The collapse of the bay scallops (Argopecten irradians) fishery in North Carolina is linked to the rise in numbers of scallop eating cownose rays (Rhinoptera bonasus), due to overfishing of the predatory sharks which once kept ray numbers in check. (sciencedaily.com)
Large sharks continue to dwindle while other species, such as clam - eating cownose rays, have exploded in the absence of predators. (scientificamerican.com)
Other rays such as cownose rays, swim together, but typically in schools of their own species. (newscientist.com)