Tiger sharks are among the largest and most recognizable sharks on the planet, yet many of their habits remain mysterious because they are long-distance travelers that are hard to track.
But a new study, reported in the June 9, 2015 issue of the journal Scientific Reports, has yielded the first ever continuous, two or more-year satellite tagging tracks for the animals. This study reveals remarkable, and previously unknown, migration patterns more similar to birds, turtles and some marine mammals than other fishes.
The study was led by James Lea and Brad Wetherbee, Ph.D., co-first authors, and senior author, Mahmood Shivji, Ph.D., all of whom work out of Nova Southeastern University’s (NSU) Guy Harvey Research Institute in Florida. Renowned marine artist and conservationist Guy Harvey, a Ph.D. fisheries ecologist, is also an author on the paper and co-led the project’s tagging work, which took place near Bermuda, in collaboration with the Bermuda Shark Project.
Long believed to be mainly a coastal species, the tiger sharks, in fact, made more than 7,500 kilometer, round-trip journeys every year between two vastly different ecosystems – the coral reefs of the Caribbean and the open waters of the mid-North Atlantic. Furthermore, they returned reliably to the same overwintering areas each year, a discovery with significant conservation implications.
“As apex predators, the presence of tiger sharks – and other large sharks – is vital to maintain the proper health and balance of our oceans,” said Dr. Shivji, who is professor at NSU’s Halmos College of Natural Sciences and Oceanography and also the director of NSU’s GHRI. “That’s why it’s so important to conserve them, and understanding their migratory behavior is essential to achieving this goal.”
You can read the full media release here.