MARBLEHEAD — Snake populations are booming on the Lake Erie shores and islands in northwest Ohio, and one expert says the reason is there’s plenty of food.

WEWS-TV reported it found large numbers of water snakes swimming in the lake, sunning themselves on rocks and even slithering onto boats in Ohio communities along the lake’s western end.

Ohio State University researcher Kristin Stanford told the Cleveland television station the snakes are northern water snakes and Lake Erie water snakes, which are harmless. She said their numbers are exploding because the lake is full of round goby fish, an invasive species the snakes feed on.

Stanford said the islands are home to an estimated 12,000 Lake Erie water snakes. She works out of Ohio State’s Stone Laboratory field station on South Bass Island.