Tag Archives: justin dellinger

North-central Washington Mule Deer ‘Really Changing Their Home Ranges’ In Response To Wolves: UW Study

A University of Washington press release is fleshing out something I reported before last deer season:

Muleys and whitetails are beginning to change their behavior as wolf numbers increase in North-central Washington, and hunters might want to start looking in rougher country for the big-eared bounders.

A MULE DEER DOE AND FAWN CAPTURED ON A TRAIL CAM DURING A UNIVERSITY OF WASHINGTON WOLF-DEER STUDY. (UW)

“Overall, the researchers found that mule deer in gray wolf areas changed their behavior to avoid wolves altogether — mainly by moving to higher, steeper elevations, away from roads and toward brushy, rocky terrain,” states the news release that came out yesterday.

“Alternately, white-tailed deer that favor sprinting and early detection as ways to escape from predators were more likely to stick to their normal behavior in wolf areas, sprinting across open, gently rolling terrain with good visibility — including along roads,” it continues.

TWO WOLVES ROAM ACROSS A SNOWY EASTERN WASHINGTON LANDSCAPE. (UW)

That conclusion from the press release is based on field research involving collared deer and wolves and trail cams from 2013 through 2016 in areas of Okanogan and Ferry Counties occupied and unoccupied by packs.

“Mule deer faced with the threat of wolves are really changing their home ranges, on a large scale,” said UW School of Environmental and Forest Sciences associate professor Aaron Wirsing.

He is one of six UW, Oregon State University and other coauthors of an article recently published in the journal Oecologia recently.

He said that the species is moving uphill into less smooth territory “where wolves are less likely to hunt successfully.”

While the UW press release does note that that shift “could affect hunting opportunities” — “Indeed, some hunters in eastern Washington have already reported seeing mule deer higher on ridges where they are less accessible than in past years” — what it doesn’t mention is that that move just puts muleys closer to the jaws of another predator better adopted to stalking rough country.

Mountain lions.

A SCREEN GRAB FROM A VIDEO CAMERA SLUNG AROUND THE NECK OF A WHITETAIL DOE FOR THE UNIVERSITY OF WASHINGTON’S DEER-WOLF STUDY SHOWS A MOUNTAIN LION ATTACK. THE CAMERA WAS LATER RECOVERED AND ITS VIDEO POSTED TO NRA PUBS’ YOUTUBE CHANNEL.

One of the coauthors, Justin Dellinger, pointed that out when I spoke to him in the lead-up to 2018’s rifle buck hunt.

While the number of deer killed by wolves in the study was considerably fewer than how many cougars took –2 vs. 12 — he was quick to note that the data set is short, and it’s specific to North-central Washington and the early stages of wolf colonization.

Dellinger stated that the study occurred during relatively easy winters and theorized that in a severe one, mule deer driven down into open lowland winter range by snow could be preyed upon more heavily by wolves.

But there can be no doubt that even as deer adapt to the return of the long-legged lopers, they are still ending up on the menu.

Not far to the east of the study area, in similar though more densely forested country with fewer muleys and more whitetails, another UW researcher and his scat-sniffing dogs found that deer are the primary food source for wolves.

LAST YEAR A TRAIL CAMERA CAPTURED WHAT’S BELIEVED TO BE A SMACKOUT PACK YEARLING PACKING HINDQUARTERS OF A WHITETAIL FAWN BACK TO THE DEN IN NORTHEAST WASHINGTON. (JEFF FLOOD)

Earlier this winter, Dr. Samuel Wasser told Washington lawmakers, who funded his work, that they collected 8,456 piles of poo in northern Stevens and Pend Oreille County between April 2015 and June 2017, ran 6,095 through a lab and found that 826 had been left by 114 individual wolves.

As for what those packs were digesting, deer represented the largest portion of their diet, though moose weren’t far behind.

A PRESENTATION BY A UNIVERSITY OF WASHINGTON PROFESSOR BEFORE THE STATE LEGISLATURE SHOWS WHAT LAB ANALYSIS FOUND TO BE KEY PARTS OF THE DIET OF WOLVES IN NORTHEAST WASHINGTON. (DR. SAMUEL WASSER)

Deer also made up the plurality of cougar and coyote diets.

According to the UW press release, wolves will chase deer  “sometimes upwards of 6 miles.”

It postulates that whitetail hunting “likely won’t change to the same degree with the presence of wolves.”

It also says that the return of wolves to deer country “could affect other parts of the ecosystem,” likely meaning vegetation cover, “and perhaps reduce the number of deer-vehicle collisions.”

A heat map detailing where roadkill salvagers have picked up the most deer on state routes since July 2016 does show a number on Highways 20 and 21 in the area near where the wolf-deer study took place, but much higher concentrations in more populated areas where wolves are somewhat less likely to occur.

A MAP PREPARED FOR THE WASHINGTON FISH AND WILDLIFE COMMISSION EARLIER THIS WINTER SHOWS ROADKILL SALVAGE HOT SPOTS FOR BLACKTAIL, WHITETAIL AND MULE DEER ACROSS THE STATE. (WDFW)

The UW wolf-deer study was funded by the university, National Science Foundation, WDFW, Safari Club International Foundation and Conservation Northwest.

The Colville Tribes recently changed its wolf season for tribal members in areas that were part of the study — the reservation and the “North Half” — to year-round without a quota.

WDFW and UW researchers are also in year three of a five-year predator-prey study across the northern tier of Eastern Washington that should also bring new information about how wolves, deer, moose, elk, cougars, coyotes and other critters in the area’s wildlife guild are adapting to the changing dynamics.

How Are Wolves Affecting Washington Deer?

If your deer camp is anything like the one I belong to, the subject of wolves has probably come up since 2008.

That’s the year that Washington’s first known modern-day pack set up shop in the valley I’ve hunted since the 1990s and my dad and hunting partners before that. So I’ve been keenly interested in the wolf-deer studies being conducted there and elsewhere by state and university researchers.

RESEARCHERS LOOKING INTO WOLF-DEER INTERACTIONS IN NORTH-CENTRAL WASHINGTON ARE REPORTING INITIAL DETAILS ABOUT HOW WOLVES ARE AFFECTING ADULT MULE DEER AND WHITETAIL BEHAVIOR AND MORTALITY, BUT DID NOT STUDY FAWNS. EARLIER THIS YEAR A TRAIL CAMERA CAPTURED WHAT’S BELIEVED TO BE A SMACKOUT PACK YEARLING PACKING QUARTERS OF ONE BACK TO THE DEN. (JEFF FLOOD)

When he was a PhD. candidate at the University of Washington, Justin Dellinger placed small collar cameras around the necks of deer to determine their behavior as well as mortality inside and outside of wolf country.

Some initial findings are surprising – and amazing. One camera recorded the final moments of a cougar attack on a whitetail doe.

Dellinger, who has moved on to become California’s statewide large carnivore specialist, is pretty cautious about reading too deeply into them.

“I wouldn’t call anything I’ve done the definitive word,” he says.

But while wolves (and wolf people) drive me crazy, they’re here for the long haul, so being pragmatic I look for insights that deer hunters can use to possibly be more successful where they occur. I’m not going to let Canis lupus have the run of the woods.

DELLINGER’S RESEARCH OCCURRED in eastern Okanogan County and on the Colville Indian Reservation and involved mule deer and whitetails.

Frankly, I assumed that only the former species occupied the same sort of ground as wolves – mountainous national forestlands – but Dellinger’s hypothesis is that the long-legged predators’ territories actually overlap more with valley-loving whitetail.

“Wolves run – that’s how they catch their prey,” he states, and they can do that better in areas of rolling, gentle terrain than the “steep, rocky stuff” that mule deer prefer in this particular country.

But muleys and wolves do also occur on the same landscapes, and there the deer generally try to avoid contact with the wild canids because their defensive strategy – stotting off a short ways when confronted with danger – is easily defeated.

Thick, rough country “where wolves have to run around obstacles” works best for them, Dellinger says.

“They’re shifting to steeper, more rugged terrain,” he says of mule deer, “getting further away from Forest Service roads, which wolves use as travel corridors, and they’re using areas of more increased cover.”

That’s going to make it more difficult for some of us to hunt these deer, and anger and accusations that the herds have been decimated may follow.

A MULE DEER MOVES UP A STEEP OKANOGAN COUNTY SLOPE. (ANDY WALGAMOTT)

But as more and more wolves and packs occur in the state’s whitetail heartland, that deer species’ reaction is almost the polar opposite.

“They’re selecting for areas with greater visibility, away from cover and out in the open, areas of decreased slopes, closer to roads,” Dellinger says.

Those all help whitetails detect wolves early, allowing them to get a head start and “run like a bat out of hell,” he says.

That tactic didn’t work out for two study does, however, according to a recent Dellinger paper. It builds on previous research by Washington State University that pegged wolves as the “probable” reason why 137 deer died over the course of a two-summer study in much of the same region.

That work was based on collaring wolves and cattle, but Dellinger et al did the opposite, putting telemetry on 120 deer – bucks and does, whitetails and mule deer – in wolf and nonwolf areas.

When the devices gave out mortality signals they followed up and were able to determine the causes of death for 38 deer, with humans accounting for 16, cougars 12, coyotes seven, wolves two and bears one. Three others went down as unknown. Lions preferred does (10) while hunters went for bucks (13).

(DATA COURTESY JUSTIN DELLINGER ET AL)

It’s easy to overread the data as suggesting wolves don’t prey that much on muleys – packs don’t keep settling in the Kettle Range just to eat beef in summer, that’s for sure – but that doesn’t mean they’re not having other impacts on the species.

The big-eared bounders’ shift to more rugged terrain just puts them deeper into cougar country, Dellinger notes.

WHILE THE RESULTS are “really interesting,” Dellinger is quick to add that the data set is short and it’s specific to North-central Washington and the early stages of wolf colonization.

Another important caveat is that the research occurred during relatively easy winters. Dellinger theorizes that in a severe one, mule deer driven down into open lowland winter range by snow could be preyed upon more heavily by wolves.

“Wolf mortality could be additive and really impact deer populations” at that point, he says.

Also of note, no fawns were collared, so the impact wolves may be having on the most vulnerable part of the herd, and subsequent years’ adult buck and doe numbers, is unclear.

A December 2017 report by WDFW assessing Washington ungulate populations found none are being limited by wolves or other members of the state’s predator guild, though moose calf survival in central Stevens County, east of the deer study area, did elicit concern.

Bottom line: Dellinger says that a lot more research needs to be done to get a more complete picture of the interactions of wolves and deer here.

The state Department of Fish and Wildlife’s big five-year Predator-Prey Project in the Okanogan and Northeast Washington should really add to his work. It runs through 2021.