“With fewer sharks around, the species they prey upon – like cownose rays – have increased in numbers and in turn, hordes of cownose rays dining on bay scallops have wiped the scallops out. Large sharks have been functionally eliminated from the east coast of the U.S., meaning that they can no longer perform their ecosystem role as top predators. The extent of the declines shouldn’t be a surprise, considering how heavily large sharks have been fished in recent decades to meet the growing worldwide demand for shark fins and meat. With an average population increase of about eight per cent per year, the east coast cownose ray population may now number as many as 40 million. The rays (which can grow to be more than four feet across) eat large quantities of bivalves, including bay scallops, oysters, soft-shell and hard clams, in the bays and estuaries they frequent during summer and migrate through during fall and spring.Our study provides evidence that the loss of great sharks triggers changes that cascade throughout coastal food webs. Solutions include enhancing protection of great sharks by substantially reducing fishing pressure on all of these species and enforcing bans on shark finning both in national waters and on the high seas. " Julia Baum stated in an interview on the eve of Science journal's publication of her research with Dr. Ransom Myers.
Dr. Myers passed away on the eve of the publication of this study. His passing has deeply affected the Dalhousie community, but his legacy remains in the form of continued meaningful research in the Myers Lab that has the potential to change the world for the better. This research is a fitting way to honour his memory. http://dalnews.dal.ca/2007/03/29/scallop.html
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