Saving Seafood

New shark research targets a nearly endangered species

September 16, 2020 — They are some of the most iconic and unique-looking creatures in our oceans. While some may think they look a bit odd, one thing researchers agree on is that little is known about hammerhead sharks. Many of the 10 hammerhead shark species are severely overfished worldwide for their fins and in need of urgent protection to prevent their extinction.

To learn more about a declining hammerhead  that is data poor but in need of conservation efforts, a team of researchers from Nova Southeastern University’s (NSU) Save Our Seas Foundation Shark Research Center (SOSF SRC) and Guy Harvey Research Institute (GHRI), Fisher Finder Adventures, the University of Rhode Island and University of Oxford (UK), embarked on a study to determine the migration patterns of smooth hammerhead sharks (Sphyrna zygaena) in the western Atlantic Ocean. This shark, which can grow up to 14-feet (400 cm), remains one of the least understood of the large hammerhead species because of the difficulty in reliably finding smooth hammerheads to allow scientific study.

To learn about smooth hammerhead behavior, the research team satellite tagged juvenile hammerhead sharks off the US Mid-Atlantic coast and then tracked the sharks for up to 15 months. The sharks were fitted with fin-mounted satellite tags that reported the sharks’ movements in near real time via a satellite link to the researchers.

“Getting long-term tracks was instrumental in identifying not only clear seasonal travel patterns, but importantly, also the times and areas where the sharks were resident in between their migrations,” said Ryan Logan, Ph.D. student at NSU’s GHRI and SOSF SRC, and first author of the newly published research. “This study provides the first high resolution, long term view of the movement behaviors and habitats used by smooth hammerhead sharks—key information for targeting specific areas and times for management action to help build back this depleted species.”

Read the full story at PHYS.org

Open Sores, Lower Numbers Likely Not Invasive Lionfish’s End

February 4, 2020 — A new disease has caused open sores that can eat into the muscles of invasive lionfish and appears to have contributed to an abrupt drop in their numbers in the northern Gulf of Mexico, scientists reported Tuesday. But they hasten to say it’s probably far from the end of the showy invader with long, venomous spines.

Lionfish may even already be bouncing back, said University of Florida doctoral student Holden Harris, lead author of the article published online in Scientific Reports. Numbers of the smallest lionfish taken by spearfishers were way down in 2018, indicating a possible reduction in spawning, but were rising late that year and in early 2019, he said.

“It’s too early, really, to say if that’ll become a full population recovery,” he said.

It’s an interesting development, said Matthew Johnston, a Nova Southeastern University researcher who has written scientific papers about invasive lionfish but had not known about the lesions or population changes. “We’ve always been wondering if they’re ever going to reach their limit in certain locations,” he said. “To date it seemed the populations just kept getting larger and larger and larger.”

Read the full story from the Associated Press at The New York Times

NMFS Institutes More Swordfish Research Off Florida, Praised by EDF

August 16, 2017 — SEAFOOD NEWS — Dr. David Kerstetter of Nova Southeastern University will receive an exempted fishing permit (EFP) from the National Marine Fisheries Service (NMFS) to conduct research in the East Florida Coast Pelagic Longline Closed Area. Dr. Kerstetter will be working alongside Atlantic swordfish fishermen in an effort to “improve understanding of encounter rates of juvenile swordfish and species like sharks, bullfishes and sea turtles in order to find the best ways to reduce their mortality.”

According to Katie Westfall, senior manager of highly migratory species advocacy for EDF’s Oceans Program, fishermen have already made sacrifices to help the Atlantic swordfish population rebound. However, this project will help by collecting data from fisheries that “interact with imperiled highly migratory species.”

“The project will also pioneer an approach to link catch data with oceanographic data, allowing researchers to learn over time where and when species will occur in order to help fishermen avoid bycatch of sharks, billfishes, and sea turtles,” Westfall added. “This has the potential to be transformative by dramatically minimizing unnecessary deaths of protected species while improving the catch of healthy target species like swordfish.”

Westfall is hopeful that the research will help “pave the way to responsibly increasing yield in domestic fisheries and strengthening revenues for American seafood businesses.”

This story originally appeared on Seafoodnews.com, a subscription site. It is reprinted with permission.

NORTH CAROLINA: Shark’s 8,500-mile odyssey ends on a fisherman’s hook

December 8, 2016 — A mako shark caught by commercial fishermen off North Carolina traveled more than 8,500 miles after a tracking device was attached 18 months earlier, an ocean research group says.

Researchers studying shark migrations for the Guy Harvey Research Institute at Nova Southeastern University in Fort Lauderdale, Fla., attached the device to the female shark’s dorsal fin in mid-2015 near Ocean City, Md.

A donation to the institute by Heather Finke sponsored the tag in honor of Charlotte Latin School.

A commercial long-line fishing boat caught the shark near Manns Harbor last month. The last of the tag’s 265 data transmissions from the sea to an orbiting satellite was recorded on Nov. 24.

Data show the shark swimming up and down the East Coast (click mako sharks > W. North Atlantic > Charlotte) between North Carolina and Rhode Island, making one big loop into the Atlantic north of Bermuda last spring. It traveled an average of 15 miles a day over 557 days.

“We’re happy to have recovered the satellite tag, but disappointed about the loss of the mako,” said executive director Greg Jacoski of the Guy Harvey Ocean Foundation, which supplies the tags. “It’s important for us to recover tags because of the value they have for our research efforts.”