October 3, 2022 at 2:38 p.m.
Natural Resources Board hears wolf number estimates showing healthy population
February hunt showed similar results to other hunt years
Natural Resources Board hears wolf number estimates showing healthy population
The scaled occupancy model is used by many agencies across the country for a variety of wildlife populations, Johnson said. It involves taking the total area occupied by a species, dividing that by the average territory size and then multiplying that number by the number of animals in the pack. Of course, the number of wolves per pack varies across the state, with larger packs farther north in the wolf range. An average pack size was used to complete the calculation. The average territory size per pack is 66 square miles, according to Johnson.
In addition to the scaled occupancy model, the DNR also has several radio collared wolves. The agency uses the collars to get a better understanding of wolf movements as well as territory size. This year there were 14 collars that were still providing data to the department, although there were many others in the field that had quit working for a variety of reasons. The department was able to collar nine more animals this year, however.
Another platform used to estimate wolf numbers is a citizen science project, which is somewhat unique to Wisconsin, Johnson said. Citizen science volunteers take a class on wolf tracking and are given an area to monitor where wolves are known to be present. Volunteers then monitor that area in the winter, when tracks are easiest to see. They are charged with not only reporting the presence or absence of tracks, but also how many animals appeared to be present at that time. This helps determine pack sizes as well as wolf range.
According to Johnson, almost 500 surveys were conducted last winter by volunteers by DNR staff, the United States Department of Agriculture (USDA) and tribal partners. These surveys were conducted over 17,000 square miles of known wolf range.
The results
Once the survey information was compiled, it was estimated there were between 1,193 and 812 wolves in the state. The model showed the most likely number to be 972, Johnson said. This represents a decline from last year's estimated population of 1,100. The number of packs estimated in the state remained approximately the same, but pack size did fall, according to the surveys. Last year's average pack size was 3.8 wolves. This year that number dropped to an estimated 3.2.
NRB member Bill Bruins brought up the timing of last year's wolf hunt, which started during the breeding season in February. The board "took a lot of heat" for holding that hunt, although it was statutorily required because the wolf was delisted during the hunting season, he noted.
"The board received a lot of criticisms for that. You're aware of that," he said. "One of the criticisms was the time of the year was going to decimate, you know, the reproduction process. There was one particular area where there was way more wolves harvested than in any other area. Did that are show a dramatic decrease in wolf numbers?
Johnson said the department had not completed a study in changes in occupancy relative to where harvest had taken place. Even in areas where there was concentrated harvest, there are still the same number of packs occupying the same territories, he reported.
He also said he did not believe it could be said that populations were "decimated" in those areas.
Overall, the controversial February hunt "most likely" had some reproductive impacts, but it would be difficult to say what those were, Johnson reported. Across the state, the wolf populations in Wisconsin remains healthy and biologically secure, he added, noting that he would caution against reading too much into a single data point, as the wolf population includes many different dynamics.
"A couple points," said board member Dr. Fred Prehn. "Most species that we manage through harvest are either pregnant, and/or just got pregnant such as whitetail. Walleyes in spring are spawning and they are harvested by the public. So, you keep talking that the pups are there. They would have been there in the fall. That whole argument can be discussed."
Biological and social carrying capacity
Prehn also spoke about biological and social carrying capacity of wolves in the state. He asked Johnson whether the model looked at carrying capacities. He also asked whether the department had looked at how the wolf range had changed over the years.
The model, Johnson said, was not made to judge carrying capacity. However, by looking at the wolf range, the number of packs and the number of animals in those packs, it would seem the state is approaching carrying capacity in wolf ranges. Social carrying capacity, he said, was "a whole new can of worms," but, with populations hanging near 1,000, it would seem that would be nearing the biological carrying capacity. Coming into 2020, growth rates were slowing, even in years where wolves were federally protected. This would indicate they may have been reaching their carrying capacity, he explained.
The quota
A discussion about the February wolf hunt would not be complete without bringing up the quota. Board chairman Greg Kazmierski was the first to mention that subject. The department came to the board before the hunt to say the biological quota, the number of wolves that could be harvested while still keeping wolf populations healthy within the state, was 200 animals.
Hunters harvested 218 animals in short order, which was reported as being grossly over the quota. At issue was the number of animal allotted to the tribes, in line with their treaty rights. Once the tribes took their allotment, the quota left for hunters in the state was 119. The tribes did not utilize their harvest, as it was known they would not, Kazmierski said. However, he said, if the biological quota was 200, then it was 200, not 119. This would mean hunters did not drastically over-harvest the species during that February hunt.
"I do want to clear some air," he said. "When you guys came to us with a quota for that February season, you came to this board with a quota of 200 wolves. That is what this board passed. But the media accounts of it were we overshot the quota by 100% and all that. The quota you brought to us was 200 wolves, correct? And we killed 218. I just wanted to clear the air on that."
"There is another component there, of course, of federal treaty rights that have to come into play," Johnson said.
"Right," Kazmierski said. "But that's not the quota. That's the harvest. The quota is the quota. That's how many you see the need to be harvested to manage the species, and that's where a lot of the confusion came in. We didn't overshoot the quota and that's the biological number that was recommended by the department to manage the wolf population."
Dr. Prehn said, if hunters were only to harvest 100 wolves, for instance, and the tribes did not exercise their rights to harvest, in order to manage the wolf population properly, the department would have to come back with an even higher number the following year, if a hunt were to be allowed, to keep wolf numbers in line. DNR secretary Preston Cole agreed that would likely have to be the case.
At present, wolves are once again included in the endangered species list. Any further wolf harvest seasons would be determined by that status, with a hunt being held only in the event that wolves once again come off of the endangered species list.
Beckie Gaskill may be reached via email at [email protected].
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