To count caribou in Alaska, wildlife biologists take aerial pictures of herds when they congregate in the summer, then blow up the photos and count individual caribou.
For moose, they fly over specific sampling areas, count each moose they see and extrapolate it over a larger areas of similar habitat to come up with a population estimate.
Counting wolves isn't quite so simple.
"A pack of six wolves can occupy a 500-square-mile area and on any given day you've got to figure out where they are in that 500-square-mile area," said the state's top wolf expert, wildlife biologist Mark McNay with the Alaska Department of Fish and Game in Fairbanks. "It takes a lot of airplane time to effectively count wolves."
And because airplane time isn't cheap and the state Department of Fish and Game's budget is as lean as most wolves these days, the state doesn't spend the time or money needed to count wolves in every nook and cranny of the state. In fact, the only parts of the state where biologists do intensive wolf surveys are areas where aerial wolf control has been approved or is being considered by the Alaska Board of Game. That amounts to about 3 percent of the state.
"In most of the areas where we don't have real good estimates there's no need to spend the money to get a real precise estimate," said McNay.
According to the Department of Fish and Game's last wolf population estimate compiled in 2002, there are between 7,660 and 11,170 wolves in Alaska.
While that may seem like a broad range, it's the best the state can do, given the enormity of Alaska, the resources the department has and how difficult it is to count wolves, said Division of Wildlife Conservation director Matt Robus, the state's game boss.
"That range is a result of a lot of different types of estimates from very good to ballpark estimations," he said.
But critics of Alaska's wolf-control efforts under hunter-friendly Gov. Frank Murkowski claim the state's wolf population suddenly increased when Murkowski, who has been a strong advocate of wolf control, took office in 2002.
According to Fish and Game statistics, however, that claim is bogus. Alaska's wolf population has essentially doubled in the past 20 years, according to the seven statewide estimates compiled between 1984 and 2002.
In 1984, the state's wolf population was estimated at between 4,481 to 6,136 and it has been climbing ever since.
The increase in wolves is likely due to an increase in the number of moose and caribou from the early 1980s to the mid-1990s, a time during which the state was actively conducting wolf control in several areas, said McNay.
"Ungulate populations around the state were increasing" said McNay, citing the Mulchatna and Fortymile caribou herds, as well as the Tanana Flats moose population, as three examples.
"Now things have kind of leveled out in some areas and are going the other way," he said.
Estimating Alaska's wolf population is not exact science. Biologists use a variety of sources to come up with a number of wolves in the areas they manage. They rely on information gleaned from trappers, hunters and pilots, as well as their own observations.
The department also uses sealing records from trappers and hunters to help estimate the number of wolves in an area. Every wolf that is trapped or shot in Alaska is required to be sealed by the agency. Hunters and trappers are asked on the sealing form to estimate how many wolves were in the pack they caught a wolf or wolves from.
"There are different levels of precision," said McNay. "In some cases it's a specific survey and in other cases it's a compilation of all these different types of data."
The fact the state relies on information provided by trappers and hunters to estimate Alaska's wolf population doesn't sit well with wolf worshippers.
"We believe that's like asking a logger if there's enough trees to cut down in a forest," said Karen Deatherage, the Alaska representative for Defenders of Wildlife, a group opposed to the killing of wolves in Alaska.
There are wolves spread over virtually all of mainland Alaska. The only places in the state without wolves are on Kodiak Island, the extreme Aleutian Islands and some islands in Southeast, said McNay.
"We don't have big areas without wolves," he said.
If you divide Alaska into 500-square mile units, the typical size of a wolf pack's territory, there is enough room for 1,000 wolf packs in the state, said McNay. At an average of seven to 10 wolves in a pack, that translates to 7,000 to 10,000 wolves.
"It actually fits nicely with the geography and distribution we know of wolves," he said.
The state's wolf estimate jives with Alaska's "ungulate biomass," according to McNay.
"If you have a certain number of wild ungulates, you can kind of predict what the wolf densities would be," McNay said.
In low-moose density areas, there might be a half dozen wolves per 1,000 square kilometers, McNay said. In high-moose density areas, there might be 15 or 20 wolves in the same 1,000-square kilometer area.
The highest wolf densities in the Interior are in Game Management Unit 20A south of Fairbanks, which consists of the Tanana Flats and Alaska Range foothills. That area is home to about 300 wolves. Not coincidentally, unit 20A boasts the Interior's highest moose densities.
"If you have more prey, you have more wolves," McNay said. "Your pack territories can be smaller; you can squeeze more packs into a smaller space because there's enough food to go around."
The department compiles a new statewide wolf estimate every three to five years but it serves more as ammunition for critics than it does a management tool for biologists, he said.
"When people send us e-mails and write us letters and call us to say, 'What are you people doing with wolves in Alaska?' we can put our program into context by saying this is the number of wolves we have and this is the number of wolves we're taking," said Robus. "It's not like we're taking 100 or 200 wolves a year out of a 500 animal pack."
Trappers and hunters kill an average of about 1,500 wolves a year in Alaska, which translates to 15 or 20 percent of the population. The annual harvest has remained constant for the past decade while the number of wolves in the state has continued to increase, an indication that Alaska's wolf population is "vibrant," said Robus.
The general biological rule of thumb is that a wolf population can sustain a 40 percent mortality rate and still recover because of the large number of pups they produce, he said.
"Even if you take the lower one of those (population) numbers (7,660) and you look at trapping harvest, hunting harvest and the number of animals taken in predator control programs, we are still way within sustainability," said Robus.
That's not the way wolf-control critics see it.
"They think wolves are like rabbits," said Joel Bennett, a former game board member who has been an outspoken opponent of the state's aerial wolf program. "They think with wolves you can make some mistakes and what's the big deal? We don't think that kind of thinking is responsible."
News-Miner staff writer Tim Mowry can be reached at 459-7587 or firstname.lastname@example.org .