About 50 eagles descended on the uncovered truck Friday when it left a garage at the Ocean Beauty Seafoods plant, the Anchorage (Alaska) Daily News reported Saturday.
Gorging themselves, the birds pushed each other into the heavy, thick, goo and were drowned, buried and crushed, said federal wildlife officials.
The incident took only minutes and factory officials moved the truck back inside once they saw what was happening, the Daily News reported.
Workers shoveled through the fish guts to find birds, which were taken to a "triage" room and treated by employees from the Kodiak National Wildlife Refuge. Thirty surviving eagles were taken to refuge headquarters to be kept indoors and evaluated further, the Daily News reported.