Blue Mountain elk study raises more questions

A three-year assessment of elk in Washington’s Blue Mountains produced unclear results, leaving wildlife managers contemplating further research and speculating about what may be happening.

The first year of the work showed just 13% of calves survived — a shockingly low number that led to calls for more liberal mountain lion hunting regulations. In 2022, managers and researchers from the Washington Department of Fish and Wildlife captured and fitted more than 100 newborn calves with tracking collars. Just nine survived. Predation was the leading cause of death and mountain lions were responsible for most of the predation.

But calf survival increased to 47.5% in 2023 and 52.5% in 2024. Across all three years, elk calf survival was measured at 36.8% — high enough to promote herd stability and possibly even growth.

A 2024 survey of the elk herd did show the population to be stable at around 4,000 animals. But the calf-to-cow ratio — a key measure of herd stability — remained low and did not align with the higher calf survival recorded in 2023 and 2024.

“It’s a little counterintuitive. It’s ‘What is going on?’ ” said Mark Vekasy, a wildlife biologist with the agency. “It’s possible that that was due to a little bit of a lag in production, because now that we did have survival the previous year, that calf cohort is too young to add to the productivity of the herd. So we’ve added some cows, but we haven’t increased productivity yet.”

The 2023 calves are old enough to produce calves this year and, so far, this winter has been relatively mild. That could result in higher calf-to-cow rations in the herd survey planned for later this spring.

“We’re very anxious to see if we’re finally going to see a response to better conditions in our cow-calf ratios,” he said.

The agency will pay close attention to those results and consider an expanded research project. The low calf-to-cow ratios — also known as recruitment — could be caused by low pregnancy rates or low cow survival. Future work would look at those and things like nutrition and body condition.

“It would be a cow-focused study, just looking at some of those very basic herd demographics to understand what’s going on,” he said.

The drought of 2022 was preceded by an overall decline in the Blue Mountain elk herd that started with a die-off during the severe winter of 2017 and another in 2019 when winter lingered well into what should have been mild spring conditions. Vekasy said the stress of those harsh winters, layered on top of the drought that followed, could have suppressed pregnancy rates.

Work from the Starkey Research Center in Oregon has shown habitat in the Blue Mountains can be limited, especially in the northern portion that extends into Washington.

“Nutrition is a little more limited here in a bad year. In an average year, it’s probably OK,” said Vekasy. “But if you put a bad year in there, or a few bad years back to back, then you have an issue.”

It’s also possible the terrible 13% calf survival rates in 2022 were caused by, or made worse by, environmental conditions that benefited predators. Vekasy noted the region was in a significant drought that year. Grass growth was stunted and offered very little cover. Nearly all the calves captured for collaring that year were found in shrub patches. In later years, more calves were found in grass.

“So it was a stark difference to us sitting and watching a slope (in 2023). You know, here’s a calf that stands up out of a patch of grass that you had no idea could even hide a calf. But the previous year they weren’t dropping calves on a slope, and if they did, you could see it from a mile and a half away.”

He also noted the work over the past three years was not a full-blown predation research project.

“We’re not saying that’s a complete picture of elk mortality throughout all the seasons,” he said. “We’re just saying that’s the survival for that cohort that we marked as neonate calves.”

The objective for the Blue Mountain elk herd is about 5,500. There have been some, including members of the Washington Fish and Wildlife Commission, who have suggested that since the objective hasn’t been met in several years, it may be too high.

Vekasy said there is a difference between carrying capacity and objective. He said the Blues can support a herd well above the objective. But when elk numbers are that high, they often leave the mountains and cause crop damage.

So prior to the die-off in the 2016-17 winter, the department allowed cow hunts in an effort to limit herd growth and reduce crop damage. Those hunts are mostly a thing of the past.

“That’s really the main reason why we weren’t getting to that herd objective in the past,” he said.

Barker may be contacted at ebarker@lmtribune.com.