Image of the Day: Fewer Sheep Despite Predator Control

Sheep numbers have declined despite decades of U.S. government-subsidized predator control; but it's not the predator's fault--it's market forces, according to a new study by the Wildlife Conservation Society (WCS).

Predation by coyotes is often cited as the primary cause of the decline, accounting for 75 to 95 percent of sheep killed annually. However, other animals, such as mountain lions, bobcats, wolves, black bears and grizzly bears are also to blame.

The government has invested more than 1.6 billion dollars over the course of more than 80 years to stave off an 85 percent decline in the sheep industry. Despite this, the sheep industry has continued to drop since its peak of 56.2 million animals in 1942. A review of historical data suggests that a variety of market trends, ranging from fluctuating hay prices and rising wages for livestock workers, to the drop in wholesale prices of lamb and wool, are the real culprits behind the decline, the researchers write.

As evidence, the study points to a 141-percent increase in wages, 23 percent decrease in lamb prices, and 82 percent decrease in wool prices during the period in which sheep numbers were reduced by 85 percent.

"This is an industry whose profitability has been squeezed from both sides," said WCS study leader Kim Berger.

The study is detailed in the latest issue of the journal Conservation Biology.