15-September-2021 (written by Hannah Calich)
The Sequeira Lab is excited to announce that research led by our PhD student Hannah Calich on the movement patterns of sympatric apex predatory sharks has just been published in Ecography: ‘Comprehensive analytical approaches reveal species-specific search strategies in sympatric apex predatory sharks‘. In this research, done in collaboration with Jorge P. Rodríguez, Víctor M. Eguíluz, Neil Hammerschlag, Charitha Pattiaratchi and Carlos M. Duarte, we used novel analytical techniques derived from statistical physics to determine the movement strategies of three shark species. We found that tiger, great hammerhead, and bull sharks use complementary movement and search strategies within the Northwest Atlantic Ocean and Gulf of Mexico, that may help support their co-existence by reducing niche overlap.
We analysed data from 96 sharks across the three species. Overall, tiger sharks followed a near-random movement strategy, bull sharks followed a more restricted movement strategy, and great hammerheads showed a mixed movement strategy consisting of random and resident movements. These species-specific movement patterns are consistent with dietary requirements for these species meaning the movement strategies we identified may be key in supporting their co-existence.
Congratulations to Hannah for this great achievement, and thanks to all of the University of Miami’s Shark Research and Conservation Program team members who assisted in tracking data collection.
Bull, great hammerhead, and tiger sharks in Florida, USA and the Bahamas.
Photo credits: Christine Shepard, Neil Hammerschlag (www.sharktagging.com), Frank Gibson