News Photo by Steve Schulwitz First responders exit a rescue boat after responding to medical emergency on Lake Huron. A 77-year old man died after his boat became unstable in rough and shallow waters today.

ALPENA — A 77-year-old man was pronounced dead after being found unresponsive aboard a sailboat on Lake Huron.

Deputies from the Alpena County Sheriff’s Office and paramedics from the Alpena Fire Department responded early this afternoon to a report of a medical emergency aboard a sailboat disabled outside Thunder Bay.

When rescue crews arrived they found the man unresponsive. He was pronounced dead after emergency medical crews were unable to resuscitate him.

The victim, whom officials did not identify, was from Kalamazoo.

The victim, his wife, and their adult son were en route to Lake Michigan when the boat was overcome by large waves, the Alpena County Sheriff’s Office said in a news release.

According to the man’s wife, the conditions on the lake deteriorated while they were underway and the waves were high. While trying to tuck the boat behind an island, the boat ran aground and the rudder broke off the craft, leaving it unable to navigate.

The U.S. Coast Guard rescue helicopter was dispatched from Traverse City, but returned to its base after the boat was located.

It wasn’t immediately clear if the man died before or after the boat became disabled. The cause of death also wasn’t immediately known.

A sheriff’s deputy said the waves were as high as 8 feet near where the boat was found north of Thunder Bay Island.

A tow boat was used to drag the 30-foot sailboat back to shore.

Michigan Department of Natural Resource officers assisted in the rescue, and a National Oceanic and Atmospheric Administration federal officer also was on scene.