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The Caribbean reef shark (Carcharhinus perezi) is an economically important species in The Bahamas, where it is protected from fishing and is a mainstay for the shark dive tourism industry. Significant declines in abundance are suspected throughout much of its range, making the study of its life history and spatial ecology important for effective fisheries management and conservation planning. We used tag-recapture data collected in The Bahamas between 2008 and 2020 to investigate the species' linear movements, population characteristics, life history, and growth. Sharks moved little between tag and recapture events (range: 0 to 8 km) despite multiple years at liberty for many sharks (range: 2 days to 7.1 years). We found no evidence of seasonal migration. We used a combined-sex von Bertalanffy growth function to estimate an asymptotic mean length at age (TL∞) of 205.8 cm total length and a growth coefficient (k) of 0.06. Theoretical maximum longevity was 43.3 to 57.8 years. Median male length at maturity (L50) was 148.9 cm total length (95% CI: 146.1–151.5 cm), which likely occurs around 14.8 years of age. Our results indicate slower growth of the Caribbean reef shark in The Bahamas than previously estimated in Venezuela. Our results suggest the Caribbean reef shark may be more vulnerable to overfishing and extirpation at the northern extent of its range than previously considered and that large no-take areas may be an effective conservation tool for this species. [ABSTRACT FROM AUTHOR]

The Caribbean reef shark (Carcharhinus perezi; Poey, 1876) is a medium to large-bodied coastal and reef-associated predator found throughout the subtropical and tropical waters of the Atlantic Ocean and Caribbean Sea, although its populations are increasingly threatened by overfishing. We describe the first mitochondrial genome sequence for this species, using Illumina MiSeq sequencing of an individual from The Bahamas. We report the mitogenome sequence of the Caribbean reef shark to be 16,709 bp and composed two rRNA genes, 22 tRNA genes, 13 protein-coding genes, 2 non-coding regions; the D-loop control region and the origin of light-strand replication. We discuss the implications of this new information on future monitoring efforts and conservation measures such as marine protected areas, and urge for greater application of mitochondrial studies of sharks in the Atlantic Ocean.

As ecotourists become increasingly interested in snorkeling and diving with sharks, it is important to establish directives for safe interactions. The study considered eye contact between humans and approaching sharks, examining specifically whether an interruption in it owing to, for example, a person glancing at a camera or regarding where to retreat, would affect a shark's behavior. In standardized field tests, divers maintained or interrupted eye contact with approaching Caribbean reef sharks, Carcharhinus perezi. The results showed a significant difference in the sharks' approaches depending on whether the divers maintained or interrupted eye contact with them. More specifically, the analysis revealed that sharks came significantly closer to the divers when eye contact was interrupted and also reduced their speed. [ABSTRACT FROM AUTHOR]

We investigated spatial use patterns of 77 Caribbean reef sharks (Carcharhinus perezi) at Lighthouse Reef Atoll, Belize over 7 years using residency patterns, kernel density (KD) estimation and network analysis. We found a high degree individual variation in spatial use of the atoll, but there were significant differences in residency and activity space between sexes, with females being overall more resident. Ontogenetic shifts in movement and residency were largely limited to females, as the residency index increased and activity space estimates decreased as females matured, while for males there was no relationship between space use or residency and size. KD analysis revealed many mature females were highly resident to discrete locations, and average activity space of the intermediate-sized sharks was significantly larger than that of the adults, but not the smallest sharks. Markov chain analyses indicated that the southwestern portion of the atoll was the most important movement corridor for all sharks. Both the Blue Hole and Half Moon Caye Natural Monuments provide some protection for larger Caribbean reef sharks; however, a gear ban on longlines on the southwestern forereef between Long Caye and the channel entrance to the Blue Hole would maximize the benefits for all sharks.

The Caribbean reef shark (Carcharhinus perezi; Poey, 1876) is a medium to large-bodied coastal and reef-associated predator found throughout the subtropical and tropical waters of the Atlantic Ocean and Caribbean Sea, although its populations are increasingly threatened by overfishing. We describe the first mitochondrial genome sequence for this species, using Illumina MiSeq sequencing of an individual from The Bahamas. We report the mitogenome sequence of the Caribbean reef shark to be 16,709 bp and composed two rRNA genes, 22 tRNA genes, 13 protein-coding genes, 2 non-coding regions; the D-loop control region and the origin of light-strand replication. We discuss the implications of this new information on future monitoring efforts and conservation measures such as marine protected areas, and urge for greater application of mitochondrial studies of sharks in the Atlantic Ocean. [ABSTRACT FROM AUTHOR]

Abstract: Longline fishing is the most common elasmobranch capture method around the world, yet the physiological consequences of this technique are poorly understood. To quantify the sub-lethal effects of longline capture in the commonly exploited Caribbean reef shark (Carcharhinus perezi), 37 individuals were captured using standard, mid-water longlines. Hook timers provided hooking duration to the nearest minute. Once sharks were landed, blood samples were taken and used to measure a suite of physiological parameters. Control data were obtained by sampling an additional three unrestrained Caribbean reef sharks underwater at an established shark feeding site. The greatest level of physiological disruption occurred after 120–180min of hooking, whereas sharks exposed to minimal and maximal hook durations exhibited the least disturbed blood chemistry. Significant relationships were established between hooking duration and blood pH, pCO2, lactate, glucose, plasma calcium and plasma potassium. Longline capture appears more benign than other methods assessed to date, causing a shift in the stress response from acute at the onset of capture to a sub-acute regime as the capture event progresses, apparently facilitating a degree of physiological recovery. Continued investigation into the physiological response of elasmobranchs to longline capture is vital for the effective management of such fisheries. [Copyright &y& Elsevier]

Mouth gaping in sharks has been considered to be either a threat display or a response to sharksucker irritation, but has never been examined in greater detail. Another form of gaping was observed frequently around feeding scenarios, primarily when sharks swam away from the food source. This form of a yawn-like behavior of Caribbean reef sharks, Carcharhinus perezi, was videotaped during both standard feeding and non-feeding scenarios, and examined for both proximate causation and function. This type of gaping reflects a simulated bite process, including all bite phases, but differs from actual bites in that the duration is as great as 10 times longer, with the expansion phase disproportionally prolonged and a pause at the gape's peak. Of all the possible functions discussed, a maintenance behavior to reposition the jaw elements after feeding fits all of the measured parameters. [ABSTRACT FROM AUTHOR]

The Caribbean reef shark ( Carcharhinus perezi; Poey, 1876) is a medium to large-bodied coastal and reef-associated predator found throughout the subtropical and tropical waters of the Atlantic Ocean and Caribbean Sea, although its populations are increasingly threatened by overfishing. We describe the first mitochondrial genome sequence for this species, using Illumina MiSeq sequencing of an individual from The Bahamas. We report the mitogenome sequence of the Caribbean reef shark to be 16,709 bp and composed two rRNA genes, 22 tRNA genes, 13 protein-coding genes, 2 non-coding regions; the D-loop control region and the origin of light-strand replication. We discuss the implications of this new information on future monitoring efforts and conservation measures such as marine protected areas, and urge for greater application of mitochondrial studies of sharks in the Atlantic Ocean., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)

We investigated spatial use patterns of 77 Caribbean reef sharks ( Carcharhinus perezi ) at Lighthouse Reef Atoll, Belize over 7 years using residency patterns, kernel density (KD) estimation and network analysis. We found a high degree individual variation in spatial use of the atoll, but there were significant differences in residency and activity space between sexes, with females being overall more resident. Ontogenetic shifts in movement and residency were largely limited to females, as the residency index increased and activity space estimates decreased as females matured, while for males there was no relationship between space use or residency and size. KD analysis revealed many mature females were highly resident to discrete locations, and average activity space of the intermediate-sized sharks was significantly larger than that of the adults, but not the smallest sharks. Markov chain analyses indicated that the southwestern portion of the atoll was the most important movement corridor for all sharks. Both the Blue Hole and Half Moon Caye Natural Monuments provide some protection for larger Caribbean reef sharks; however, a gear ban on longlines on the southwestern forereef between Long Caye and the channel entrance to the Blue Hole would maximize the benefits for all sharks., (© 2021 The Authors.)