Graduate Student Spotlight
Fall 2014 - Brendan Talwar
As many coastal fish stocks have declined and technology has advanced, industrial fishing fleets have turned their attention to the deep sea. Many deep sea fishes are slow growing, mature late, and have few offspring, making them highly vulnerable to exploitation and risk of extinction. Deep sea sharks are at the extreme end of this spectrum, with gulper sharks often cited as one of the least resilient species in all of our oceans. Despite this concern, both the gulper shark Centrophorus sp. and the Cuban dogfish Squalus cubensisare common bycatch (non-target) species in deep water longline and trawl fisheries that operate below 200m. They often experience high mortality rates when pulled to the surface due to severe temperature, pressure, and light related stress. Those still alive at the boat are either released and presumed to survive or, conversely, killed under the assumption that none will survive after release.
Brendan's primary research goals are 1) to estimate accurate post-release survivorship probabilities after longline capture in the tropics; and 2) to better understand why some sharks die while others survive. Over the past few months, Brendan has collected data in the Gulf of Mexico and Eleuthera (Bahamas), where he currently teaches a high school semester abroad course focused on the post-release survivorship of Cuban dogfish.