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Auliya M, Rasmussen AR, Sanders KL, Lobo AS. Challenges of regulating commercial use of marine elapid snakes in the Indo-Pacific. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2024; 38:e14336. [PMID: 39248777 DOI: 10.1111/cobi.14336] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 09/27/2023] [Accepted: 10/25/2023] [Indexed: 09/10/2024]
Abstract
Marine elapid snakes are a diverse, predominantly Indo-West Pacific species group. The persistent removal of some species has an unquantified but potentially dire impact on populations. We conducted the first comprehensive review of the trade in marine elapid snakes based on published literature (1974-2022) and trade data from the only species (i.e., Hydrophis [Lapemis] curtus) whose trade is monitored internationally. Some species and populations were subjected to targeted harvest for their meat and skins for at least the last century; fisheries are possibly the most significant threat to populations of marine elapids, with the highest numbers being exploited either accidentally, incidentally, or opportunistically in Southeast Asian fisheries targeting other seafood, including demersal trawl and squid fisheries. Southeast Asia is the core region for exploitation of marine elapids. Annual offtake is >225,000 individuals of at least 8 species in the Gulf of Thailand. Of 72 recognized marine elapids (all non-CITES [Convention on International Trade in Endangered Species of Wild Fauna and Flora] species), Hydrophis curtus and Hydrophis cyanocinctus dominate the skin trade. Skins of H. curtus are traded mainly in East and Southeast Asia and, to some extent, Europe. Despite some baseline information on the trade of these species, the sustainability of their harvests, particularly in the context of the burgeoning and unmanaged nature of fisheries in the region, remains the major challenge. In an era of declining fish stocks, there has been an increasing trend to commercialize the harvest and use marine elapids that were once considered accidental bycatch and discarded. This trend will continue to pose a significant risk to these snakes unless appropriate fisheries and trade regulations are enforced. Applying the precautionary principle to prevent the overexploitation of sea snakes is an indispensable measure in which trade in regional populations should be regulated through CITES. Accordingly, management plans to identify core distribution regions of exploited species would be crucial for assigning national responsibilities to sustain species and populations in the long term.
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Affiliation(s)
- Mark Auliya
- Museum Alexander Koenig, The Leibniz Institute for the Analysis of Biodiversity Change, Bonn, Germany
| | | | - Kate L Sanders
- School of Biological Sciences, The University of Adelaide, Adelaide, South Australia, Australia
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Lowe C, Keppel G, Waqa K, Peters S, Fisher RN, Scanlon A, Osborne‐Naikatini T, Thomas‐Moko N. Fijian sea krait behavior relates to fine‐scale environmental heterogeneity in old‐growth coastal forest: The importance of integrated land–sea management for protecting amphibious animals. Ecol Evol 2022; 12:e8817. [PMID: 35475179 PMCID: PMC9022443 DOI: 10.1002/ece3.8817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 03/24/2022] [Accepted: 03/28/2022] [Indexed: 12/04/2022] Open
Abstract
The importance of terrestrial coastal ecosystems for maintaining healthy coral reef ecosystems remains understudied. Sea kraits are amphibious snakes that require healthy coral reefs for foraging, but little is known about their requirements of terrestrial habitats, where they slough their skin, digest prey, and breed. Using concurrent microclimate measurements and behavior surveys, we show that a small, topographically flat atoll in Fiji with coastal forest provides many microhabitats that relate to the behaviors of Yellow Lipped Sea Kraits, Laticauda colubrina. Microclimates were significantly related to canopy cover, leaf litter depth, and distance from the high‐water mark (HWM). Sea kraits were almost exclusively observed in coastal forest within 30 m of the HWM. Sloughing of skins only occurred within crevices of mature or dying trees. Resting L. colubrina were significantly more likely to occur at locations with higher mean diurnal temperatures, lower leaf litter depths, and shorter distances from the HWM. On Leleuvia, behavior of L. colubrina therefore relates to environmental heterogeneity created by old‐growth coastal forests, particularly canopy cover and crevices in mature and dead tree trunks. The importance of healthy coastal habitats, both terrestrial and marine, for L. colubrina suggests it could be a good flagship species for advocating integrated land‐sea management. Furthermore, our study highlights the importance of coastal forests and topographically flat atolls for biodiversity conservation. Effective conservation management of amphibious species that utilize land‐ and seascapes is therefore likely to require a holistic approach that incorporates connectivity among ecosystems and environmental heterogeneity at all relevant scales.
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Affiliation(s)
- Christopher Lowe
- UniSA STEM University of South Australia Adelaide South Australia Australia
| | - Gunnar Keppel
- UniSA STEM University of South Australia Adelaide South Australia Australia
- Future Industries Institute University of South Australia Adelaide South Australia Australia
| | | | - Stefan Peters
- UniSA STEM University of South Australia Adelaide South Australia Australia
| | - Robert N. Fisher
- NatureFiji‐MareqetiViti Suva Fiji
- U.S. Geological Survey Western Ecological Research Center San Diego California USA
| | - Annette Scanlon
- UniSA STEM University of South Australia Adelaide South Australia Australia
- Department of Primary Industries and Regions Government of South Australia Adelaide South Australia Australia
| | - Tamara Osborne‐Naikatini
- Faculty of Science, Technology and Environment School of Biological and Chemical Sciences The University of the South Pacific Suva Fiji
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Bonnet X, Brischoux F, Briand M, Shine R. Plasticity matches phenotype to local conditions despite genetic homogeneity across 13 snake populations. Proc Biol Sci 2021; 288:20202916. [PMID: 33499786 DOI: 10.1098/rspb.2020.2916] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
In a widespread species, a matching of phenotypic traits to local environmental optima is generally attributed to site-specific adaptation. However, the same matching can occur via adaptive plasticity, without requiring genetic differences among populations. Adult sea kraits (Laticauda saintgironsi) are highly philopatric to small islands, but the entire population within the Neo-Caledonian Lagoon is genetically homogeneous because females migrate to the mainland to lay their eggs at communal sites; recruits disperse before settling, mixing up alleles. Consequently, any matching between local environments (e.g. prey sizes) and snake phenotypes (e.g. body sizes and relative jaw sizes (RJSs)) must be achieved via phenotypic plasticity rather than spatial heterogeneity in gene frequencies. We sampled 13 snake colonies spread along an approximately 200 km northwest-southeast gradient (n > 4500 individuals) to measure two morphological features that affect maximum ingestible prey size in gape-limited predators: body size and RJS. As proxies of habitat quality (HQ), we used protection status, fishing pressure and lagoon characteristics (lagoon width and distance of islands to the barrier reef). In both sexes, spatial variation in body sizes and RJSs was linked to HQ; albeit in different ways, consistent with sex-based divergences in foraging ecology. Strong spatial divergence in morphology among snake colonies, despite genetic homogeneity, supports the idea that phenotypic plasticity can facilitate speciation by creating multiple phenotypically distinct subpopulations shaped by their environment.
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Affiliation(s)
- Xavier Bonnet
- CEBC, UMR 7372 CNRS and University of La Rochelle, 79360 Villiers en Bois, France
| | - François Brischoux
- CEBC, UMR 7372 CNRS and University of La Rochelle, 79360 Villiers en Bois, France
| | | | - Richard Shine
- Department of Biological Sciences, Macquarie University, New South Wales 2109, Australia
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Arsovski D, Tomović L, Golubović A, Nikolić S, Sterijovski B, Ajtić R, Ballouard JM, Bonnet X. When carapace governs size: variation among age classes and individuals in a free-ranging ectotherm with delayed maturity. Oecologia 2018; 186:953-963. [PMID: 29480451 DOI: 10.1007/s00442-018-4090-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 02/08/2018] [Indexed: 10/17/2022]
Abstract
Juvenile growth strongly impacts life-history traits during adulthood. Yet, in juveniles with delayed maturity, elusiveness has hindered age-specific studies of growth, precluding any detailed research on its consequences later in life. Different complex growth patterns have been extracted from captive animals, suggesting species-specific trajectories occur in free-ranging animals. How pronounced are growth and body size variation (VBS) throughout a long-lived ectotherm's life? Is VBS constant among age classes prior to maturity, or do compensatory and/or cumulative effects driven by long-lived-animal-specific strategies create distinct VBS cohorts, to ensure survival? To tackle the issue, we modelled growth data from continuous and dense annual capture-mark-recapture sampling (5096 body measurements of 1134 free-ranging individuals) of both immature and mature, long-lived Hermann's tortoises. We analysed population, cohort, and individual-based growth and VBS. Growth ring inferred ages were cross validated with annual recaptures in 289 juveniles. Analyses unravelled an S-shaped growth curve and identified three age cohorts across which VBS increases in a step-wise manner. Neonate-specific constraints and compensatory effects seem to control VBS until 4 years of age, possibly promoting survival with size. Subsequently, a hardened carapace takes over and cumulative effects fuelled by faster growth progressively increase VBS. Whereas ungulates are in a hurry to attain adult size before growth ceases (minimizing VBS), indeterminately growing tortoises can shape individual asymptotic sizes even after growth decelerates. Tortoise size is clearly shaped by age-specific ecological constraints; interestingly, it is likely the carapace that conducts the strategy, rather than maturity per se.
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Affiliation(s)
- Dragan Arsovski
- CEBC, UMR-7372, CNRS ULR, 79360, Villiers en Bois, France. .,Macedonian Ecological Society, Bulevar "Kuzman Josifovski-Pitu" 28/3-7, 1000, Skopje, Macedonia.
| | - Ljiljana Tomović
- Faculty of Biology, Institute of Zoology, University of Belgrade, Studentski trg 16, 11000, Belgrade, Serbia
| | - Ana Golubović
- Faculty of Biology, Institute of Zoology, University of Belgrade, Studentski trg 16, 11000, Belgrade, Serbia
| | - Sonja Nikolić
- Faculty of Biology, Institute of Zoology, University of Belgrade, Studentski trg 16, 11000, Belgrade, Serbia
| | - Bogoljub Sterijovski
- Macedonian Ecological Society, Bulevar "Kuzman Josifovski-Pitu" 28/3-7, 1000, Skopje, Macedonia
| | - Rastko Ajtić
- Institute for Nature Conservation of Serbia, Dr Ivana Ribara 91, 11070, Belgrade, Serbia
| | - Jean-Marie Ballouard
- Station d'Observation et de Protection des Tortues et de leurs Milieux (SOPTOM), B.P. 24, 83590, Gonfaron, France
| | - Xavier Bonnet
- CEBC, UMR-7372, CNRS ULR, 79360, Villiers en Bois, France
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Tabata R, Tashiro F, Nishizawa H, Takagi J, Kidera N, Mitamura H. Stomach Contents of Three Sea Kraits (Hydrophiinae: Laticauda spp.) in the Ryukyu Islands, Japan. CURRENT HERPETOLOGY 2017. [DOI: 10.5358/hsj.36.127] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Runa Tabata
- Graduate School of Informatics, Kyoto University, Sakyo, Kyoto, Kyoto 606-8501, JAPAN
| | - Fumihito Tashiro
- Maizuru Fisheries Research Station, Field Science Education and Research Center, Kyoto University, Maizuru, Kyoto 625-0086, JAPAN
| | - Hideaki Nishizawa
- Graduate School of Informatics, Kyoto University, Sakyo, Kyoto, Kyoto 606-8501, JAPAN
| | - Junichi Takagi
- Graduate School of Informatics, Kyoto University, Sakyo, Kyoto, Kyoto 606-8501, JAPAN
| | - Noriko Kidera
- National Institute for Environmental Studies, Tsukuba, Ibaraki 305-8506, JAPAN
| | - Hiromichi Mitamura
- Graduate School of Informatics, Kyoto University, Sakyo, Kyoto, Kyoto 606-8501, JAPAN
- CREST, Japan Science and Technology Agency, Kawaguchi, Saitama 102-0076, JAPAN
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Udyawer V, Simpfendorfer CA, Heupel MR, Clark TD. Temporal and spatial activity‐associated energy partitioning in free‐swimming sea snakes. Funct Ecol 2017. [DOI: 10.1111/1365-2435.12882] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Vinay Udyawer
- Australian Institute of Marine Science Townsville QLD4810 Australia
- Centre for Sustainable Tropical Fisheries and Aquaculture & College of Science and Engineering James Cook University Townsville QLD4811 Australia
| | - Colin A. Simpfendorfer
- Centre for Sustainable Tropical Fisheries and Aquaculture & College of Science and Engineering James Cook University Townsville QLD4811 Australia
| | - Michelle R. Heupel
- Australian Institute of Marine Science Townsville QLD4810 Australia
- Centre for Sustainable Tropical Fisheries and Aquaculture & College of Science and Engineering James Cook University Townsville QLD4811 Australia
| | - Timothy D. Clark
- Australian Institute of Marine Science Townsville QLD4810 Australia
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Importance of Shallow Tidal Habitats as Refugia from Trawl Fishing for Sea Snakes. J HERPETOL 2016. [DOI: 10.1670/15-026] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Bonnet X, Brischoux F, Pinaud D, Michel CL, Clobert J, Shine R, Fauvel T. Spatial variation in age structure among colonies of a marine snake: the influence of ectothermy. J Anim Ecol 2015; 84:925-33. [PMID: 25785869 DOI: 10.1111/1365-2656.12358] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 02/06/2015] [Indexed: 11/27/2022]
Affiliation(s)
- Xavier Bonnet
- Centre d'Etudes Biologiques de Chizé; UMR 7372-CNRS Université de La Rochelle; Villiers-en-Bois 79360 France
| | - François Brischoux
- Centre d'Etudes Biologiques de Chizé; UMR 7372-CNRS Université de La Rochelle; Villiers-en-Bois 79360 France
| | - David Pinaud
- Centre d'Etudes Biologiques de Chizé; UMR 7372-CNRS Université de La Rochelle; Villiers-en-Bois 79360 France
| | - Catherine Louise Michel
- Centre d'Etudes Biologiques de Chizé; UMR 7372-CNRS Université de La Rochelle; Villiers-en-Bois 79360 France
| | - Jean Clobert
- Station d'Ecologie Expérimentale du CNRS à Moulis USR 2936; Moulis Saint-Girons 09200 France
| | - Richard Shine
- School of Biological Sciences A08; University of Sydney; Sydney NSW 2006 Australia
| | - Thomas Fauvel
- Centre d'Etudes Biologiques de Chizé; UMR 7372-CNRS Université de La Rochelle; Villiers-en-Bois 79360 France
- Université Pierre et Marie Curie; Paris 75005 France
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