A novel intrauterine satellite transmitter to identify parturition in large sharks

Science Advances, Journal Year: 2023, Volume and Issue: 9(9)

Published: March 1, 2023

Determining where and when animals give birth is critical for establishing effective conservation management that protects vulnerable life stages (e.g., pregnant females newborns) places nursery grounds). To date, this information has been elusive in the case of highly migratory sharks wild. Here, we report on deployment a novel intrauterine satellite tag implanted two mobile apex predators, tiger shark (Galeocerdo cuvier) scalloped hammerhead (Sphyrna lewini), remotely documented location timing by oceanic animal This technology will be especially valuable protection threatened endangered species, pupping grounds priority.

Language: Английский

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Stay or go? Space and resource use of the great hammerhead (Sphyrna mokarran) off Andros Island, The Bahamas

Frontiers in Marine Science, Journal Year: 2025, Volume and Issue: 12

Published: March 21, 2025

In light of global declines upper-level marine predators, such as the great hammerhead, ( Sphyrna mokarran) a thorough understanding their behavioral ecology is needed for designing effective management strategies to preserve key role in maintaining ecosystem functioning, stability, and resilience. Within northwestern Atlantic, hammerheads display regional connectivity between U.S. East Coast western edge The Bahamas, but despite suggested importance Bahamian shark sanctuary towards population recovery strategies, relatively few data exist from other areas Bahamas. This study used fisheries-independent drumline captures, satellite telemetry, bulk stable isotope analysis advance our residency, space use, trophic Andros, largest island We examined movement behaviors thermal range within Exclusive Economic Zone, constructed Bayesian mixing models based on carbon, nitrogen, sulfur ratios estimate prey species diet hammerheads. Our revealed year-round residency Andros-caught waters with site-fidelity high use habitats along reef-drop off flats Andros. Great predominantly fed barracuda small-bodied elasmobranchs Andros connecting food webs pelagic zone shoreline. expands knowledge Atlantic shows that, highly-mobile nature, some individuals reside Bahamas year round. These findings suggest could be more than just seasonal refuge this previously proposed, merit further research assess conservation value rebuilding goals greathammerheads.

Language: Английский

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Accumulation of Per- and Polyfluoroalkyl Substances (PFAS) in Coastal Sharks from Contrasting Marine Environments: The New York Bight and The Bahamas

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: 58(29), P. 13087 - 13098

Published: July 12, 2024

Per- and polyfluoroalkyl substances (PFAS) enter the marine food web, accumulate in organisms, potentially have adverse effects on predators consumers of seafood. However, evaluations PFAS meso-to-apex predators, like sharks, are scarce. This study investigated occurrence five shark species from two ecosystems with contrasting relative human population densities, New York Bight (NYB) coastal waters The Bahamas archipelago. total detected (∑PFAS) concentrations muscle tissue ranged 1.10 to 58.5 ng g

Language: Английский

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Juvenile survival and movements of two threatened oceanic sharks in the North Atlantic Ocean inferred from tag‐recovery data

Ecology and Evolution, Journal Year: 2023, Volume and Issue: 13(6)

Published: June 1, 2023

Abstract Understanding population dynamics, movements, and fishing mortality is critical to establish effective shark conservation measures across international boundaries in the ocean. There are few survival dispersal estimates of juveniles oceanic species North Atlantic despite it being one most fished regions world. Here we provide dispersal, survival, proportion for two threatened sharks: blue ( Prionace glauca ) shortfin mako Isurus oxyrinchus ). Our results based on multi‐event models applied tag‐recovery data 700 sharks 132 makos tagged over a decade. A total 60 (8.57% tagged) 30 (22.73%) were recovered by longline fishery between 2009 2017. Tag‐reporting rate (percentage returned information when was caught) estimated be high (0.794 ± 0.232 SE). Mean annual as predicted from models, higher (0.835 0.040 SE) than (0.618 0.189 Models that caused more half study area both (0.576 0.209), third individuals dispersed permanently (0.359 0.073). findings, focused mainly areas, contribute better understanding dynamics highlight need further mako, such implementing efficient bycatch mitigation static/dynamic time–area closures open

Language: Английский

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Design and fabrication of a stereo-video camera equipped unoccupied aerial vehicle for measuring sea turtles, sharks, and other marine fauna

PLoS ONE, Journal Year: 2022, Volume and Issue: 17(10), P. e0276382 - e0276382

Published: Oct. 18, 2022

The recent commercialization of unoccupied aerial vehicles (UAVs) has facilitated their incorporation into a variety ecological studies. While UAVs are able to provide accurate visual data marine species from an perspective, these devices have some limitations that make measuring animals below the surface challenging. Many organisms often visible air, but deeper in water column, and current methods cannot measure surface. Here, we developed tested stereo-video camera (SVC) system was mounted onto commercially-available UAV. We used SVC-UAV conduct remote body-size measurements for two species: green sea turtle ( Chelonia mydas ) nurse shark Ginglymostoma cirratum ). When comparing SVC those taken by hand, had mean absolute error (MAE) 4.44 cm (n = 6; percent (MPE) 10.6%) turtles 7.16 1; PE 3.6%) shark. Using linear model, estimated slope versus hand be 1.085 (±0.099 SE), accounting standard error, measurement bias not apparent. model selection, based on global predicting MAE animal distance body size, top ranked intercept-only model. This indicates neither nor size strongly influenced error. Incorporating systems can allow relatively near surface-dwelling species. To our knowledge, there is no other stand-alone available offers similar accuracy utility.

Language: Английский

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First evidence of white sharks, Carcharodon carcharias, in the tongue of the ocean, central Bahamas

Frontiers in Marine Science, Journal Year: 2024, Volume and Issue: 11

Published: July 31, 2024

The white shark, Carcharodon carcharias , is an iconic apex predator, playing important ecological role across its range. Persistent bycatch and overfishing led to shark declines, but recent studies in the North Western Atlantic (NWA) revealed evidence for regional recovery, highlighted importance of Southeastern Florida Gulf Mexico as overwintering grounds maturing sharks. However, despite proximity comparably productive habitats, records sharks Bahamas are extremely rare, with a comprehensive survey sightings captures describing only one between 1800 - 2010. Here, we reveal acoustic tracking detections ten from 2020 2024 along western edge Tongue Ocean off Central Andros Island, Bahamas. White were originally tagged coast United States Canada, detected November-May. drop-off zone reef at ca. 25 m, exclusively dusk dawn, number suggesting transient behavior. These findings expand our knowledge distribution NWA, highlighting data gaps underlining collaborative protective measures species recovery.

Language: Английский

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Female wound records suggest mating periods for the Caribbean reef shark at an insular marine protected area from the Equatorial Atlantic Ocean

Journal of Fish Biology, Journal Year: 2022, Volume and Issue: 101(6), P. 1591 - 1594

Published: Sept. 7, 2022

Despite being one of the most abundant, economically significant, reef-associated shark species, little is known about reproductive aspects Caribbean reef (Carcharhinus perezi). In present study authors report first evidence mating wounds and scars in female sharks at Fernando de Noronha Archipelago, a remote marine protected area South Atlantic Ocean. Data from four females suggest this species mates mainly during austral summer, between February March. Given that archipelago has been previously described as nursery ground for shark, these results add information cycle equatorial

Language: Английский

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Shedding rates and retention performance of conventional dart tags in large pelagic sharks: Insights from a double-tagging experiment on blue shark (Prionace glauca)

Fisheries Research, Journal Year: 2022, Volume and Issue: 255, P. 106462 - 106462

Published: Aug. 17, 2022

Language: Английский

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Observations of biennial reproduction in Caribbean reef sharks ‘Carcharhinus perezi’

Frontiers in Marine Science, Journal Year: 2024, Volume and Issue: 10

Published: Jan. 11, 2024

Effective management and conservation of threatened species biodiversity requires knowledge reproductive biology, such as cyclicity, mode, age at maturity. We combined endocrinology in-situ ultrasonography to examine characteristics female Caribbean reef sharks Carcharhinus perezi , a widely distributed, marine predator which remains largely understudied throughout its range. Unique this study was the opportunity conduct longitudinal assessments two individuals, recaptured across multiple seasons during sampling in The Bahamas. Within-individual, paired hormone analyses ultrasounds that were confirmed either pregnant, non-pregnant, or reproductively active, suggest biennial cycle for . This unique assess biology same individuals over time underscore importance repeated elucidating population cyclicity highly mobile wild.

Language: Английский

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