A 2007 paper argued that the loss of large sharks in the northwest Atlantic had released cownose rays from predation, and that a resulting ray boom had collapsed a North Carolina bay scallop fishery. The argument spread quickly, and campaigns promoting ray fishing and consumption followed.
A detailed rebuttal published in 2016 tested the chain link by link. Cownose rays reproduce very slowly, bearing a single pup after roughly a year of gestation, which cannot generate a rapid population surge. Survey data did not show the required increase. The timing of the scallop decline did not match, and dietary work indicated the rays take mainly thin-shelled clams rather than being specialised scallop or oyster predators.
The episode is a caution about trophic cascade narratives: the story was intuitive, quotable and applied to management before the intermediate steps had been checked.