麻豆淫院

A scientific report says the wolf population of Isle Royale National Park in Lake Superior is dangerously low for the third consecutive year, while moose numbers are steadily rising.

The Associated Press obtained the report Wednesday ahead of its scheduled release by Michigan Technological University.

The study is the world's longest of a predator-prey relationship in a closed ecosystem. Biologists have studied the island's wolves and moose since the late 1950s.

Historically, wolves have kept moose in check and prevented them from overeating island vegetation.

But just nine wolves were counted this winter. That's just one more than the eight that roamed the island last year, which was the lowest total on record.

Meanwhile, moose numbers have doubled over the past three years and are estimated at 1,050.