UNF researchers working to protect shark populations
It’s a quiet morning on the St. Mary’s River as a group of researchers heads out on assignment.
The assignment you might ask? To find as many sharks as possible.
“We’re in our sweet spot!” calls out University of North Florida Shark Biology Program Director Dr. Jim Gelsleichter.
To some, it may be a bit eerie these researchers are looking for sharks so close to shore. To others, this study means vital information to protect and preserve this species.
“This is, in many cases, something we’ve wanted to do all our lives,” commented Gelsleichter. “That’s certainly the case for me, but there is a purpose to the work that we do.”
The first hook of the day comes in.
“Sandbar!” yells one of Dr. Gelsleichter’s students. “Yeah!”
The researchers are ecstatic. As they pull the shark out of the water, they quickly position it to the front of the boat to take measurements, draw blood for hormone testing and evaluate its overall well-being.
What feels like a matter of seconds, the shark is tagged and carefully released back into the ocean.
“So, the idea is when we’re managing fisheries and we’re managing populations that are exploited, we need to not just manage the population, but also manage the habitat,” Gelsleichter added.
The sandbar sharks caught on this trip, for example, have a very slow reproduction rate. Overfishing in the late 80’s and early 90’s significantly reduced their population to the point where commercial fishing for the species is now banned.
Since 2009, the government has funded Gelsleichter’s project and data shows it has paid off.
“We’ve got a lot of success,” said Gelsleichter. “We’re starting to see some shark populations that we saw declined considerably in the 1980’s start to rebound, start to rebuild and that’s been a really wonderful thing to see.”
Dr. Gelseichter is working to come up with a pregnancy test for sharks, nothing like it currently exists. This tool would be helpful for researchers to understand where exactly sharks are giving birth.
If researchers had more information on where the sharks are giving birth, they can then work with fisheries and shrimp trolling companies to make sure they stay away from breeding or birthing grounds during certain times of year.
Dr. Gelsleichter and his crew race against the clock every time they’re out for a research trip, but without their work it could be the end of the line altogether for these sharks.