A new study conducted by Montana State University shows some interesting information. According to Scott Creel, ecology professor who headed the study, pregnancy rates in cow elk dropped significantly when exposed to wolves. Enough so that the study concluded that the drop in new-born calves was bigger due to fewer pregnancies than with wolves eating the calves.
“Elk in the absence of wolves go about their business in one way, they go about the task of feeding themselves, then you put wolves on the landscape and now they have two priorities to trade off one another,” Creel said. “They have a behavioral response to wolves. They carry costs.”
This is believed to be the first study that shows how wolves affect elk populations. It has always been talked of and assumed that wolves reduce elk populations simply by killing them. This study reveals that bears are the number one killer of new-born elk before one year of age but that the birth rate drops significantly when wolves are present.
In the Gallatin Canyon herd, there were just eight calves per 100 cows.
Generally, 30 calves per 100 cows is considered a solid ratio to sustain a herd.
For more information about his study, visit the Billings Gazette online.
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