A whale carcass was discovered stuck on the bow of the Sapphire Princess on Wednesday morning, while the ship was south of Juneau near Tracy Arm, reported the Anchorage Daily News.
The newspaper said the ship called the Coast Guard, which determined that the whale appeared to be a juvenile humpback.
A tugboat crew worked to dislodge the carcass, delaying the cruise for a few hours. The Sapphire Princess is on a seven-day Alaska cruise out of Seattle.
A necropsy will be conducted to determine the cause of death.
Last July, a dead fin whale was discovered on the bow of the Sapphire Princess while returning to Vancouver from an Alaska cruise. A necropsy determined that the whale was dead for days before the ship hit it.