Three bighorn ewes found dead in recent weeks in the Catalina Mountains suffered from respiratory infections resulting in pneumonia, says a report released Friday by the Arizona Game and Fish Department.
The report from the department, which is overseeing efforts to rebuild a bighorn herd in the Catalinas north of Tucson, said necropsies and lab results revealed the findings.
“Pneumonia can have serious impacts on bighorn sheep populations, and it is possible that additional mortalities may occur in the coming months,” the report said. “Impacts can be particularly severe for lamb recruitment.”
Treatment for pneumonia in bighorn sheep is not an option, according to the report.
“There is currently no effective vaccine or antibiotic,” it said.
“Past attempts to treat this disease in bighorn sheep have either had no effect, or efforts have had a negative impact on already compromised sheep. The department is investigating the source of the infection.”
Game and Fish officials said 37 GPS-collared bighorns are known to be alive in the Catalinas.
It’s uncertain how many bighorn lambs might be in the range.
“Lambs born in the Catalinas are not collared, but the department has been observing ewe and lamb groups over the past several months,” officials said. “Biologists are in the field in an attempt to determine current numbers of uncollared sheep.”
