ELLSWORTH, MAINE—The alleged kingpin of one of the biggest domestic wildlife smuggling operations ever to hit the East Coast is exactly where you’d expect to find him on a rainy evening in early May: firmly planted in a swivel chair at a big green metal desk inside his renovated Quonset hut on Foster Street, in Ellsworth, Maine.

At this post Bill Sheldon waits day and night for fishermen to come and fill his bowl with writhing masses of baby eels.

The 72-year-old fisherman wears glasses, a blue flannel shirt, jeans, duck boots, and a brown L.L. Bean baseball cap. His cell phone goes quack, quack, quack when it rings. The sign above his head reads, “Buying Glass Eels Here,” with the day’s