The Gulf of Maine is known as home to a diverse range of species, from groundfish to lobster. An up-and-coming resident, however, is making a big splash. The great white shark, one of the most feared yet most misunderstood marine creatures, is making a new home in Maine’s coastal waters. When one hears the words “great white shark,” the movie Jaws might come to mind, a reminder of the film’s lasting effect on the public perception of great whites. In recent years, rumors have been swirling about the shark’s presence in the Gulf of Maine. Though multiple sightings have made the news, the truth behind the great white’s presence in the area still seems to be fuzzy. As sightings increase, so does fear among beachgoers. The question remains: just how many great whites are in Maine waters? To answer that question, Dr. James Sulikowski of the University of New England (UNE) has partnered with NOAA and the Atlantic White Shark Conservancy to tag and track great white sharks to better understand them and their presence in Maine waters. Sulikowski and Dr. Greg Skomal, senior scientist at the Massachusetts Division of Marine Fisheries, have installed tracking receivers in southern Maine waters. Every time one of 120 acoustically-tagged sharks swims past a receiver, Sulikowski and Skomal are notified. The project is ongoing and will provide much-needed information on these elusive predators.
White sharks are close to the limit of their biological range along the Maine coast. The Western Atlantic population is known to migrate as far north as Newfoundland in the winter and as far south as the Gulf of Mexico in the summer. As the Gulf of Maine continues to warm, the extent of the shark’s range is expanding, potentially bringing more into our coastal areas. It’s still unclear how climate change might be affecting great whites. The species is endothermic, meaning they can alter their body temperature and thrive in cooler or warmer waters, rather than simply migrating in response to temperature changes. Thus these sharks may be less influenced by warming ocean temperatures due to their ability to tolerate these changes. These apex predators (that is, a species at the top of the food chain) are also known to follow their food, which ranges from other fish to small whales and pinnipeds such as seals. Given the prominence of seals in the Gulf of Maine, it’s likely that white sharks are simply following their prey of choice. By helping to control seal populations, which are booming in Maine, the sharks help maintain a balanced ecosystem. Spiny dogfish, tuna, and harbor porpoises are also on the menu for great whites, and all are in great abundance in Maine waters. White sharks are found around the globe and are the largest predatory shark on the planet. They can grow up to 20 feet, and weigh up to 4,000 pounds. Great white sharks are protected in the United States and have been since 1991. Since then the population has been on the rise. The UNE tagging project has provided useful information about the presence of great white sharks in the Gulf of Maine, but Sulikowski believes that more data are needed to establish how many sharks may be taking up residence in Maine waters and for how long. Shark experts note that there is no need to worry that Maine’s coastal areas are turning into great white shark–infested waters. While they do make more attacks on humans than any other shark, great white attacks are quite rare. There were only 35 reported fatal attacks between 1990 and 2013 throughout the world. The last fatal attack by a great white in Massachusetts was over eighty years ago, and there aren’t any attacks on record in Maine, according to the International Shark Attack File at the University of Florida. We must learn to live peacefully with great white sharks, Sulikowski said. “The ocean is the shark’s environment. We’re invading their environment,” Sulikowski said in an interview published in the Portland Press Herald. “We have to figure out how to interact with them.”
Abigail Haynes is a marine biology major and English minor at the University of New England. She works for Dr. James Sulikowski conducting research on the age and growth of stingrays and sharks.
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