then who but a fool would discard seemingly useless parts? To keep every cog and wheel is the first precaution of intelligent tinkering.” Hunting wolves is tinkering, Industrial Grade. I hope we can do it intelligently.
A major purpose stated in the Endangered Species Act of 1973 is “to provide a means whereby the ecosystems upon which endangered species…depend may be conserved.” But, according to several scientists (Bergstrom et al. 2009), Recent genetic studies have estimated that 380,000 gray wolves populated the western contiguous United States and Mexico before European settlement.” And northern Rocky Mountain (NRM) “wolves have been declared recovered with a population that is less than 1 percent of its original size, and with drastically depleted genetic diversity.”
Bergstrom et al. go on to say that, “Although 1600 wolves may possibly allow adequate connectivity and genetic exchange to sustain the metapopulation, the population numbers proposed under Idaho and Montana’s management plans do not. The best-case scenario is the loss of nearly half the population-a substantial population bottleneck. *** The unregulated harvests…will disrupt pack structure…” They analyzed population viability using harvest levels of 600 animals out of an approximate population size of 1500, and in 100 percent of their simulations, the population declined to extinction in less than 10 years.
Bergstrom et al. note that the NRM Distinct Population Segment (DPS) now has a density of about 5.5 wolves per 1000km2, although the density of wolves on Yelllowstone’s northern range reached 50 per 1000km2 in 2002. They cite Carroll et al. (2006), saying that a density of wolves similar to that of Minnesota’s proposed density of 18 wolves per 1000km2 across suitable habitat in the NRM DPS would equal a metapopulation exceeding 17,000.
They write, “The ESA’s stated purpose is ecosystem conservation, and evidence is plentiful that restoration of this once-extirpated keystone predator is effecting ecosystem recovery in the NRM DPS.”
Let’s let the wolves perform their keystone role in ecosystem recovery.
Norman A. Bishop
Bozeman, MT 59715
Almberg, E.S., P. C. Cross, and D. W. Smith. (In press) Persistence of canine distemper virus in the Greater Yellowstone Ecosystem’s carnivore community.
Bergstrom, B.J., S. Vignieri, S.R. Sheffield, W. Sechrest, and A.A. Carlson. 2009. The Northern Rocky Mountain Wolf Is Not Yet Recovered. BioScience 59(11):991-999.
Carroll, C., M.K. Phillips, C.A. Lopez-Gonzales, and N.H. Schumaker. 2006. Defining recovery goals and strategies for endangered species: The wolf as a case study. BioScience 56:25-37.
Cross, P.C., E. K. Cole, P. Dobson, W. H. Edwards, K. L. Hamlin, G. Luikart, A. D. Middleton, B. M. Scurlock, and P. J. White. 2010. Probable causes of increasing brucellosis in free-ranging elk of the Greater Yellowstone Ecosystem. Ecological Applications, 20(1): 278–288.
Hobbs, N. Thompson. 2006. A Model Analysis of Effects of Wolf Predation on Prevalence of Chronic Wasting Disease in Elk Populations of Rocky Mountain National Park. 9p.
Johnson, Mark R. 1992. The disease ecology of brucellosis and tuberculosis in potential relationship to Yellowstone wolf populations, Pp. 5-69 to 5-92 in Varley, J.D., and W.G. Brewster, eds. 1992. Wolves for Yellowstone? A Report to the United States Congress, Volume IV Research and Analysis. National Park Service, Yellowstone National Park, Wyo. 750 pp.