Cassirer honored for work to save bighorns

An Idaho Fish and Game biologist who helped identify the pathogen killing bighorn sheep and develop a management regime to reduce the impact of the disease was recently honored by the Idaho Wild Sheep Foundation.

Frances Cassirer, who works out of the agency’s Clearwater Region based in Lewiston, was given the wildlife group’s Statesman Award.

“Frances is a leader among our state and regional partners, and her research is cutting edge,” said Idaho Wild Sheep Foundation President Bill London. “She has the respect and admiration of our partners and is seen as an individual who is an expert in the field of bighorn sheep research and management.”

According to a news release, the award is presented to government officials for their outstanding contributions to wild sheep conservation. Cassirer has worked to recover bighorn sheep in the Hells Canyon region for more than 25 years. The sheep were exposed to a pneumonialike illness in the 1990s that swept through the herds and led to significant die-offs. The illness continued to sicken animals and lead to poor lamb survival for more than 20 years.

Cassirer, working with colleagues at Washington State University, zeroed in on the bacterium Mycoplasma ovipneumoniae, also known as Movi.

She developed the test-and-remove program that has helped bighorn sheep herds begin to recover from the disease. Under the program, wildlife officials test bighorn herds for Movi and remove those that are chronic carriers.

The test-and-remove program now is being used in several Western states where Movi has affected wild sheep herds.

“Frances has dedicated her career to using research to resolve disease issues that have plagued bighorn sheep for decades,” said Fish and Game Wildlife Bureau Chief Jon Rachael. “Her efforts have turned the tide for bighorn sheep management. Thanks in large part to Frances’ work, managers now have a tool that can be used to improve the health of bighorn sheep, increase survival and overall bighorn sheep numbers.”

Her research, coupled with data from other biologists in the Hells Canyon region, has led to a better understanding of sheep migration and development of a model that helps biologists estimate disease risk to nearby herds.

Cassirer was presented the award at the Wild Sheep Foundations annual convention in Reno, Nev.