(NEWS CENTER Maine) -- A shark expert from the University of New England said drawing a scientific conclusion about why a shark attacked a man in Massachusetts on Saturday afternoon is difficult.

Dr. James Sulikowski, a marine biologist and professor at the University of New England, said these interactions are rare.

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"I think that when you look at it from the big picture, still the statistics are so small that you are going to be involved in some form of attack or incident or something with a shark that the statistics are really in our favor. I know we often don't think about that when I happens, but you always have to be diligent," said Dr. Sulikowski. "Typically what happens is the sharks follow food source. They are driven by that food stores and when we have a lot of that food source in a certain area, an area that we are in, you get these types of unfortunate and sometimes very deadly, catastrophic interactions."