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The May 2013 issue of  Commercial Fisheries News features an article about the Maine Fisherman’s Forum session titled “Our Changing Ocean—What Factors May Be Inhibiting Groundfish Recovery.”  James Sulikowski, Ph.D, associate professor in the Department of Marine Sciences, attended the forum, and the research about spiny dogfish that he shared at the forum was highlighted in the article.

Dogfish often prevent successful catches of ground fish because the sheer number of them clog nets.  They are also aggressive feeders, ripping through nets to devour fish that have been caught.  Fishermen have long suspected them as a major culprit in dwindling ground fish numbers.

Sulikowski has worked for several years with fisherman to debunk some of the myths surrounding spiny dogfish.  Using satellite tags, he has collected depth, temperature, and migration data about the species. 

One assumption about dogfish that Sulikowski reported as untrue to the session attendees is the belief that dogfish, as a rule, come north in the spring and head south for the Mid-Atlantic waters in the fall.  Actually, according to Sulikowski, the vast majority of spiny dogfish that were tagged in the Gulf of Maine appear to remain in New England waters year-round, moving in a circular pattern.

Sulikowski’s research has also shown that the range of temperature and depth of water in which dogfish swim is more variable than once thought.  In addition, he has found that the species’ reproductive cycle is shorter than previously assumed.

Some of the new evidence about spiny dogfish behavior that Sulikowski’s research has uncovered indicates that previous surveys of dogfish numbers were likely inaccurate.  The article states: “Many fishermen, especially those who have long suspected that dogfish were being missed by trawl surveys, say they feel vindicated by much of this latest research.”