Idaho’s wolf population has dropped by about 13% during the last two summers, according to state wildlife managers.

The just-released 2023 estimate of wolves in the state is 1,150, down from 1,337 in 2022 and 1,543 in 2021, according to the state Department of Fish and Game.

Estimates from 2019 to 2021 ranged from 1,543 to 1,556.

A camera-based approach was used to calculate the state’s summer wolf population from 2019 to 2022. A new, genetics-based method produced the 2023 estimate, according to a department news release.

The new method uses genetic and age information taken from every harvested wolf checked by the department. Researchers use the genetic information to understand relatedness among harvested wolves as well as a computer modeling process that uses the pattern of relatedness to estimate the total number of wolves that produced that pattern.

The genetics-based method uses data that department staff have collected from harvested wolves for years. With the historical genetic data, researchers produced estimates for previous years.

Researchers worked for more than a year to produce the genetics-based estimates and then compared them to the camera-based estimates. The two methods produced similar results, according to the department.

“We recognize that the camera-based method is likely to become less reliable with a smaller wolf population,” Fish and Game Wildlife Bureau chief Shane Roberts said in the release. “Therefore, we’re planning to move forward with the new genetics-based method that will be more dependable at lower population sizes.”

“There’s really no way to check out and see what’s the truth and what isn’t” in terms of estimating the population, Phil Davis, a Cascade-area rancher, told Capital Press.

Nevertheless, the latest estimate remains well above department’s long-term target, Davis said.

He typically loses three to seven cattle a year due to wolves, and “we’ve already lost five this year,” he said. “One of my neighbors also lost five.”

“Idaho’s goal is to reduce the population as severely and as quickly as they can,” said Suzanne Asha Stone, director of the Idaho-based International Wildlife Coexistence Network. “We believe it’s dropping much faster than what they are admitting.”

The new methodology “is not peer reviewed, and so therefore it is not reliable,” she said. “We wish they had chosen a peer-reviewed method.”

Fish and Game will work with scientists to have the new method peer reviewed, “and we will continue to fine-tune it as we move ahead,” Roberts said in the release.

The summer estimate includes litters born in spring. Mortality from hunting, trapping and other causes occurs throughout fall and winter, often reducing the population by nearly half before the next breeding cycle, according to the department. The midpoint population — between the spring high and late winter low — averaged 1,270 between 2019 and 2021.

The legislature in 2021 substantially increased the allowed take and methods. The Fish and Game Commission in May 2023 approved a six-year plan to manage the population to fluctuate around an annual midpoint of about 500 animals.

The U.S. Fish and Wildlife Service reintroduced wolves in Idaho in 1995-96 with a goal of establishing at least 15 breeding pairs and 150 wolves before Endangered Species Act protections were removed and management transferred to the state. Idaho has managed wolves continuously since 2011.

Capturing and placing radio collars on wolves in nearly every pack provided the basis for early population estimates. Collared wolves were used to locate and count packs from the air.

As the number of wolves and packs grew and became more dispersed, it became unsustainable to maintain collared wolves in enough packs to estimate the population, according to the department. Hunters and trappers frequently harvested collared wolves, and capturing and collaring wolves became more difficult.