This Sept. 26, 2018 file photo provided by the National Park Service shows NPS staff unloading a crated gray wolf from a United States Fish & Wildlife Service aircraft at Isle Royale National Park in Michigan. Credit: National Park Service via AP, File

Wolves on a remote island in Lake Superior appear to be thriving, but they're making deep dents in the moose population that they rely on as a leading food source, according to a report released Monday.

Isle Royale is a 134,000-acre (54,200-hectare) national park in far western Lake Superior between Grand Marais, Minnesota, and Thunder Bay, Canada. The island is a natural laboratory, offering scientists a rare opportunity to observe wolves and moose largely free from human influence.

Researchers have conducted wolf and moose population surveys on the island since 1958.…