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Mule deer, antelope predator projects focus on increasing doe/fawn ratios

by Wyoming Livestock Roundup

While USDA Undersecretary for Marketing and Regulatory Programs Ed Avalos was in Johnson County to view hands-on demonstrations of predator control, he was also updated on wildlife predation projects in other areas of Wyoming.
Wyoming Wildlife Services (WS) Southeast District Supervisor Craig Acres spoke on three projects, including the Shirley Mountain Mule Deer Project and the Big Creek Antelope Project in Carbon County and a Mule Deer Enhancement Project in Goshen County.
The Shirley Mountain Mule Deer Project began in 2008 and was recently completed.
“We very quickly went from a 65 percent doe/fawn ratio to almost 85 percent once predator control was issued,” said Acres.
Of the three projects, Acres said they’re the common types developed by local county predatory management districts.
“All these projects were done with existing personnel and with existing money within a budget,” he explained. “They’re incorporated into the human health and safety, wildlife and livestock protection duties, and they’re a good snapshot of typical game enhancement projects.”
Of the Shirley Mountain project, Acres said Mule Deer Herd Unit 540 had been below population objective since 1987.
“In recent years the post-season population estimates had been consistently below management objective, and the doe/fawn ratio had been 64 percent since 2004, so the criteria was met to initiate predator control,” noted Acres, adding that big game projects through predator boards and WS don’t address habitat issues, just the removal of predators.
“In 2008 we started to implement a coyote control project for mule deer in 540, which is east of the North Platte River and west of Highway 487, north of Hanna,” said Acres.
Two areas were split out, with coyote control in the southern area of 441 square miles and a control area to the north of 568 square miles, where WS only continued to remove coyotes to prevent calf depredation.
“We began enhanced coyote control in Spring 2008, and concluded operations in June 2010,” said Acres, noting that 1,697 man hours and 46 hours of aerial hunting were used to remove 546 coyotes.
Of the results, Acres said that the doe/fawn ratios in the control area in 2006/2007 were 56 percent, and 51 percent in the treatment area. By 2009 those ratios had overcome the 65 percent Wyoming Game and Fish Department (WGFD) threshold to instigate predator removal, so the project was concluded.
Acres said that, about five months after that determination, surveillance flights were made, and in June 2011 the WGFD reported a decrease in fawn ratios in the treatment area already.
“They requested to start the project again, but at this time, with the budgets in Carbon County, we’ll table that for now and see if we have the money and personnel to take it on later,” he said.
The ongoing Big Creek Antelope Enhancement Project in southern Carbon County, five miles from the town of Riverside, deals with a herd that meets the WGFD criteria of lower than a 65 percent doe/fawn ratio.
“This area is very sensitive due to minimal control taking place on these ranches in the past,” noted Acres. “That is important when we look at starting wildlife projects, because in a lot of the country the game animals have benefitted from livestock protection. This is an area where WS had not worked for up to eight years, giving us a clean slate where our results will not be skewed by prior activities. It’ll be interesting to see how this negotiates itself over the next couple years.”
The project just began with work on May 16, 2011, and so far 36 coyotes and two dens have been taken. Acres said work will continue through the summer until the antelope migrate out for the winter.
“When the antelope leave, the coyotes leave, and weather is the sole reason why they migrate,” he explained. “That area is 7,500 feet in elevation, and the first snows can be two to three feet deep.”
Acres said WS hopes to show appreciable results in the number of fawns that are raised.
“This project is a little different than Shirley Mountain, because, along with basic ground methods and aerial hunting, we’ll take plague and tularemia samples, along with GPS locations, stomach contents, and age and sex for each coyote that’s taken. We want to not just recruit more fawns, but also to collect a snapshot of coyotes in that habitat area,” said Acres. “We’ve already found a significant portion of coyotes have game animals in their stomachs.”
The Mule Deer Enhancement Project in Goshen County is taking place in the Goshen Hole Rim area, southeast of Wheatland along the Goshen/Platte county line.
“We were already doing livestock protection in the area, and removing coyotes on an annual basis, so we stepped up the amount of time we spend aerial hunting and on the ground, and we started keeping track of doe/fawn ratios,” explained Acres. “This new activity is coordinated with the time we spend on livestock protection activities, so we’re killing two coyotes with one stone.”
“We’re already there at certain times of the year when it’s important to protect calves, and the extra flights prior to mule deer and antelope fawning negate dens being born, and adults trying to feed their pups with mule deer and antelope fawns and calves,” he added.
WS is also documenting the data on coyotes taken in this study area.
“To this date, we’ve taken 100 coyotes in that area, and through last spring and early summer the stomach contents of 13.3 percent had mule deer fawns, and 26.7 percent had antelope fawns in their stomach,” said Acres. “As this project moves along, the percentage of those fawns in their stomachs will hopefully go down, because we’ll take the coyotes out before they’re born.”
Acres noted that the metabolism of a coyote allows it to digest food very quickly.
“We find a lot of coyotes with empty stomachs. If we come up with stomach contents with a viable amount of food matter, we know we’re there pretty quickly after they’ve taken that animal,” he said.
Acres said the Goshen County project needs to go another year before comparable figures will be gathered.
“The Goshen County Predator Management Board and WS plan to continue the project as long as funding continues, or until mule deer fawn recruitment reaches levels that constitute predator control need not be continued,” he stated.
Of predator management budgets statewide, Acres said, “I remember the year before the Animal Damage Management Board (ADMB) was founded, and I had six counties on their last six months of funding. With the advent of the state money, ADMB and the interest of Wool Growers and Stock Growers, along with the Wyoming Legislature, we were able to save six county programs quickly.”
“As a manager and a wildlife specialist, and someone who has a lot of interest in Wyoming succeeding as a state, even if this money goes away we will never go back to where we were,” he said. “Through this funding being available, we’ve proved what works and what didn’t work.”
“Even if we lose funding, we’ll never go back to six guys thumbing through brand receipts and trying to call research people trying to get projects to keep lambs and calves alive,” added Acres.
Christy Martinez is managing editor of the Wyoming Livestock Roundup and can be reached at

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