Last summer, Wyoming deer researcher Kevin Monteith and a handful of others wandered Wyoming’s southwest mountains in search of mule deer newborns.
They found 70 and placed a radio collar on each animal to monitor its survival. It was the second summer of what was supposed to be a three-year study that had shown, on average, a little more than a third of the fawns in the Wyoming Range Herd survive to their first birthdays.
This year they all died.
As a winter harsher than locals had seen in decades raged across the western part of the state, Monteith and his team waited while a pilot recorded one radio signal after another showing the fawns with collars were dead.
Fawns die during harsh winters. They don’t carry the fat reserves that adults store on their rumps and sides. They’re also smaller, requiring proportionally more energy to survive than their mothers, Monteith said. But rarely do almost 100 percent of the fawns die in a herd that numbers in the tens of thousands.
And worse, the does, the ones responsible for keeping herd numbers up and giving birth to one or two fawns a year, are also collapsing from exhaustion and starvation. Monteith estimated about 35 percent of the does have died, and more will likely follow.
“To date, I’ve handled more than 3,000 mule deer over many years and conditions, and I figured animals would be in bad shape, but I’ve never seen anything like this,” said Monteith, a professor at the University of Wyoming. “To see a whole segment of a population not have anything left is distressing and sad. Adult females are weighing like a bag of bones.”
The winter could be considered a crisis for a herd that draws hunters and wildlife viewers from across the country and even overseas. But for Wyoming biologists like Monteith, the die-off represented a unique opportunity rarely if ever afforded in wildlife research. Because research on deer in the Wyoming Range began a few years ago, the scientists will be able to answer several critical questions: What factors led to the die-off? What, if anything, can be done to bring them back? And could this, in the long run, actually benefit the herd?
“When things become severe enough that we see adult survival drop, you know things are bad,” Monteith said. “We have a once-in-a-lifetime or many lifetime opportunity to study the effects of a bad winter.”
Monteith began the Wyoming Range Mule Deer Project in 2013 as a spinoff of the larger Wyoming Range Mule Deer Initiative that started in 2010. Both efforts were attempts to understand why one of the largest herds in the state dropped from more than 50,000 to less than 30,000 animals in the early 1990s, and never really recovered.
Anecdotal blame fell on predators, energy development, overhunting, bad winters and not enough good food.
But over the course of the project some factors began to stand out.
The first phase of Monteith’s project looked at the impact of oil and gas development on the deer. Results showed what many suspected: deer generally avoid gas pads and are spooked by trucks and people, which meant as development flooded their winter ranges their useful habitat shrunk.
The second phase was then to parse out exactly what role environmental conditions such as drought, nutrition and predators play in fawn survival. Because without fawns, herds eventually wither and fade.
As a result, Monteith, graduate student Samantha Dwinnell, a team of technicians, and volunteers from sportsman’s groups such as the Muley Fanatic Foundation, have been gathering data on the Wyoming Range herd.
For people like Joshua Coursey, president and CEO of the Muley Fanatics, this winter is one more strike against a herd facing an increasing number of perils.
“It’s not just a bad winter, but disease and advancements in technology, long-range shooting and drones and aircraft,” he said. “There’s been so many critical things that have occurred that just keep hammering the resource, and a big blow like this puts it in a very critical state of recovery.”
Worst in 35 years
Just how bad was this winter for mule deer?
Worse than any that have been recorded in at least 35 years, said Gary Fralick, a wildlife biologist for the Wyoming Game and Fish Department who has spent the bulk of his career working with mule deer in and near the Wyoming Range.
Many older adults, including the now-famous mule deer named Jet who was being tracked by the Wyoming Migration Initiative, have died. More continue to perish. While this year’s youngest population blinked out, next year’s likely won’t fare much better since the does that do manage to survive and breed will likely have smaller, weaker fawns, Monteith said.
Will the herd recover?
Yes, agree Monteith, Fralick and Coursey. But how well and how long it takes is a puzzle they aim to solve.
“We noticed a 24 percent decline in fawns in the population from 1991 to 2012, and that is what we really need to understand,” Fralick said. “We know that the body condition of does is always playing a key role in that, and some other elements coming into play are (disease), and we know it is playing a role in the population, though to what degree yet we don’t understand, but we will.”
The Game and Fish Commission is trying to help by shortening the mule deer hunting season and offering fewer nonresident licenses. The decision was controversial — nonresidents support local economies and outfitters — but commissioners felt the herd needed help.
Winter ranges opened to the public on Monday for shed antler hunting, and Game and Fish asked people to stay away a little longer to reduce pressure on the already sensitive animals.
But after all of the gloom of shrunken numbers and dead deer, this winter provides not only an opportunity for study but also more food for the ones that survived, Monteith said. He hopes to increase the three-year fawn study to five years to better understand the long-term impacts.
“It will give us a very interesting glimpse into what this very highly valued deer population does, and apply it to the whole suite of deer herds we have in western Wyoming where we’re failing to hit objectives and scratching our heads on why they’re not growing,” he said. “Now we have the opportunity to see what happens when we have fewer mouths to feed.”
Ultimately, could the worst winter in decades actually turn into a positive? Maybe.
“In theory the animals should be fatter and stronger. There’s no way we can recover inching along the way we have the last decade,” Monteith said. “It’s quite possible we could rebound past where we have been. It’s definitely possible.”