The Bluewater Anglers' 43rd annual salmon derby begins at 12:01 a.m. on Friday and continues until May 12 at 3 p.m.
It's a boat and shoreline event, with boundaries ranging from Fawn Island to Grand Bend and up the US side to Lexington.
Spokesman Paul Heckley expects about 1,100 people to take part.
He said $40,000 in prizes are up for grabs, including $5,000 for the largest salmon.
"We've got ten prizes for the ten largest salmon, and five prizes in the other four categories which are lake trout, walleye, rainbow and brown trout caught from shore, and rainbow and brown trout caught from a boat," he said.
Money raised from the derby helps the organization fund up to two-thirds of the hatchery operation for the year.
Last year, Grand Bend's Justin Tadgell caught the heaviest fish with a record-breaking 26.64-pound lake trout.
Rick Scott of St. Marys won the salmon category with a 14.12-pound catch.
