Twelve Quilomene bighorn sheep test negative for lethal bacteria

ELLENSBURG – This week’s tests showed no signs of the bacteria that causes pneumonia among members of the Quilomene bighorn sheep herd according to Washington Department of Fish and Wildlife (WDFW) biologists.

The department lethally removed and tested 12 bighorns from a remote area of the Ginkgo Petrified Forest State Park, where a domestic ewe infected with a pathogen known to cause pneumonia in bighorns was seen amongst them. The domestic ewe was lethally removed a week prior.

Wildlife biologists sent lungs and nasal swabs from nine bighorn rams and three ewes to the Washington State University (WSU) veterinary diagnostic laboratory to test for the presence of the bacteria. Tests from all 12 bighorns were negative.

“This is hopeful news for the Quilomene bighorn herd following their interaction with a domestic ewe this month,” said Mike Livingston, WDFW Region 3 Director. “We decided to lethally remove and test animals that were at the highest risk of being infected based on their proximity to the ewe. While these preliminary tests indicate good news, we are going to continue to take additional steps to monitor the herd.”

Beginning next week, WDFW will begin to conduct systematic searches of the area by helicopter to monitor the herd and may also capture and test animals opportunistically.

“Because of the severity of this disease to bighorn populations, we’re on high alert for any abnormal behavior in the Quilomene,” added Livingston. “And, if we’re able to capture and test a few animals, that may bolster additional confidence in these negative results.”

WDFW encourages anyone who observes bighorn sheep within the vicinity of the park that are coughing or displaying other abnormal behaviors to contact the department immediately.

Earlier this month, wildlife biologists were notified that an off-duty Kittitas County Sheriff’s deputy had observed a domestic ewe with seven bighorn rams in a remote area of the park. Wildlife biologists removed the animal, and subsequent testing at WSU confirmed she was a carrier of the Mycoplasma bacteria, which causes fatal pneumonia in bighorn sheep.

Pneumonia caused by the bacteria, is usually fatal in wild bighorn sheep and can reduce the survival rate of lambs born to surviving animals for many years after the initial outbreak. There is no treatment for bighorn sheep, and no preventative vaccine.

Past pneumonia outbreaks among bighorn sheep in Washington and other parts of the western United States have been linked to contact between wild sheep and domestic sheep or goats that carry Mycoplasma but are unaffected by the bacteria. In 2013, state and federal wildlife managers removed the entire Tieton bighorn sheep herd to prevent an outbreak from spreading to other bighorn herds.

Minimizing interactions between wild bighorns and domestic sheep or goats is the best way to prevent pneumonia outbreaks from occurring in wild bighorn populations. WDFW actively works with sheep and goat owners and other land management agencies to limit those interactions.

WDFW is the primary state agency tasked with preserving, protecting, and perpetuating fish, wildlife, and ecosystems, while providing sustainable fishing and hunting opportunities.