Great white sharks are among the largest, most widespread predators in the ocean, and ones that Hollywood loves to hate. But, they are surprisingly quite vulnerable, though new research shows that populations show promise of making a comeback.
"White sharks possess life history traits that make them vulnerable to exploitation," co-author Nancy Kohler, chief of the Apex Predators Program at NOAA's Northeast Fisheries Science Center (NEFSC), said in a statement.
"These sharks can live 70 years or more, mature late, and do not produce many young. Their status and highly valued jaws and fins have made them the target of recreational and trophy fisheries in areas where their populations are not protected."
The study, published in the journal PLOS ONE, used records over the last 200 years to compile the most comprehensive set of data on seasonal distribution patterns and historic trends of great white sharks, or Carcharodon carcharias, in the North Atlantic Ocean. While scientists certainly have a number of recorded sightings of white sharks, data previously available made it difficult to pin down just where they would be and when.
"White sharks in the Northwest Atlantic are like a big jigsaw puzzle, where each year we are given only a handful of pieces," said study leader and shark researcher Tobey Curtis.
But finally the picture is becoming clearer. Based off results, these marine predators can be found between Massachusetts and New Jersey during the summer months, off the Florida coast during winter, and have a broader range along the East Coast during spring and fall. Their migratory patterns depend on environmental factors such as water temperature and the availability of prey. For instance, large colonies of gray sea lions off the coast of Massachusetts have not gone unnoticed by these sharks.
"After decades of effort by a lot of researchers, we finally have enough puzzle pieces for a picture to emerge on distribution and abundance patterns. We are pleased to see signs of population recovery," Curtis said.
Scientists hope this detailed research provides ideas of better conservation and management tools of white sharks both regionally and internationally.