Jackson Hole's big horn sheep population has been anything but stable. Officials say in 2011, 30 percent of the population was wiped out, and they say an unidentified bacteria may be to blame.
Early Sunday morning, the Wyoming Game and Fish Department began collecting biological samples from sheep at the National Elk Refuge in order to try and identify this bacteria.
They rounded up a total of six sheep using helicopters.
"They use a net-gunning technique where they fly over the animals and as an individual animal separates out from the rest of them they shoot a net out over the top of them. Then the animal gets entangled in that and they bring them here to us,” said Doug Brimeyer, a wildlife biologist with the Wyoming Game and Fish Department.
Once the sheep's safely on the ground, wildlife officials move in quickly and start gathering samples.
"We're taking tonsil swabs, nasal swabs. We're even checking for mites taking ear swabs. And then of course blood samples and fecal samples as well,” said Hank Edwards, a disease specialist with the Game and Fish Department.
Officials hope the samples will shed some light as to why pneumonia wiped out up to half of the herd in 2001, and another 30 percent ten years later.
"Our goal is to try and narrow down which pathogens are truly responsible for pneumonia in this herd,” said Edwards.
They also gave each sheep two sets of radio-equipped collars to help track their movements.
"We'll see where those animals spend their summers, how they're mixing with other subsets of the population, and then make assessments on how that disease can move between different areas,” said Brimeyer.
But even after the work they did today, it could still be some time before officials know what's truly killing these sheep.
"We'll start inoculating our culture plates and that process will continue for the next at least two weeks before we have any answers as to what might be going on,” said Edwards.
The state of Wyoming has agreed to share the data it collects with Montana and Colorado.