A new study led by scientists at the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science tracked large sharks in Miami and The Bahamas to understand how these migratory animals respond to major storms, like hurricanes.
The researchers analyzed acoustic tag data from tiger sharks (Galeocerdo cuvier), bull sharks (Carcharhinus leucas), nurse sharks (Ginglymostoma cirratum), and great hammerheads (Sphyrna mokarran) before, during, and after Hurricane Matthew in 2016 and Hurricane Irma in 2017. They found that they behaved differently by species and location.
For example, in response to Hurricane Irma passing by Miami, bull sharks, great hammerhead, and most nurse sharks appeared to mostly evacuate the shallow waters of Biscayne Bay, similar to previous studies that found that small sharks evacuate inshore shallow waters in the wake of a storm. However, large tiger sharks in the Bahamas remained in shallow inshore waters, even as the site received a direct hit from the eye of the category-5 Hurricane Matthew, and immediately following the storm, the number of tiger sharks doubled.
Read More: University of Miami Rosenstiel School of Marine and Atmospheric Science
Locations of the Bahamas and Miami study areas in relation to the paths of Hurricane Matthew (a, path of eye as dot-dash line) and Hurricane Irma (a, path of eye as dashed line). The 64 knot (minimum sustained wind speed to categorize a hurricane) radii are indicated by grey shaded regions along each hurricane path. (Photo Credit: Figure from Gutowsky et al. (2021 Tiger shark: Neil Hammerschlag Ph.D., University of Miami Rosenstiel School of Marine and Atmospheric Science)