SUBLETTE COUNTY – The Pinedale Anticline Project Office board met virtually earlier this month and wildlife updates shifted members’ focus – and dollars – from pygmy rabbits and prairie dogs to mule deer and pronghorn antelope.

Those at the annual meeting included Wyoming DEQ’s Nancy Vehr, Wyoming Ag Department’s Chris Wichmann, BLM’s Jason Gay, Sublette County Commissioner Sam White and Wyoming Game and Fish Pinedale Region’s John Lund.

PAPO manager Tracy Hoover, Sublette County Conservation District’s Mike Henn, Game and Fish biologist Ashleigh Rhea, BLM biologist Mark Thonoff and several citizens also attended.

Gay, standing in for chair Angi Bruce of Wyoming Game and Fish, reported for her that Game and Fish started the process to analyze designation of the Sublette Antelope Migration Corridor and is taking comments from stakeholders for the Wyoming Game and Fish Commission to consider before its March meeting planned in Pinedale.

“That the 30,000-foot view of that,” he said.

Each board member presented updates in their fields of expertise and the board conducted business along the way, mainly concerning the budget – salaries, an audit report and the 2024 calendar fiscal year.

Sublette mule deer

Rhea presented a summary for Sublette Mule Deer monitoring and mitigation in the previous year, noting significant declines of western Wyoming mule deer herds over several decades. Causes for these declines were divided among over-winter impacts of Pinedale Anticline energy development, low forage productivity due to limited habitat disturbance “and human-induced barriers to movement such as fencing not conducive to wildlife passage, highways and suburban residential developments, particularly within migration corridors and on winter ranges.”

Sublette mule deer suffered over the previous winter, Rhea said, with the worst result on the Pinedale Anticline’s west range with a mortality rate of 65 to 70 percent of monitored animals.

Last year, Game and Fish installed 35 GPS collars on does plus 17 more in March. From the dead ones, Game and Fish planned to reuse 16 collars, she said.

“Based on the GPS-collared deer, we were able to determine that adult survival was less than 65 percent in the northern portions of the Sublette Mule Deer Herd and expect fawn survival to be much lower,” she reported.

“Exceptionally severe winter conditions” brought on most of the deaths after the February flights,” and Game and Fish asked for more money to be added to its current PAPO grant agreement to maintain collars and discretionary surveys.

Sublette pronghorn

In the past, Rhea explained, PAPO has held “one pot” of money to split between the two species and Game and Fish was recommending more funds. Mule deer mortalities fluctuated more than pronghorn and she “anticipates” pronghorn losses will hit a mitigation trigger this year due to widespread starvation and disease outbreaks.

During February’s infrared flights, 3,220 antelope were counted in the survey area and 2,047 in the Anticline boundary, compared to the 2008 record of decision (ROD) baseline of 1,533. After 2022 hunting, the total population was estimated at 43,200 compared to 59,000 in 2009, she reported.

But after the infrared surveys, the Sublette pronghorn herd was “decimated” by starvation and disease on the Pinedale Anticline, with at least 75 percent mortality of GPS-collared pronghorn, Rhea said.

“The likelihood that a mitigation trigger for the PAPO pronghorn is met in 2024 is high,” she reported. Game and Fish recommended additional funding be added to the current grant agreement to GPS-collar 20 pronghorn females.

“We will see a 15-percent decline this year and years to come. It’s kind of harsh news.”

Game and Fish recommended continuing aerial infrared flights and close-up monitoring with an additional $180,000 for pronghorn and $241,000 for mule deer, a total of $4211,000 for the coming fiscal year.

Also, budgeted funds already set aside will be granted back to the accounts.

Eichmann asked if other Anticline reference sites “hit the trigger,” which is a formula in the ROD to determine if monitored wildlife declines are found in one or more sites, which would trigger additional mitigation.

Rhea said they plan to attach 20 more GPS pronghorn collars that show up during aerial flights. “If it’s a monitoring activity to benefit Sublette mule deer and pronghorn, we’ve been able to do that.”

Vehr moved to add to the current mule deer-pronghorn monitoring and mitigation balance so each species has $325,000 for a total of $650,000 for the next fiscal year; the board approved.

Pygmy rabbits

For pygmy rabbits, Rhea said the PAPO team reviewed consistent monitoring from 2011 to 2023 and only one year, 2019, “of the strong data set” showed a 15-percent decline in occupancy. She proposed the PAPO board consider the Game and Fish’s proposal to move monitoring to “a semi-regular basis rather than yearly.”

Game and Fish recommended moving to the Pinedale Anticline BLM record of decision (ROD) predetermined adaptive management for pygmy rabbits, she said.

PAPO team member Mike Henn asked Rhea to define “semi-regularly.”

“It’s up to the board,” she said. “Once every five years, or 10? Five years I think is perfectly acceptable.”

Vehr moved to accept the recommendation to monitor pygmy rabbits every five years; White seconded.

“How much savings would it provide to not (monitor) every year,” Wichmann asked.

Both pygmy rabbit and white-tailed prairie dog monitoring costs $135,000 a year, Rhea said.

Gay asked how this recommendation fit into the BLM’s 2008 adaptive management plan.

“You are allowed to change it within reason,” she said. “Depending on what you are seeing and based on how the BLM views adaptive management.”

BLM’s Thonoff said five years “probably allows us to encapsulate” pygmy rabbits’ status if it changes down the line and “keeps the intent of the ROD.”

Henn double-checked that the next monitoring will take place in 2028. The board voted “aye.”

Prairie dogs

Rhea said monitoring methods since 2009 for white-tailed prairie dogs “have been all over the board” but for the past three years, “consistent sampling” showed consistent and stable occupation in the Pinedale Anticline and reference areas.

There was no trigger of 15-percent decline over the past three years, she said. In fact, trends are stable or increasing numbers per hectare.

Game and Fish also recommended moving the animal’s monitoring to “semi-regularly” instead of yearly. She said she was “personally and professionally comfortable for a five-year timeframe.”

Thonoff agreed; he said at one time, each species cost $100,000 a year and now it’s down to $130,000 for both.”

Vehr moved to accept the recommendation and coincide prairie dog and pygmy rabbit monitoring reports every five years.

The PAPO board approved the motion.

The Pinedale Anticline Project Office board meets again in person in Pinedale in May, with dates to be determined. One topic on the agenda will be realigning salaries approved for the previous fiscal year to the calendar year.