To prevent pneumonia die-off, Game and Fish inches toward bighorn ewe hunt in the Gros Ventre

JACKSON —The Wyoming Game and Fish Department is moving toward authorizing a ewe and lamb hunt in the Gros Ventre mountains near Jackson Hole, aiming to reduce numbers of the herd of bighorn sheep that live in the area.
The goal is to prevent a widespread pneumonia die-off, which typically happens when population numbers hit around 500 sheep.
Biologists counted 505 sheep in February, Game and Fish wildlife biologist Aly Courtemanch said. The population objective is 400 sheep.
“We would rather manage those numbers through hunting and allow hunters to harvest those animals rather than have them die from a pneumonia outbreak,” Jackson-area Game and Fish spokesman Mark Gocke told the Jackson Hole Daily.
The hunt isn’t yet official and still needs to be approved by the Wyoming Game and Fish Commission when it sets 2022 season regulations in April. 
But in February the department allowed hunters to apply for bighorn lamb and ewe tags in hunt area seven, which covers the Gros Ventre range and wilderness. The ewe and lamb hunt was proposed specifically in the Crystal Creek drainage, which the Jackson Herd calls home.
Gocke acknowledged that allowing hunters to apply for tags ahead of commissioners approving the hunt is a bit awkward.
But he said the department did so to balance the need to give hunters enough time to plan hunts — tag recipients are typically announced in May and hunts begin in late summer and early fall — with February animal counts, which inform the spring season setting process.
“You’ve got two separate processes going on and the timing just doesn’t jibe,” Gocke said.
The number of tags that will be proposed for Gros Ventre ewes and lambs is yet to be determined, pending review by the department’s regional wildlife supervisors. Those figures should be released around mid-March, Gocke said.
The Jackson Herd is distinct from the Teton Herd, which wildlife biologists and Grand Teton National Park officials are trying to protect.
The Teton Herd is smaller and does not face the same threat of pneumonia as the Jackson Herd. The Jackson Herd’s population numbers swing dramatically when disease sets in.
Game and Fish officials said they were interested in a ewe hunt during the department’s December bighorn sheep capture.
Fat stores in the Jackson Herd are declining, wildlife biologists said. 
Game and Fish and researchers at the University of Wyoming are hoping to study whether reducing the number of sheep — and, consequently, limiting the amount the herd’s members can compete with one another for food — would allow the herd’s body conditions to improve and prevent another pneumonia-driven die-off.
“The hypothesis is, if we can reduce numbers through hunting, we should see those sheep respond with better body conditions,” Courtemanch told the Jackson Hole News&Guide, the Jackson Hole Daily’s sister paper, in December. “That’ll be one of the first times, if not the first time, that’s ever been done.”
The last die-off in 2012 killed roughly 40% of the herd.

Gocke said the department is interested in allowing people to hunt both ewes and lambs because that’s how Game and Fish manages hunts for other species where female and juvenile animals can be difficult to distinguish. In seasons that involve antlerless deer, for example, the department will allow hunters to shoot either a doe or a fawn. In this case, the difference is ewe or lamb.
“It gives hunters flexibility in the field and it can be difficult to tell the difference,” Gocke said.
 
This story was published on March 5, 2022