Thursday, June 21, 2012

Canada's wolves – How big and bad are they?

Wednesday, June 20, 2012 
To many people in rural areas of the West, bringing wolves back was a bad idea. To perhaps have brought back a possibly larger subspecies that was never here to begin with (the “Canadian” wolf) has added fuel to the controversy.
Pictures of very large wolves taken during the Idaho hunting season have appeared on the Internet, but some people suspect the photos have been digitally enhanced to make the wolves appear larger than they actually are.
So, what is the truth about these “Canadian” wolves? Are they really larger than the original wolf that used to roam the western states, and if so, how much larger are they?

Perhaps more importantly, if the introduced wolf is a larger subspecies, are they more likely to kill livestock and working dogs or to kill more deer and elk than the original subspecies?

Within the last several months, using newly available genetic information in addition to existing morphometric data, research biologists (Steven M. Chambers, Steven R. Fain, Bud Fazio, and Michael Amaral) with the US Fish and Wildlife Service completed an extensive review of wolves in North America – the third comprehensive review since 1944.

These researchers support the view that only three subspecies of wolves should be recognized in western North America and that a single subspecies (Canis lupus nubilus) inhabited all of the western states north of Arizona and New Mexico, and southern Alberta, southern British Columbia and Southeast Alaska.

The original common name for this relatively small wolf was “plains” wolf because it was first encountered by Europeans on the Great Plains. Although it was completely eliminated from the western United States by the late 1920s (except for a handful in the Cascades until the early 1940s), it continued to exist in healthy numbers in southwestern Canada and southeastern Alaska.

A considerably larger northwestern wolf (Canis lupus occidentalis) occupied northern Alberta, British Columbia, Yukon, and the rest of Alaska. This wolf has always been common and its distribution has never been appreciably affected by human activity. The northwestern wolf evolved in northeast Asia and Beringia during the Wisconsin Glaciation, while smaller subspecies of wolves developed south of the ice sheets.

The third subspecies of wolf in western North America, the Mexican wolf (Canis lupus baileyi), is the only subspecies that was ever truly endangered, having died out in the wild in Sonora in the 1970s. It is currently being reintroduced from captive animals into northern Arizona and New Mexico.

Unfortunately, biologists did not have good information on wolf genetics during the early 1990s when the decision was made to reintroduce wolves to Wyoming and Idaho from Alberta and British Columbia.

The concern at the time was that wolves for reintroduction should come from relatively abundant populations that had experience at hunting elk and bison, the two major prey species in Yellowstone National Park that were considered overly abundant.

Although there is a zone in southcentral British Columbia and southern Alberta where the two subspecies mix, the capture sites (Hinton, AB and Fort Saint John, BC) of the wolves transplanted to Wyoming and Idaho were well within the range of the larger, northern subspecies.

The Alaska Department of Fish and Game sent two pilots and two biologists to help with wolf capture and they were impressed by the large size of the wolves and their similarity to Alaskan wolves. The largest males weighed around 140 pounds.

The original wolf of the western states was 20-25% smaller, with large males seldom exceeding 110 pounds and the largest recorded being 125 pounds. The skull size of the northwestern wolf is also about 4-6% larger than that of the plains wolf. The evidence is pretty clear that the subspecies of wolf brought to the western states for reintroduction is not the same wolf that historically lived here.

Will this larger subspecies make a difference? Although it is generally true that larger predators tend to select larger species of prey, there is plenty of evidence that the original wolves made a good living hunting bison and elk and were often a serious problem for livestock as well, including the horses raised by Native Americans (for many examples see “The Wolves of North America” by Stanley P. Young and Edward A. Goldman, published in 1944).

No matter which subspecies of wolf had been reintroduced, managing livestock depredation problems would have required considerable money and effort, just as it did with the smaller plains wolf.
Fortunately for cattle ranchers, wolves seem to prefer elk more than domestic animals. The natural tendency for most wolves to hunt elk, and use of nonlethal conditioning methods combined with lethal removal of wolves that develop a pattern of killing livestock, should keep livestock depredation to a low and economically tolerable level.

However, it will be important for wolf advocates to be willing to compromise with ranchers on the issue of lethal wolf control because the interests of ranchers are critical, not only to successful wolf reintroduction, but to the conservation of habitat for many other species of wildlife as well.

The effects of the new, larger subspecies of wolf (or any subspecies for that matter) on populations of elk, deer, and other wildlife are more of an unknown and will likely be quite variable. All of the original ecosystems of the western states have been greatly modified by fencing, grazing, introduction of new species of plants, and by agriculture. In other words, it’s a whole new ballgame now, not just because of the larger wolf.

The amount of wolf predation on elk and other game species that people are willing to tolerate will be ultimately up to state legislators, governors, game commissioners, and voters. It is likely that wolf control programs, such as those conducted in Alaska, Idaho, Montana, and Wyoming, will be eventually implemented in other states as the range of the wolf continues to expand.

Pat Valkenburg is a certified wildlife biologist who worked for the Alaska Department of Fish and Game for 28 years on caribou, wolves, bears, and other wildlife. Since first retiring from ADF&G in 2003, he has continued to work on wildlife research projects in Alaska, Ontario, Manitoba, Labrador, and Oregon. He has spent the last two winters in the Enterprise area working with his wife Audrey Magoun, documenting the presence of wolverines in the Wallowa Mountains.

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