Bite Size: Bull Shark Predation of Tarpon

Vimeo Link:

Neil Hammerschlag, University of Miami

Gareth Burghes, Lagomorph Films


Predators can impact ecosystems through trophic cascades. Both bull sharks and tarpon are large predatory fish in tropical waters. They occupy similar inshore habitats and having similar diets; but, if given the opportunity, bull sharks will catch and consume tarpon. However, it remains unknown if tarpon adjust their movements to avoid being killed by the sharks. In this study, both bull sharks and tarpon were satellite tagged to track their movements in South Florida waters. The results showed that tarpon avoided the areas where bull sharks aggregated. In fact, tarpon appeared to forfeit some of the best feeding spots to reduce their chances of being killed by sharks.  These results suggest that overfishing of bull shark could impact the behaviors of tarpon, subsequently triggering trophic cascades.


Hammerschlag N, Luo J, Irschick DJ, Ault JS (2012) A Comparison of Spatial and Movement Patterns between Sympatric Predators: Bull Sharks (Carcharhinus leucas) and Atlantic Tarpon (Megalops atlanticus). PLoS ONE 7(9): e45958. doi:10.1371/journal.pone.0045958

Click here to access the full publication

 Learn More

Follow Dr. Hammerschlag's research on his website:

By the Numbers

Over 40,000 students in 50 US states, the US Virgin Islands, and 25 countries participated as judges in the 2016 Ocean 180 Video Challenge.