The agency announced Friday that the carcass of an adult ewe killed by a mountain lion was found Jan. 15.
The state wildlife agency released 31 bighorn sheep into the Santa Catalina Mountains on Nov. 18.
The agency says seven of the deaths were caused by mountain lions. Game and Fish personnel still haven't located the mountain lion in the most recent killing.
The first death was an adult ram found Nov. 27. Authorities say the death was likely caused "capture myopathy," a condition in which a build-up of lactic acid in muscle tissue can lead to heart failure.