Thomas TinHan releasing a bull shark after tagging in Galveston Bay.

A doctoral student in the Shark Biology & Fisheries Science Lab at Texas A&M University at Galveston is studying the movement and habitat patterns of bull sharks in Galveston Bay with support from Texas Sea Grant’s Grants-In-Aid of Graduate Research Program.

Thomas TinHan is tagging juvenile bull sharks (Carcharhinus leucas) to learn more about their habitat preferences through long- and short-term movement tracking. Texas estuaries are essential nursery habitats for the sharks, but these areas vary greatly in habitat type and regularly experience drastic changes in environmental conditions like temperature and salinity.  By tagging the sharks and then observing where they go over time, TinHan hopes to learn more about how they respond to these changes.

“I’ve always had an interest in studying the behavior of apex predators,” he said.  “They typically play very important roles in marine ecosystems.”

By studying one of the top predators in Galveston Bay, TinHan said that more can be learned about the food chain as a whole, which can then be used to inform management and fishing practices in Texas bays.

“Some ecosystems are very tightly linked,” he said.  “If you adjust the population of one species it could affect several other species, or it might not.  But it’s important we understand how much influence that might have, and the first step of getting at that is understanding the first link in the chain.”

Source: Texas A&M University at Galveston