Killing sharks to reduce depredation is not the answer

Shark depredation, the full or partial consumption of a hooked fish by a shark before it is landed, is an increasing source of human and wildlife conflict in recreational fisheries. This summer and fall, and for the past three to four years, we have had enhanced reports of sharks being caught close to shore off Newport, Narragansett and the Sakonnet River area.

Along with this, we have had an increase in shark depredation, with anglers reeling in summer flounder (fluke) and striped bass to find the fish has been bitten by a shark.

Last week a study led by U. Mass Amherst was published in Marine and Coastal Fisheries, titled “Depredation rates and spatial overlap between Great Hammerheads and Tarpon in a recreational fishing hot spot.”

Reports of shark depredation in the catch-and-release Tarpon fishery in the Florida Keys are increasing, specifically in Bahia Honda, a recreational fishing hot spot and a known Tarpon pre-spawning aggregation site.

Highlights of the study abstract appear below; the entire study can be found at Depredation rates and spatial overlap between Great Hammerheads and Tarpon in a recreational fishing hot spot - Casselberry - 2024 - Marine and Coastal Fisheries - Wiley Online Library.

The study suggests that culling or killing sharks is not the answer, but rather reducing fight times and ending a fight prematurely when sharks are present should be explored. Here are the highlights.

Methods: Using visual surveys of fishing in Bahia Honda, scientists quantified depredation rates and drivers of depredation. With acoustic telemetry, scientists simultaneously tracked 51 Tarpon and 14 Great Hammerheads (also known as Great Hammerhead Sharks) Sphyrna mokarran, the most common shark to depredate Tarpon, to quantify residency and spatial overlap in Bahia Honda.

Result: During the visual survey, 394 Tarpon were hooked. The combined observed shark depredation and immediate post release predation rate was 15.3% for Tarpon that were fought longer than 5 minutes. Survival analysis and decision trees showed that depredation risk was highest in the first 5 to 12 minutes of the fight and on the outgoing current.

During the spawning season, Great Hammerheads shifted their space use in Bahia Honda to overlap with Tarpon core use areas. Great Hammerheads restricted their space use on the outgoing current when compared to the incoming current, which could drive increased shark–angler interactions.

Conclusion: Bahia Honda has clear ecological importance for both Tarpon and Great Hammerheads as a pre-spawning aggregation and feeding ground. The observed depredation mortality and post release predation mortality raise conservation concerns for the fishery.

Efforts to educate anglers to improve best practices, including reducing fight times and ending a fight prematurely when sharks are present, will be essential to increase Tarpon survival and reduce sharka-angler conflict.

Fishing and offshore wind energy workshop Feb. 7

Join the free online workshop, titled “Recreational Fishing and Offshore Wind Energy: Understanding the Changing Behavior,” on Wednesday, Feb. 7, from 5 to 7:30 p.m. (EST).

Webinar organizer Jennifer McCann, director of U.S. Coastal Programs at the Coastal Resources Center, URI Graduate School of Oceanography, and director of Extension Programs for Rhode Island Sea Grant, said, “The purpose of this effort is to advance our shared understanding of impacts and changing behavior of recreational fishers due to the accelerated growth of offshore wind energy and identify strategies to respond to research and monitoring needs. During this initial webinar, we will communicate some of the current research and monitoring strategies, identify gaps, and strategize mechanisms to fill these gaps.”

This effort is part of the NOAA/URI CRADA to advance collaborative research and ocean planning solutions on the interactions of offshore wind energy development and marine ecosystems, inclusive of humans and coastal communities.  

Registration by Feb. 5 is required for this free and public event to assist with logistics. To register, visit https://docs.google.com/forms/d/e/1FAIpQLSd9U4TNVjkhlfy3FMZATa9KC26zEIS9snChMtSW1WJgBr5uag/viewform.

Confirmed Panelists for the webinar are: Emma Chaiken, economist, Bureau of Ocean Energy Management; Doug Christel, fisheries policy analyst, GARFO/NOAA); Tony DiLernia, captain, recreational fisheries liaison, NYSERDA – contractor; Walt Golet, School of Marine Sciences, University of Maine; Todd Guilfoos, associate professor, Environmental and Natural Resource Economics (ENRE), University of Rhode Island (URI); Jeff Kneebone, senior scientist, Fisheries Science and Emerging Technologies Program, NE Aquarium; Julia Livermore, deputy chief of Marine Fisheries, R.I. Department of Environmental Management; Travis Lowery, fisheries liaison, Vineyard Wind; Andy Lipsky, Cooperative Research Branch chief, Narragansett Laboratory director, NEFSC/NOAA; Dave Monti, captain, No Fluke Charter Fishing & Tours; Scott Steinbeck, economist, NEFSC/NOAA; Tiffany Smythe, associate professor, U.S. Coast Guard Academy; Scott Travers, executive director, Rhode Island Saltwater Anglers Association; and Jeff Willis, executive director, R.I. Coastal Resources Management Council.

Annual RISAA Banquet, Feb. 17

“This year we are holding our annual banquet on Feb. 17, 2024, at the Quonset ‘O’ Club,  200 Lt. James Brown Road, North Kingstown, RI,” said Scott Travers, executive director of the Rhode Island Saltwater Anglers Association (RISAA). Cocktails and hors-d’oeuvres will start at 5 p.m., with dinner at 6 p.m.

“We welcome all our fellow members to come and celebrate our 2023 Annual Tournament winners and other award recipients. We will have raffle items available including two charter trips and much, much more,” said Travers.

Tickets are now available on the RISAA Website. Go to the “MEMBERS AREA” and click on the “Members Home” page to get your tickets now.  Contact Scott Travers at 401-826-2121 or travers@risaa.org for further information.

Where’s the bite?

Freshwater fishing in stocked ponds for trout and salmon continues to be good. with a largemouth bass bite, too. For a complete list of trout stocked ponds in Massachusetts visit Mass Wildlife at Trout stocking report | Mass.gov  and in Rhode Island visit www.dem.ri.gov/fishing, or call 401-789-0281 or 401-539-0019 for more information on trout stocking.

Saltwater fishing has been limited with high winds and storms.  However, anglers continue to catch school striped bass and an occasional keeper in salt ponds and estuaries.  If you want to try your hand at cod fishing call ahead to make a party boat reservation, vessels will sail once the weather clears. Visit www.islandcurrent.com and www.francesfleet.com.

Dave Monti holds a captain’s license and charter fishing license. He serves on a variety of boards and commissions and has a consulting business focusing on clean oceans, habitat preservation, conservation, renewable energy, and fisheries related issues and clients. Forward fishing news and photos to dmontifish@verison.net or visit www.noflukefishing.com.