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Camins E, Stanton LM, Correia M, Foster SJ, Koldewey HJ, Vincent ACJ. Advances in life-history knowledge for 35 seahorse species from community science. J Fish Biol 2024. [PMID: 38408838 DOI: 10.1111/jfb.15699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 01/26/2024] [Accepted: 02/09/2024] [Indexed: 02/28/2024]
Abstract
Marine community science presents an important route to gather valuable scientific information while also influencing local management and policy, thus contributing to marine conservation efforts. Because seahorses are cryptic but charismatic species, they are good candidates for engaging diverse people to help overcome the many gaps in biological knowledge. We have synthesized information contributed to the community science project iSeahorse from October 2013 to April 2022 for 35 of 46 known seahorse species. We then compared the obtained results with information in existing IUCN Red List assessments, executed from 2014 to 2017, to explore the potential of iSeahorse in expanding seahorse knowledge. Our results show updated geographic ranges for 7 seahorse species, new habitats described for 24 species, observations outside the previously recorded depth range for 14 species, and new information on sex ratio for 15 species and on pregnancy seasonality for 11 species. As one example of the power of iSeahorse, contributed observations on Coleman's pygmy seahorse (Hippocampus colemani) indicated that its geographic range is thousands of square kilometers larger, its habitat more diverse, and its depth range shallower than previously known. It is clear that iSeahorse is expanding knowledge on seahorses to a level that will help improve IUCN Red List assessments. The power of community science for marine conservation in general needs to be fully explored.
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Affiliation(s)
- Elsa Camins
- Project Seahorse, Institute for the Oceans and Fisheries, The University of British Columbia, Vancouver, British Columbia, Canada
- Seahorse, Pipefish, and Seadragon Specialist Group, IUCN Species Survival Commission, Gland, Switzerland
| | - Lily M Stanton
- Project Seahorse, Institute for the Oceans and Fisheries, The University of British Columbia, Vancouver, British Columbia, Canada
- Seahorse, Pipefish, and Seadragon Specialist Group, IUCN Species Survival Commission, Gland, Switzerland
| | - Miguel Correia
- Project Seahorse, Institute for the Oceans and Fisheries, The University of British Columbia, Vancouver, British Columbia, Canada
- Seahorse, Pipefish, and Seadragon Specialist Group, IUCN Species Survival Commission, Gland, Switzerland
| | - Sarah J Foster
- Project Seahorse, Institute for the Oceans and Fisheries, The University of British Columbia, Vancouver, British Columbia, Canada
- Seahorse, Pipefish, and Seadragon Specialist Group, IUCN Species Survival Commission, Gland, Switzerland
| | - Heather J Koldewey
- Seahorse, Pipefish, and Seadragon Specialist Group, IUCN Species Survival Commission, Gland, Switzerland
- Project Seahorse, Zoological Society of London, Regent's Park, London, UK
| | - Amanada C J Vincent
- Project Seahorse, Institute for the Oceans and Fisheries, The University of British Columbia, Vancouver, British Columbia, Canada
- Seahorse, Pipefish, and Seadragon Specialist Group, IUCN Species Survival Commission, Gland, Switzerland
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2
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Napper IE, Davies AJ, Jah M, Miner KR, Thompson RC, Quinn M, Koldewey HJ. Protect Earth's orbit: Avoid high seas mistakes. Science 2023; 379:990-991. [PMID: 36893228 DOI: 10.1126/science.adg8989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
Affiliation(s)
- Imogen E Napper
- International Marine Litter Research Unit, University of Plymouth, Plymouth, PL4 8AA, UK
| | | | - Moriba Jah
- Oden Institute for Computational Engineering and Sciences, The University of Texas at Austin, Austin, TX, USA
| | - Kimberley R Miner
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Richard C Thompson
- International Marine Litter Research Unit, University of Plymouth, Plymouth, PL4 8AA, UK
| | - Melissa Quinn
- Spaceport Cornwall, Cornwall Airport Newquay, Newquay TR8 4RQ, UK
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3
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Ford HV, Jones NH, Davies AJ, Godley BJ, Jambeck JR, Napper IE, Suckling CC, Williams GJ, Woodall LC, Koldewey HJ. The fundamental links between climate change and marine plastic pollution. Sci Total Environ 2022; 806:150392. [PMID: 34583073 DOI: 10.1016/j.scitotenv.2021.150392] [Citation(s) in RCA: 57] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 08/27/2021] [Accepted: 09/13/2021] [Indexed: 05/25/2023]
Abstract
Plastic pollution and climate change have commonly been treated as two separate issues and sometimes are even seen as competing. Here we present an alternative view that these two issues are fundamentally linked. Primarily, we explore how plastic contributes to greenhouse gas (GHG) emissions from the beginning to the end of its life cycle. Secondly, we show that more extreme weather and floods associated with climate change, will exacerbate the spread of plastic in the natural environment. Finally, both issues occur throughout the marine environment, and we show that ecosystems and species can be particularly vulnerable to both, such as coral reefs that face disease spread through plastic pollution and climate-driven increased global bleaching events. A Web of Science search showed climate change and plastic pollution studies in the ocean are often siloed, with only 0.4% of the articles examining both stressors simultaneously. We also identified a lack of regional and industry-specific life cycle analysis data for comparisons in relative GHG contributions by materials and products. Overall, we suggest that rather than debate over the relative importance of climate change or marine plastic pollution, a more productive course would be to determine the linking factors between the two and identify solutions to combat both crises.
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Affiliation(s)
- Helen V Ford
- School of Ocean Sciences, Bangor University, Anglesey LL59 5AB, UK.
| | - Nia H Jones
- School of Ocean Sciences, Bangor University, Anglesey LL59 5AB, UK
| | - Andrew J Davies
- Biological Sciences, University of Rhode Island, 120 Flagg Road University of Rhode Island Kingston, RI 02881, USA
| | - Brendan J Godley
- Centre for Ecology and Conservation, University of Exeter, Penryn, Cornwall, TR10 9FE, UK
| | - Jenna R Jambeck
- College of Engineering, University of Georgia, GA 30602, Athens, USA
| | - Imogen E Napper
- International Marine Litter Research Unit, School of Biological and Marine Sciences University of Plymouth, Plymouth PL4 8AA, UK
| | - Coleen C Suckling
- Fisheries, Animal and Veterinary Sciences, University of Rhode Island, Kingston, RI 02881, USA
| | | | - Lucy C Woodall
- Department of Zoology, University of Oxford, Oxford OX1 3SZ, UK; Nekton, Science Park, Begbroke, Oxford, OX5 1PF, UK
| | - Heather J Koldewey
- Centre for Ecology and Conservation, University of Exeter, Penryn, Cornwall, TR10 9FE, UK; Zoological Society of London, Regent's Park, London, UK
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4
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Pettorelli N, Graham NAJ, Seddon N, Maria da Cunha Bustamante M, Lowton MJ, Sutherland WJ, Koldewey HJ, Prentice HC, Barlow J. Time to integrate global climate change and biodiversity science‐policy agendas. J Appl Ecol 2021. [DOI: 10.1111/1365-2664.13985] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | | | - Nathalie Seddon
- Nature‐based Solutions Initiative Department of Zoology University of Oxford Oxford UK
| | | | | | - William J. Sutherland
- Department of Zoology Cambridge University Cambridge UK
- BioRISC (Biosecurity Research Initiative at St Catharine’s) St Catharine’s College Cambridge UK
| | - Heather J. Koldewey
- Conservation and Policy Zoological Society of London London UK
- Centre for Ecology and Conservation University of Exeter Penryn UK
| | | | - Jos Barlow
- Lancaster Environment Centre Lancaster University Lancaster UK
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5
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Carr P, Trevail A, Bárrios S, Clubbe C, Freeman R, Koldewey HJ, Votier SC, Wilkinson T, Nicoll MAC. Potential benefits to breeding seabirds of converting abandoned coconut plantations to native habitats after invasive predator eradication. Restor Ecol 2021. [DOI: 10.1111/rec.13386] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Peter Carr
- Institute of Zoology Zoological Society of London, Regent's Park London NW1 4RY U.K
- Environment and Sustainability Institute, Centre for Ecology and Conservation University of Exeter, Penryn Campus Cornwall TR10 9EZ U.K
| | - Alice Trevail
- Environment and Sustainability Institute, Centre for Ecology and Conservation University of Exeter, Penryn Campus Cornwall TR10 9EZ U.K
| | - Sara Bárrios
- Conservation Science Royal Botanic Gardens, Kew London TW9 3AE U.K
| | - Colin Clubbe
- Conservation Science Royal Botanic Gardens, Kew London TW9 3AE U.K
| | - Robin Freeman
- Institute of Zoology Zoological Society of London, Regent's Park London NW1 4RY U.K
| | - Heather J. Koldewey
- Institute of Zoology Zoological Society of London, Regent's Park London NW1 4RY U.K
- Environment and Sustainability Institute, Centre for Ecology and Conservation University of Exeter, Penryn Campus Cornwall TR10 9EZ U.K
| | - Stephen C. Votier
- Environment and Sustainability Institute, Centre for Ecology and Conservation University of Exeter, Penryn Campus Cornwall TR10 9EZ U.K
- School of Energy, Geoscience, Infrastructure and Society Heriot‐Watt University Edinburgh EH14 4AS U.K
| | - Tim Wilkinson
- Conservation Science Royal Botanic Gardens, Kew London TW9 3AE U.K
| | - Malcolm A. C. Nicoll
- Institute of Zoology Zoological Society of London, Regent's Park London NW1 4RY U.K
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6
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Chowdhury GW, Koldewey HJ, Duncan E, Napper IE, Niloy MNH, Nelms SE, Sarker S, Bhola S, Nishat B. Plastic pollution in aquatic systems in Bangladesh: A review of current knowledge. Sci Total Environ 2021; 761:143285. [PMID: 33172641 DOI: 10.1016/j.scitotenv.2020.143285] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 10/03/2020] [Accepted: 10/21/2020] [Indexed: 06/11/2023]
Abstract
Rivers play a crucial role in transporting land-based plastic waste to the ocean, with the Ganges reported as the second largest contributing river of plastic pollution globally. To better quantify global plastic pollution transport and effectively reduce the sources and risks imposed, a clear understanding of the origin, transport, fate, and effects of riverine plastic debris is important. In this review paper, we discuss the current state of knowledge of plastic pollution in aquatic systems in Bangladesh and evaluate existing research gaps. Bangladesh has been recognized as an internationally significant nation in the plastic pollution crisis, but this paper identifies a major disconnect in knowledge, understanding and capacity to understand and address this critical environmental and public health issue. Here, we review all available scientific publications on plastic pollution in the freshwater and marine environment in Bangladesh and identify key research themes. A total of 24 studies relevant to plastic pollution were published from 2006 to 2019, of which 18 were selected for this study under the authors' criteria. Nine focused on plastic pollution in the marine environment, eight focused on plastic waste generation and management and only one focused on the freshwater environment. We compared our findings with three other countries in the Global South with comparable per capita gross domestic product (GDP) and mismanaged waste, namely Cambodia, Kenya, and Tanzania, revealing similar knowledge gaps. This lack of research demonstrates a need for further work to monitor and model riverine plastic transport and examine the implications for aquatic organisms. This will facilitate the formulation of national management strategies aimed at addressing plastic pollution.
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Affiliation(s)
- Gawsia Wahidunnessa Chowdhury
- Department of Zoology, University of Dhaka, Dhaka 1000, Bangladesh; WildTeam, 69/1 New Circular Road, Malibagh, Dhaka 1217, Bangladesh.
| | - Heather J Koldewey
- Zoological Society of London, Regent's Park, London NW1 4RY, UK; Centre for Ecology and Conservation, University of Exeter, Cornwall TR10 9EZ, UK
| | - Emily Duncan
- Centre for Ecology and Conservation, University of Exeter, Cornwall TR10 9EZ, UK
| | - Imogen E Napper
- International Marine Litter Research Unit, University of Plymouth, Plymouth PL4 8AA, UK
| | - Md Nazmul Hasan Niloy
- Department of Zoology, University of Dhaka, Dhaka 1000, Bangladesh; WildTeam, 69/1 New Circular Road, Malibagh, Dhaka 1217, Bangladesh
| | - Sarah E Nelms
- Centre for Ecology and Conservation, University of Exeter, Cornwall TR10 9EZ, UK; Centre for Circular Economy, University of Exeter, Cornwall TR10 9EZ, UK
| | - Subrata Sarker
- WildTeam, 69/1 New Circular Road, Malibagh, Dhaka 1217, Bangladesh; Department of Oceanography, Shahjalal University of Science and Technology, Sylhet 3114, Bangladesh
| | - Sunanda Bhola
- Wildlife Institute of India, Wildlife Institute Rd, Chandrabani, Dehradun, Uttarakhand 248002, India
| | - Bushra Nishat
- Isabela Foundation, House-13, Road-15 (new) 28 (old), Dhanmondi R/A, Dhaka 1209, Bangladesh; The World Bank, Plot # E-32 Agargaon, Sher-e-Bangla Nagar, Dhaka 1207, Bangladesh
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7
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Perez‐Correa J, Carr P, Meeuwig JJ, Koldewey HJ, Letessier TB. Climate oscillation and the invasion of alien species influence the oceanic distribution of seabirds. Ecol Evol 2020; 10:9339-9357. [PMID: 32953065 PMCID: PMC7487247 DOI: 10.1002/ece3.6621] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 06/30/2020] [Accepted: 07/09/2020] [Indexed: 12/29/2022] Open
Abstract
Spatial and temporal distribution of seabird transiting and foraging at sea is an important consideration for marine conservation planning. Using at-sea observations of seabirds (n = 317), collected during the breeding season from 2012 to 2016, we built boosted regression tree (BRT) models to identify relationships between numerically dominant seabird species (red-footed booby, brown noddy, white tern, and wedge-tailed shearwater), geomorphology, oceanographic variability, and climate oscillation in the Chagos Archipelago. We documented positive relationships between red-footed booby and wedge-tailed shearwater abundance with the strength in the Indian Ocean Dipole, as represented by the Dipole Mode Index (6.7% and 23.7% contribution, respectively). The abundance of red-footed boobies, brown noddies, and white terns declined abruptly with greater distance to island (17.6%, 34.1%, and 41.1% contribution, respectively). We further quantified the effects of proximity to rat-free and rat-invaded islands on seabird distribution at sea and identified breaking point distribution thresholds. We detected areas of increased abundance at sea and habitat use-age under a scenario where rats are eradicated from invaded nearby islands and recolonized by seabirds. Following rat eradication, abundance at sea of red-footed booby, brown noddy, and white terns increased by 14%, 17%, and 3%, respectively, with no important increase detected for shearwaters. Our results have implication for seabird conservation and island restoration. Climate oscillations may cause shifts in seabird distribution, possibly through changes in regional productivity and prey distribution. Invasive species eradications and subsequent island recolonization can lead to greater access for seabirds to areas at sea, due to increased foraging or transiting through, potentially leading to distribution gains and increased competition. Our approach predicting distribution after successful eradications enables anticipatory threat mitigation in these areas, minimizing competition between colonies and thereby maximizing the risk of success and the conservation impact of eradication programs.
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Affiliation(s)
- Julian Perez‐Correa
- Zoological Society of LondonInstitute of ZoologyLondonUK
- Escuela de Ciencias AmbientalesFacultad de IngenieríaUniversidad Espíritu SantoSamborondónEcuador
- Imperial College LondonLondonUK
| | - Peter Carr
- Zoological Society of LondonInstitute of ZoologyLondonUK
- Centre for Ecology and ConservationUniversity of ExeterCornwallUK
| | - Jessica J. Meeuwig
- Centre for Marine Futures, Oceans Institute and School of Animal BiologyThe University of Western AustraliaCrawleyWAAustralia
| | - Heather J. Koldewey
- Centre for Ecology and ConservationUniversity of ExeterCornwallUK
- Conservation and PolicyZoological Society of LondonLondonUK
| | - Tom B. Letessier
- Zoological Society of LondonInstitute of ZoologyLondonUK
- Centre for Marine Futures, Oceans Institute and School of Animal BiologyThe University of Western AustraliaCrawleyWAAustralia
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8
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Letessier TB, Mouillot D, Bouchet PJ, Vigliola L, Fernandes MC, Thompson C, Boussarie G, Turner J, Juhel JB, Maire E, Caley MJ, Koldewey HJ, Friedlander A, Sala E, Meeuwig JJ. Correction: Remote reefs and seamounts are the last refuges for marine predators across the Indo-Pacific. PLoS Biol 2019; 17:e3000489. [PMID: 31525181 PMCID: PMC6746354 DOI: 10.1371/journal.pbio.3000489] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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9
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Letessier TB, Mouillot D, Bouchet PJ, Vigliola L, Fernandes MC, Thompson C, Boussarie G, Turner J, Juhel JB, Maire E, Caley MJ, Koldewey HJ, Friedlander A, Sala E, Meeuwig JJ. Remote reefs and seamounts are the last refuges for marine predators across the Indo-Pacific. PLoS Biol 2019; 17:e3000366. [PMID: 31386657 PMCID: PMC6684043 DOI: 10.1371/journal.pbio.3000366] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 07/03/2019] [Indexed: 11/18/2022] Open
Abstract
Since the 1950s, industrial fisheries have expanded globally, as fishing vessels are required to travel further afield for fishing opportunities. Technological advancements and fishery subsidies have granted ever-increasing access to populations of sharks, tunas, billfishes, and other predators. Wilderness refuges, defined here as areas beyond the detectable range of human influence, are therefore increasingly rare. In order to achieve marine resources sustainability, large no-take marine protected areas (MPAs) with pelagic components are being implemented. However, such conservation efforts require knowledge of the critical habitats for predators, both across shallow reefs and the deeper ocean. Here, we fill this gap in knowledge across the Indo-Pacific by using 1,041 midwater baited videos to survey sharks and other pelagic predators such as rainbow runner (Elagatis bipinnulata), mahi-mahi (Coryphaena hippurus), and black marlin (Istiompax indica). We modeled three key predator community attributes: vertebrate species richness, mean maximum body size, and shark abundance as a function of geomorphology, environmental conditions, and human pressures. All attributes were primarily driven by geomorphology (35%-62% variance explained) and environmental conditions (14%-49%). While human pressures had no influence on species richness, both body size and shark abundance responded strongly to distance to human markets (12%-20%). Refuges were identified at more than 1,250 km from human markets for body size and for shark abundance. These refuges were identified as remote and shallow seabed features, such as seamounts, submerged banks, and reefs. Worryingly, hotpots of large individuals and of shark abundance are presently under-represented within no-take MPAs that aim to effectively protect marine predators, such as the British Indian Ocean Territory. Population recovery of predators is unlikely to occur without strategic placement and effective enforcement of large no-take MPAs in both coastal and remote locations.
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Affiliation(s)
- Tom B. Letessier
- Institute of Zoology, Zoological Society of London, London, United Kingdom
- School of Biological Sciences and The UWA Oceans Institute, University of Western Australia, (M092), Crawley, Australia
- * E-mail:
| | - David Mouillot
- MARBEC, Univ. Montpellier, CNRS, Ifremer, IRD, Montpellier, France
| | - Phil J. Bouchet
- School of Biological Sciences and The UWA Oceans Institute, University of Western Australia, (M092), Crawley, Australia
- School of Ocean Sciences, Bangor University, Menai Bridge, Wales
| | - Laurent Vigliola
- Institut de Recherche pour le Développement, UMR ENTROPIE, LABEX Corail, Nouméa, New Caledonia
| | - Marjorie C. Fernandes
- School of Biological Sciences and The UWA Oceans Institute, University of Western Australia, (M092), Crawley, Australia
| | - Chris Thompson
- School of Biological Sciences and The UWA Oceans Institute, University of Western Australia, (M092), Crawley, Australia
| | - Germain Boussarie
- School of Biological Sciences and The UWA Oceans Institute, University of Western Australia, (M092), Crawley, Australia
- MARBEC, Univ. Montpellier, CNRS, Ifremer, IRD, Montpellier, France
- Institut de Recherche pour le Développement, UMR ENTROPIE, LABEX Corail, Nouméa, New Caledonia
| | - Jemma Turner
- School of Biological Sciences and The UWA Oceans Institute, University of Western Australia, (M092), Crawley, Australia
| | - Jean-Baptiste Juhel
- MARBEC, Univ. Montpellier, CNRS, Ifremer, IRD, Montpellier, France
- Institut de Recherche pour le Développement, UMR ENTROPIE, LABEX Corail, Nouméa, New Caledonia
- Université de la Nouvelle-Calédonie, BPR4, Noumea, New Caledonia
| | - Eva Maire
- MARBEC, Univ. Montpellier, CNRS, Ifremer, IRD, Montpellier, France
| | - M. Julian Caley
- School of Mathematical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
- Australian Research Council Centre of Excellence for Mathematical and Statistical Frontiers, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Heather J. Koldewey
- Centre for Ecology & Conservation, University of Exeter, Penryn Campus, Penryn, Cornwall, United Kingdom
- Conservation Programmes, Zoological Society of London, London, United Kingdom
| | - Alan Friedlander
- Pristine Seas, National Geographic Society, Washington, DC, United States of America
- Fisheries Ecology Research Lab, University of Hawaii, Honolulu, Hawaii, United States of America
| | - Enric Sala
- Pristine Seas, National Geographic Society, Washington, DC, United States of America
| | - Jessica J. Meeuwig
- School of Biological Sciences and The UWA Oceans Institute, University of Western Australia, (M092), Crawley, Australia
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Duncan C, Owen HJF, Thompson JR, Koldewey HJ, Primavera JH, Pettorelli N. Satellite remote sensing to monitor mangrove forest resilience and resistance to sea level rise. Methods Ecol Evol 2018. [DOI: 10.1111/2041-210x.12923] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Clare Duncan
- Centre for Integrative Ecology School of Life and Environmental Sciences Deakin University Burwood Victoria Australia
- Institute of Zoology Zoological Society of London London UK
- UCL Department of Geography University College London London UK
| | | | | | - Heather J. Koldewey
- Conservation Programmes Zoological Society of London London UK
- Centre for Ecology and Conservation University of Exeter Penryn Cornwall UK
| | - Jurgenne H. Primavera
- Conservation Programmes Zoological Society of London London UK
- Zoological Society of London‐Philippines Iloilo City Philippines
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11
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Woodall LC, Otero-Ferrer F, Correia M, Curtis JMR, Garrick-Maidment N, Shaw PW, Koldewey HJ. A synthesis of European seahorse taxonomy, population structure, and habitat use as a basis for assessment, monitoring and conservation. Mar Biol 2017; 165:19. [PMID: 29238097 PMCID: PMC5717113 DOI: 10.1007/s00227-017-3274-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 11/22/2017] [Indexed: 06/07/2023]
Abstract
Accurate taxonomy, population demography, and habitat descriptors inform species threat assessments and the design of effective conservation measures. Here we combine published studies with new genetic, morphological and habitat data that were collected from seahorse populations located along the European and North African coastlines to help inform management decisions for European seahorses. This study confirms the presence of only two native seahorse species (Hippocampus guttulatus and H. hippocampus) across Europe, with sporadic occurrence of non-native seahorse species in European waters. For the two native species, our findings demonstrate that highly variable morphological characteristics, such as size and presence or number of cirri, are unreliable for distinguishing species. Both species exhibit sex dimorphism with females being significantly larger. Across its range, H. guttulatus were larger and found at higher densities in cooler waters, and individuals in the Black Sea were significantly smaller than in other populations. H. hippocampus were significantly larger in Senegal. Hippocampus guttulatus tends to have higher density populations than H. hippocampus when they occur sympatrically. Although these species are often associated with seagrass beds, data show both species inhabit a wide variety of shallow habitats and use a mixture of holdfasts. We suggest an international mosaic of protected areas focused on multiple habitat types as the first step to successful assessment, monitoring and conservation management of these Data Deficient species.
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Affiliation(s)
- Lucy C. Woodall
- Department of Zoology, University of Oxford, Oxford, UK
- Project Seahorse, Zoological Society of London, Regent’s Park, London, UK
| | - Francisco Otero-Ferrer
- Grupo en Biodiversidad y Conservación, IU-ECOAQUA, Universidad de Las Palmas de Gran Canaria, Crta. Taliarte s/n, 35214 Telde, Spain
| | - Miguel Correia
- Project Seahorse, Zoological Society of London, Regent’s Park, London, UK
- CCMar, Universidade do Algarve, F. C. T., Edificio 7, Campus de Gambelas, 8005-139 Faro, Portugal
| | - Janelle M. R. Curtis
- Pacific Biological Station, Fisheries and Oceans Canada, 3190 Hammond Bay Road, Nanaimo, BC Canada
| | | | - Paul W. Shaw
- Institute of Biological, Environmental and Rural Sciences (IBERS), Aberystwyth University, Aberystwyth, UK
| | - Heather J. Koldewey
- Project Seahorse, Zoological Society of London, Regent’s Park, London, UK
- Centre for Ecology and Conservation, University of Exeter, Penryn, UK
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12
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Tickler DM, Letessier TB, Koldewey HJ, Meeuwig JJ. Correction: Drivers of abundance and spatial distribution of reef-associated sharks in an isolated atoll reef system. PLoS One 2017; 12:e0186560. [PMID: 29023531 PMCID: PMC5638561 DOI: 10.1371/journal.pone.0186560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
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13
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Tickler DM, Letessier TB, Koldewey HJ, Meeuwig JJ. Drivers of abundance and spatial distribution of reef-associated sharks in an isolated atoll reef system. PLoS One 2017; 12:e0177374. [PMID: 28562602 PMCID: PMC5451018 DOI: 10.1371/journal.pone.0177374] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 04/26/2017] [Indexed: 11/18/2022] Open
Abstract
We investigated drivers of reef shark demography across a large and isolated marine protected area, the British Indian Ocean Territory Marine Reserve, using stereo baited remote underwater video systems. We modelled shark abundance against biotic and abiotic variables at 35 sites across the reserve and found that the biomass of low trophic order fish (specifically planktivores) had the greatest effect on shark abundance, although models also included habitat variables (depth, coral cover and site type). There was significant variation in the composition of the shark assemblage at different atolls within the reserve. In particular, the deepest habitat sampled (a seamount at 70-80m visited for the first time in this study) recorded large numbers of scalloped hammerhead sharks (Sphyrna lewini) not observed elsewhere. Size structure of the most abundant and common species, grey reef sharks (Carcharhinus amblyrhynchos), varied with location. Individuals at an isolated bank were 30% smaller than those at the main atolls, with size structure significantly biased towards the size range for young of year (YOY). The 18 individuals judged to be YOY represented the offspring of between four and six females, so, whilst inconclusive, these data suggest the possible use of a common pupping site by grey reef sharks. The importance of low trophic order fish biomass (i.e. potential prey) in predicting spatial variation in shark abundance is consistent with other studies both in marine and terrestrial systems which suggest that prey availability may be a more important predictor of predator distribution than habitat suitability. This result supports the need for ecosystem level rather than species-specific conservation measures to support shark recovery. The observed spatial partitioning amongst sites for species and life-stages also implies the need to include a diversity of habitats and reef types within a protected area for adequate protection of reef-associated shark assemblages.
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Affiliation(s)
- David M. Tickler
- Oceans Institute: Centre for Marine Futures, University of Western Australia, 35 Stirling Highway, Crawley, Perth, WA, Australia
- * E-mail:
| | - Tom B. Letessier
- Oceans Institute: Centre for Marine Futures, University of Western Australia, 35 Stirling Highway, Crawley, Perth, WA, Australia
- Zoological Society of London, Regents Park, London, United Kingdom
| | - Heather J. Koldewey
- Zoological Society of London, Regents Park, London, United Kingdom
- Centre for Ecology & Conservation, University of Exeter, Cornwall Campus, United Kingdom
| | - Jessica J. Meeuwig
- Oceans Institute: Centre for Marine Futures, University of Western Australia, 35 Stirling Highway, Crawley, Perth, WA, Australia
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14
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Friess DA, Thompson BS, Brown B, Amir AA, Cameron C, Koldewey HJ, Sasmito SD, Sidik F. Policy challenges and approaches for the conservation of mangrove forests in Southeast Asia. Conserv Biol 2016; 30:933-49. [PMID: 27341487 DOI: 10.1111/cobi.12784] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 08/11/2015] [Accepted: 08/27/2015] [Indexed: 05/06/2023]
Abstract
Many drivers of mangrove forest loss operate over large scales and are most effectively addressed by policy interventions. However, conflicting or unclear policy objectives exist at multiple tiers of government, resulting in contradictory management decisions. To address this, we considered four approaches that are being used increasingly or could be deployed in Southeast Asia to ensure sustainable livelihoods and biodiversity conservation. First, a stronger incorporation of mangroves into marine protected areas (that currently focus largely on reefs and fisheries) could resolve some policy conflicts and ensure that mangroves do not fall through a policy gap. Second, examples of community and government comanagement exist, but achieving comanagement at scale will be important in reconciling stakeholders and addressing conflicting policy objectives. Third, private-sector initiatives could protect mangroves through existing and novel mechanisms in degraded areas and areas under future threat. Finally, payments for ecosystem services (PES) hold great promise for mangrove conservation, with carbon PES schemes (known as blue carbon) attracting attention. Although barriers remain to the implementation of PES, the potential to implement them at multiple scales exists. Closing the gap between mangrove conservation policies and action is crucial to the improved protection and management of this imperiled coastal ecosystem and to the livelihoods that depend on them.
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Affiliation(s)
- Daniel A Friess
- Department of Geography, National University of Singapore, 1 Arts Link, 117570, Singapore.
| | - Benjamin S Thompson
- Department of Geography, National University of Singapore, 1 Arts Link, 117570, Singapore
| | - Ben Brown
- Yayasan Hutan Biru-Blue Forests, Makassar, 90231, Sulawesi, Indonesia
- Research Institute for the Environment and Livelihoods, Charles Darwin University, Ellengowan Drive, Darwin, NT, 0909, Australia
| | - A Aldrie Amir
- Institute for Environment and Development (LESTARI), Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia
| | - Clint Cameron
- Research Institute for the Environment and Livelihoods, Charles Darwin University, Ellengowan Drive, Darwin, NT, 0909, Australia
| | - Heather J Koldewey
- Zoological Society of London, Outer Circle, Regents Park, London, NW1 4RY, U.K
| | - Sigit D Sasmito
- Center for International Forestry Research (CIFOR), Situ Gede, Bogor, 16115, Indonesia
| | - Frida Sidik
- Institute for Marine Research and Observation, Ministry of Fisheries and Marine Affairs, Jalan Baru Perancak, Negara-Jembrana, Bali, 82251, Indonesia
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15
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Duncan C, Primavera JH, Pettorelli N, Thompson JR, Loma RJA, Koldewey HJ. Rehabilitating mangrove ecosystem services: A case study on the relative benefits of abandoned pond reversion from Panay Island, Philippines. Mar Pollut Bull 2016; 109:772-82. [PMID: 27289287 DOI: 10.1016/j.marpolbul.2016.05.049] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 05/13/2016] [Accepted: 05/19/2016] [Indexed: 05/14/2023]
Abstract
Mangroves provide vital climate change mitigation and adaptation (CCMA) ecosystem services (ES), yet have suffered extensive tropics-wide declines. To mitigate losses, rehabilitation is high on the conservation agenda. However, the relative functionality and ES delivery of rehabilitated mangroves in different intertidal locations is rarely assessed. In a case study from Panay Island, Philippines, using field- and satellite-derived methods, we assess carbon stocks and coastal protection potential of rehabilitated low-intertidal seafront and mid- to upper-intertidal abandoned (leased) fishpond areas, against reference natural mangroves. Due to large sizes and appropriate site conditions, targeted abandoned fishpond reversion to former mangrove was found to be favourable for enhancing CCMA in the coastal zone. In a municipality-specific case study, 96.7% of abandoned fishponds with high potential for effective greenbelt rehabilitation had favourable tenure status for reversion. These findings have implications for coastal zone management in Asia in the face of climate change.
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Affiliation(s)
- Clare Duncan
- Institute of Zoology, Zoological Society of London, Outer Circle, Regent's Park, London NW1 4RY, UK; UCL Department of Geography, University College London, Gower Street, London WC1E 6BT, UK.
| | - Jurgenne H Primavera
- Conservation Programmes, Zoological Society of London, Outer Circle, Regent's Park, London NW1 4RY, UK; Zoological Society of London-Philippines, 43-E Burgos Street, Barangay Magdalo, La Paz, 5000 Iloilo City, Philippines
| | - Nathalie Pettorelli
- Institute of Zoology, Zoological Society of London, Outer Circle, Regent's Park, London NW1 4RY, UK
| | - Julian R Thompson
- UCL Department of Geography, University College London, Gower Street, London WC1E 6BT, UK
| | - Rona Joy A Loma
- Conservation Programmes, Zoological Society of London, Outer Circle, Regent's Park, London NW1 4RY, UK; Zoological Society of London-Philippines, 43-E Burgos Street, Barangay Magdalo, La Paz, 5000 Iloilo City, Philippines
| | - Heather J Koldewey
- Conservation Programmes, Zoological Society of London, Outer Circle, Regent's Park, London NW1 4RY, UK; Centre for Ecology and Conservation, University of Exeter, Penryn, Cornwall TR10 9EZ, UK
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16
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Correia M, Caldwell IR, Koldewey HJ, Andrade JP, Palma J. Seahorse (Hippocampinae) population fluctuations in the Ria Formosa Lagoon, south Portugal. J Fish Biol 2015; 87:679-690. [PMID: 26255856 DOI: 10.1111/jfb.12748] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 06/12/2015] [Indexed: 06/04/2023]
Abstract
Comparisons of three sets of surveys in the Ria Formosa Lagoon, Portugal, over a 13 year period (2001-2002, 2008-2009 and 2010-2013) revealed significant population fluctuations in at least one of the two seahorse (Hippocampinae) species living there, and that those fluctuations were potentially associated with habitat changes in the lagoon. After a significant decline between the first two survey periods (2001-2002 v. 2008-2009), long-snouted seahorse Hippocampus guttulatus populations increased significantly between 2008-2009 surveys and new 2010-2013 surveys. There were no significant differences in H. guttulatus populations between the 2001-2002 and 2010-2013 surveys. In contrast, there were no significant differences in short-snouted seahorse Hippocampus hippocampus densities among the 16 sites surveyed throughout the three sampling periods, although the ability to detect any change was hampered by the low densities of this species in all time periods. Fluctuations in H. guttulatus densities were positively correlated with the percentage of holdfast coverage, but with none of the other environmental variables tested. These results highlight the importance of holdfast availability in maintaining stable seahorse populations. While population fluctuations are certainly more promising than a consistent downward decline, such extreme fluctuations observed for seahorses in the Ria Formosa Lagoon could still leave these two species vulnerable to any additional stressors, particularly during low density periods.
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Affiliation(s)
- M Correia
- CCMar, Universidade do Algarve, F. C. T., Edificio 7, Campus de Gambelas, Faro 8005-139, Portugal
| | - I R Caldwell
- Hawaii Institute of Marine Biology, School of Ocean and Earth Science and Technology University of Hawaii at Manoa, P. O. Box 1346, Kaneohe, HI 96744, U.S.A
| | - H J Koldewey
- Project Seahorse, Zoological Society of London, Regent's Park, London NW1 4RY, U.K
| | - J P Andrade
- CCMar, Universidade do Algarve, F. C. T., Edificio 7, Campus de Gambelas, Faro 8005-139, Portugal
| | - J Palma
- CCMar, Universidade do Algarve, F. C. T., Edificio 7, Campus de Gambelas, Faro 8005-139, Portugal
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17
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Letessier TB, Meeuwig JJ, Gollock M, Groves L, Bouchet PJ, Chapuis L, Vianna GM, Kemp K, Koldewey HJ. Assessing pelagic fish populations: The application of demersal video techniques to the mid-water environment. ACTA ACUST UNITED AC 2013. [DOI: 10.1016/j.mio.2013.11.003] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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18
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Hill NAO, Rowcliffe JM, Koldewey HJ, Milner-Gulland EJ. The interaction between seaweed farming as an alternative occupation and fisher numbers in the central Philippines. Conserv Biol 2012; 26:324-34. [PMID: 22098395 DOI: 10.1111/j.1523-1739.2011.01796.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Alternative occupations are frequently promoted as a means to reduce the number of people exploiting declining fisheries. However, there is little evidence that alternative occupations reduce fisher numbers. Seaweed farming is frequently promoted as a lucrative alternative occupation for artisanal fishers in Southeast Asia. We examined how the introduction of seaweed farming has affected village-level changes in the number of fishers on Danajon Bank, central Philippines, where unsustainable fishing has led to declining fishery yields. To determine how fisher numbers had changed since seaweed farming started, we interviewed the heads of household from 300 households in 10 villages to examine their perceptions of how fisher numbers had changed in their village and the reasons they associated with these changes. We then asked key informants (people with detailed knowledge of village members) to estimate fisher numbers in these villages before seaweed farming began and at the time of the survey. We compared the results of how fisher numbers had changed in each village with the wealth, education, seaweed farm sizes, and other attributes of households in these villages, which we collected through interviews, and with village-level factors such as distance to markets. We also asked people why they either continued to engage in or ceased fishing. In four villages, respondents thought seaweed farming and low fish catches had reduced fisher numbers, at least temporarily. In one of these villages, there was a recent return to fishing due to declines in the price of seaweed and increased theft of seaweed. In another four villages, fisher numbers increased as human population increased, despite the widespread uptake of seaweed farming. Seaweed farming failed for technical reasons in two other villages. Our results suggest seaweed farming has reduced fisher numbers in some villages, a result that may be correlated with socioeconomic status, but the heterogeneity of outcomes is consistent with suggestions that alternative occupations are not a substitute for more direct forms of resource management.
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Affiliation(s)
- Nicholas A O Hill
- Centre for Environmental Policy, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom.
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19
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Abstract
This article analyses the pressures on seahorses and explores conservation responses. It focuses on seahorses (Hippocampus spp.) but also considers pipefishes and seadragons, especially where they can fill gaps in seahorse knowledge. The charisma of many syngnathids can make them good flagship species for threats and solutions in marine conservation. The article combines a synthesis of published literature with new data on the trade in seahorses for traditional medicine, aquarium display and curiosities. Most traded seahorses come from trawl by-catch, although seahorses are also targeted. The total extraction is large, tens of millions of animals annually, and unsustainable. A first review of the effect of habitat change on syngnathids raises many questions, while suggesting that some species may cope better than others. The combination of pressures means that many species of syngnathid are now included in the IUCN Red List of Threatened Species or national equivalents. In addition, seahorse exports from 175 countries are limited to sustainable levels under the Convention on International Trade in Endangered Species (CITES) of Wild Fauna and Flora. Possible conservation measures include marine protected areas, fisheries management, select aquaculture ventures, trade regulation, improved governance (particularly) and consumer engagement.
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Affiliation(s)
- A C J Vincent
- Project Seahorse, Fisheries Centre, The University of British Columbia, 2202 Main Mall, Vancouver, V6T 1Z4 Canada.
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20
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Woodall LC, Koldewey HJ, Shaw PW. Historical and contemporary population genetic connectivity of the European short-snouted seahorse Hippocampus hippocampus and implications for management. J Fish Biol 2011; 78:1738-1756. [PMID: 21651525 DOI: 10.1111/j.1095-8649.2011.02974.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
This first genetic study of Hippocampus hippocampus covers the species' entire geographic range and employs two mtDNA markers (control region and cytochrome b) to establish patterns of population structuring. A total of 255 specimens from 21 locations were used to obtain 89 concatenated haplotypes. The common haplotype was present in all but one population, however, most haplotypes were unique. The haplotype network had a star-like construction, suggesting expansion from a bottleneck event. F(ST) and AMOVA revealed population subdivision into three geographic regions (English Channel + Bay of Biscay, Mediterranean Sea + Atlantic Ocean Iberian coast + Macaronesian Islands, and West Africa) with barriers to gene flow indentified at Cape Finisterre and the Cape Verde frontal zone. Neutrality tests and nested clade analysis suggest a complex demographic history, with both historic events and contemporary processes shaping patterns of genetic differentiation. The genetic population subdivision detected in this study indicates that H. hippocampus should be managed as three separate units. This is especially pertinent as H. hippocampus populations within the West African region are the only ones known to be specifically targeted for exploitation.
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Affiliation(s)
- L C Woodall
- School of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK.
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21
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Koldewey HJ, Curnick D, Harding S, Harrison LR, Gollock M. Potential benefits to fisheries and biodiversity of the Chagos Archipelago/British Indian Ocean Territory as a no-take marine reserve. Mar Pollut Bull 2010; 60:1906-1915. [PMID: 20965522 DOI: 10.1016/j.marpolbul.2010.10.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Revised: 10/03/2010] [Accepted: 10/04/2010] [Indexed: 05/30/2023]
Abstract
On 1st April 2010, the British Government announced designation of the British Indian Ocean Territory--or Chagos Archipelago--as the world's largest marine protected area (MPA). This near pristine ocean ecosystem now represents 16% of the worlds fully protected coral reef, 60% of the world's no-take protected areas and an uncontaminated reference site for ecological studies. In addition these gains for biodiversity conservation, the Chagos/BIOT MPA also offers subsidiary opportunities to act as a fisheries management tool for the western Indian Ocean, considering its size and location. While the benefits of MPAs for coral-reef dwelling species are established, there is uncertainty about their effects on pelagic migratory species. This paper reviews the increasing body of evidence to demonstrate that positive, measurable reserve effects exist for pelagic populations and that migratory species can benefit from no-take marine reserves.
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Affiliation(s)
- Heather J Koldewey
- Conservation Programmes, Zoological Society of London, Regents Park, London, UK.
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22
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Abstract
A seahorse specimen from Banco Açores (Azores Archipelago) was identified using morphological and molecular genetic data as Hippocampus erectus. This specimen represents the first record of H. erectus in the eastern Atlantic Ocean, well outside its reported range, and may provide evidence of long-distance translocation in what are assumed to be relatively sedentary fish.
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Affiliation(s)
- L C Woodall
- School of Biological Sciences, Royal Holloway University of London, Egham, Surrey, TW20 0EX, UK.
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23
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Van Look KJW, Dzyuba B, Cliffe A, Koldewey HJ, Holt WV. Dimorphic sperm and the unlikely route to fertilisation in the yellow seahorse. ACTA ACUST UNITED AC 2007; 210:432-7. [PMID: 17234612 DOI: 10.1242/jeb.02673] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Uniquely among vertebrates, seahorses and pipefishes (Family Syngnathidae) incubate their eggs within a male brood pouch. This has contributed to a widespread, but poorly founded belief, that the eggs are fertilised using spermatozoa that are deposited directly into the brood pouch via an internal sperm duct. Anatomical dissections showed, however, not only that direct sperm deposition into the pouch is physically impossible, but that spermatozoa must somehow travel a significant distance (>4 mm) outside the body of the male, to reach and fertilise eggs in the pouch. Observations of courtship and mating behaviour also revealed that the pouch closes immediately after mating, and that sperm transfer must occur within a time window of no more than 6 s. In addition to this, the yellow seahorse produces extraordinarily low quantities of dimorphic spermatozoa, but is nevertheless highly fertile and can produce broods that exceed 100 embryos. The entire fertilisation process in seahorses is therefore uniquely efficient among vertebrates, yet paradoxically involves several steps that would seem to complicate, and even appear to prevent, the interaction of the gametes. Although we are still unable to describe the exact fertilisation mechanism, we speculate that spermatozoa are ejaculated into a mixture of ovarian fluid and eggs, while the male and female are in close contact. Thereafter, this mixture must enter the pouch, whereupon the spermatozoa encounter seawater. These observations also support the view, indirectly inferred in previous publications, that sperm competition in seahorses is not only non-existent but impossible.
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Affiliation(s)
- Katrien J W Van Look
- Institute of Zoology, Zoological Society of London, Regent's Park, London NW1 4RY, UK
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24
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Dzyuba B, Van Look KJW, Cliffe A, Koldewey HJ, Holt WV. Effect of parental age and associated size on fecundity, growth and survival in the yellow seahorse Hippocampus kuda. ACTA ACUST UNITED AC 2006; 209:3055-61. [PMID: 16888054 DOI: 10.1242/jeb.02336] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Seahorses, together with the pipefishes (Family Syngnathidae), are the only vertebrates in which embryonic development takes place within a specialised body compartment, the brood pouch, of the male instead of the female. Embryos develop in close association with the brood pouch epithelium in a manner that bears some resemblance to embryo-placental relationships in mammals. We have explored the hypothesis that parental body size and age should affect offspring postnatal growth and survival if brood pouch quality impacts upon prenatal embryonic nutrition or respiration. Using an aquarium population of the yellow seahorse, Hippocampus kuda, we show here that large parents produce offspring whose initial postnatal growth rates (weeks one to three) were significantly higher than those of the offspring of younger and smaller parents. Whereas 90% of offspring from the larger parents survived for the duration of the study (7 weeks), less that 50% of offspring from smaller parents survived for the same period. For the offspring of large parents, growth rates from individual males were negatively correlated with the number of offspring in the cohort (r=-0.82; P<0.05); this was not the case for offspring from small parents (r=0.048; P>0.9). Observations of embryos within the pouch suggested that when relatively few embryos are present they may attach to functionally advantageous sites and thus gain physiological support during gestation. These results suggest that male body size, and pouch size and function, may influence the future fitness and survival of their offspring.
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Affiliation(s)
- Borys Dzyuba
- Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of the Ukraine, 23 Pereyaslavskaya Street, Kharkov 310015, Ukraine
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