23 results on '"Fordham, Sonja V."'
Search Results
2. Half a century of global decline in oceanic sharks and rays
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Pacoureau, Nathan, Rigby, Cassandra L., Kyne, Peter M., Sherley, Richard B., Winker, Henning, Carlson, John K., and Fordham, Sonja V.
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Biological diversity conservation -- Forecasts and trends ,Stingrays -- Statistics -- Protection and preservation ,Wildlife conservation -- Forecasts and trends ,Rays (Fishes) -- Statistics -- Protection and preservation ,Sharks -- Statistics -- Protection and preservation ,Market trend/market analysis ,Environmental issues ,Science and technology ,Zoology and wildlife conservation - Abstract
Overfishing is the primary cause of marine defaunation, yet declines in and increasing extinction risks of individual species are difficult to measure, particularly for the largest predators found in the high seas.sup.1-3. Here we calculate two well-established indicators to track progress towards Aichi Biodiversity Targets and Sustainable Development Goals.sup.4,5: the Living Planet Index (a measure of changes in abundance aggregated from 57 abundance time-series datasets for 18 oceanic shark and ray species) and the Red List Index (a measure of change in extinction risk calculated for all 31 oceanic species of sharks and rays). We find that, since 1970, the global abundance of oceanic sharks and rays has declined by 71% owing to an 18-fold increase in relative fishing pressure. This depletion has increased the global extinction risk to the point at which three-quarters of the species comprising this functionally important assemblage are threatened with extinction. Strict prohibitions and precautionary science-based catch limits are urgently needed to avert population collapse.sup.6,7, avoid the disruption of ecological functions and promote species recovery.sup.8,9. The global abundance of oceanic sharks and rays has decreased by 71% since 1970 and 24 species are threatened with extinction owing to a concomitant increase in fishing pressure., Author(s): Nathan Pacoureau [sup.1] , Cassandra L. Rigby [sup.2] , Peter M. Kyne [sup.3] , Richard B. Sherley [sup.4] , Henning Winker [sup.5] [sup.6] , John K. Carlson [sup.7] , [...]
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- 2021
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3. Extinction risk and conservation of the world's sharks and rays
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Dulvy, Nicholas K., Fowler, Sarah L., Musick, John A., Cavanagh, Rachel D., Kyne, Peter M., Harrison, Lucy R., Carlson, John K., Davidson, Lindsay N. K., Fordham, Sonja V., Francis, Malcolm P., Pollock, Caroline M., Simpfendorfer, Colin A., Burgess, George H., Carpenter, Kent E., Compagno, Leonard J. V., Ebert, David A., Gibson, Claudine, Heupel, Michelle R., Livingstone, Suzanne R., Sanciangco, Jonnell C., Stevens, John D., Valenti, Sarah, and White, William T.
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Quantitative Biology - Populations and Evolution - Abstract
The rapid expansion of human activities threatens ocean-wide biodiversity loss. Numerous marine animal populations have declined, yet it remains unclear whether these trends are symptomatic of a chronic accumulation of global marine extinction risk. We present the first systematic analysis of threat for a globally-distributed lineage of 1,041 chondrichthyan fishes - sharks, rays, and chimaeras. We estimate that one-quarter are threatened according to IUCN Red List criteria due to overfishing (targeted and incidental). Large-bodied, shallow-water species are at greatest risk and five out of the seven most threatened families are rays. Overall chondrichthyan extinction risk is substantially higher than for most other vertebrates, and only one-third of species are considered safe. Population depletion has occurred throughout the world's ice-free waters, but is particularly prevalent in the Indo-Pacific Biodiversity Triangle and Mediterranean Sea. Improved management of fisheries and trade is urgently needed to avoid extinctions and promote population recovery., Comment: Accepted for publication in eLIFE on 5th December 2013. 83 pages, 9 tables, 10 figures
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- 2013
4. Overfishing drives over one-third of all sharks and rays toward a global extinction crisis
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Dulvy, Nicholas K., primary, Pacoureau, Nathan, additional, Rigby, Cassandra L., additional, Pollom, Riley A., additional, Jabado, Rima W., additional, Ebert, David A., additional, Finucci, Brittany, additional, Pollock, Caroline M., additional, Cheok, Jessica, additional, Derrick, Danielle H., additional, Herman, Katelyn B., additional, Sherman, C. Samantha, additional, VanderWright, Wade J., additional, Lawson, Julia M., additional, Walls, Rachel H.L., additional, Carlson, John K., additional, Charvet, Patricia, additional, Bineesh, Kinattumkara K., additional, Fernando, Daniel, additional, Ralph, Gina M., additional, Matsushiba, Jay H., additional, Hilton-Taylor, Craig, additional, Fordham, Sonja V., additional, and Simpfendorfer, Colin A., additional
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- 2021
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5. Overfishing and Habitat Loss Drives Range Contraction of Iconic Marine Fishes to Near Extinction
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Yan, Helen F., Kyne, Peter M., Jabado, Rima W., Leeney, Ruth H., Davidson, Lindsay N.K., Derrick, Danielle H., Finucci, Brittany, Freckleton, Robert P., Fordham, Sonja V., and Dulvy, Nicholas K.
- Abstract
Extinctions on land are often inferred from sparse sightings over time, but this technique is ill-suited for wide-ranging species. We develop a space-for-time approach to track the spatial contraction and drivers of decline of sawfishes. These iconic and endangered shark-like rays were once found in warm, coastal waters of 90 nations and are now presumed extinct in more than half (n = 46). Using dynamic geography theory, we predict that sawfishes are gone from at least nine additional nations. Overfishing and habitat loss have reduced spatial occupancy, leading to local extinctions in 55 of the 90 nations, which equates to 58.7% of their historical distribution. Retention bans and habitat protections are urgently necessary to secure a future for sawfishes and similar species.
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- 2021
6. Overfishing drives over one-third of all sharks and rays toward a global extinction crisis
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Dulvy, Nicholas K., Pacoureau, Nathan, Rigby, Cassandra L., Pollom, Riley A., Jabado, Rima W., Ebert, David A., Finucci, Brittany, Pollock, Caroline M., Cheok, Jessica, Derrick, Danielle H., Herman, Katelyn B., Sherman, C. Samantha, VanderWright, Wade J., Lawson, Julia M., Walls, Rachel H. L., Carlson, John K., Charvet, Patricia, Bineesh, Kinattumkara K., Fernando, Daniel, Ralph, Gina M., Matsushiba, Jay H., Hilton-Taylor, Craig, Fordham, Sonja, V, Simpfendorfer, Colin A., Dulvy, Nicholas K., Pacoureau, Nathan, Rigby, Cassandra L., Pollom, Riley A., Jabado, Rima W., Ebert, David A., Finucci, Brittany, Pollock, Caroline M., Cheok, Jessica, Derrick, Danielle H., Herman, Katelyn B., Sherman, C. Samantha, VanderWright, Wade J., Lawson, Julia M., Walls, Rachel H. L., Carlson, John K., Charvet, Patricia, Bineesh, Kinattumkara K., Fernando, Daniel, Ralph, Gina M., Matsushiba, Jay H., Hilton-Taylor, Craig, Fordham, Sonja, V, and Simpfendorfer, Colin A.
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The scale and drivers of marine biodiversity loss are being revealed by the International Union for Conservation of Nature (IUCN) Red List assessment process. We present the first global reassessment of 1,199 species in Class Chondrichthyes-sharks, rays, and chimeras. The first global assessment (in 2014) concluded that one-quarter (24%) of species were threatened. Now, 391 (32.6%) species are threatened with extinction. When this percentage of threat is applied to Data Deficient species, more than one-third (37.5%) of chondrichthyans are estimated to be threatened, with much of this change resulting from new information. Three species are Critically Endangered (Possibly Extinct), representing possibly the first globalmarine fish extinctions due to overfishing. Consequently, the chondrichthyan extinction rate is potentially 25 extinctions per million species years, comparable to that of terrestrial vertebrates. Overfishing is the universal threat affecting all 391 threatened species and is the sole threat for 67.3% of species and interacts with three other threats for the remaining third: loss and degradation of habitat (31.2% of threatened species), climate change (10.2%), and pollution (6.9%). Species are disproportionately threatened in tropical and subtropical coastal waters. Science-based limits on fishing, effective marine protected areas, and approaches that reduce or eliminate fishing mortality are urgently needed to minimize mortality of threatened species and ensure sustainable catch and trade of others. Immediate action is essential to prevent further extinctions and protect the potential for food security and ecosystem functions provided by this iconic lineage of predators.
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- 2021
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7. Overfishing and habitat loss drive range contraction of iconic marine fishes to near extinction
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Yan, Helen F., primary, Kyne, Peter M., additional, Jabado, Rima W., additional, Leeney, Ruth H., additional, Davidson, Lindsay N.K., additional, Derrick, Danielle H., additional, Finucci, Brittany, additional, Freckleton, Robert P., additional, Fordham, Sonja V., additional, and Dulvy, Nicholas K., additional
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- 2021
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8. Extinction risk and conservation of critically endangered angel sharks in the Eastern Atlantic and Mediterranean Sea
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Lawson, Julia M, primary, Pollom, Riley A, additional, Gordon, Cat A, additional, Barker, Joanna, additional, Meyers, Eva K M, additional, Zidowitz, Heike, additional, Ellis, Jim R, additional, Bartolí, Álex, additional, Morey, Gabriel, additional, Fowler, Sarah L, additional, Alvarado, David Jiménez, additional, Fordham, Sonja V, additional, Sharp, Rowland, additional, Hood, Ali R, additional, and Dulvy, Nicholas K, additional
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- 2019
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9. Sharks, rays and chimaeras: the status of the chondrichthyan fishes
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Cavanagh, Rachel D., additional, Camhi, Merry, additional, Burgess, George H., additional, Cailliet, Gregor M., additional, Fordham, Sonja V., additional, Simpfendorfer, Colin A., additional, and Musick, John A., additional
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- 2005
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10. Extinction risk and conservation of critically endangered angel sharks in the Eastern Atlantic and Mediterranean Sea.
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Lawson, Julia M, Pollom, Riley A, Gordon, Cat A, Barker, Joanna, Meyers, Eva K M, Zidowitz, Heike, Ellis, Jim R, Bartolí, Álex, Morey, Gabriel, Fowler, Sarah L, Alvarado, David Jiménez, Fordham, Sonja V, Sharp, Rowland, Hood, Ali R, and Dulvy, Nicholas K
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SHARKS ,FISH mortality ,BIOLOGICAL extinction ,CHONDRICHTHYES ,SQUATINIDAE - Abstract
Understanding the details of local and regional extinctions allows for more efficient allocation of conservation activities and resources. This involves identifying where populations persist, where populations may still be present, and where populations may be locally extinct. Three threatened angel sharks occur in the Eastern Atlantic and Mediterranean Sea: Sawback Angelshark (Squatina aculeata), Smoothback Angelshark (Squatina oculata), and Angelshark (Squatina squatina). Population sizes and geographic ranges of these species have been reduced due to overfishing and habitat loss, placing them among the world s most threatened chondrichthyans. We revise distribution maps, review global status, and present a Conservation Strategy to protect and restore these angel shark populations by minimizing fishing mortality, protecting critical habitat, and mitigating human disturbance. Updated distributions reveal that a halving of the geographic extent may have occurred for all three species, with potential declines of 51% for Sawback Angelshark, 48% for Smoothback Angelshark, and 58% for Angelshark. While 20 national and international management measures are now in place for Angelshark, only half of these include the other two species. We encourage further conservation action to adopt and develop this Conservation Strategy to restore angel shark populations to robust levels and safeguard them throughout their range. [ABSTRACT FROM AUTHOR]
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- 2020
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11. Sympathy for the devil : a conservation strategy for devil and manta rays
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Lawson, Julia M., Fordham, Sonja V., O'Malley, Mary P., Davidson, Lindsay N. K., Walls, Rachel H. L., Heupel, Michelle R., Stevens, Guy, Fernando, Daniel, Budziak, Ania, Simpfendorfer, Colin A., Ender, Isabel, Francis, Malcolm P., di Sciara, Giuseppe Notarbartolo, Dulvy, Nicholas K., Lawson, Julia M., Fordham, Sonja V., O'Malley, Mary P., Davidson, Lindsay N. K., Walls, Rachel H. L., Heupel, Michelle R., Stevens, Guy, Fernando, Daniel, Budziak, Ania, Simpfendorfer, Colin A., Ender, Isabel, Francis, Malcolm P., di Sciara, Giuseppe Notarbartolo, and Dulvy, Nicholas K.
- Abstract
Background. International trade for luxury products, medicines, and tonics poses a threat to both terrestrial and marine wildlife. The demand for and consumption of gill plates (known as Peng Yu Sai, "Fish Gill of Mobulid Ray") from devil and manta rays (subfamily Mobulinae, collectively referred to as mobulids) poses a significant threat to these marine fishes because of their extremely low productivity. The demand for these gill plates has driven an international trade supplied by largely unmonitored and unregulated catches from target, and incidental fisheries around the world. Scientific research, conservation campaigns, and legal protections for devil rays have lagged behind those for manta rays despite similar threats across all mobufids. Methods. To investigate the difference in attention given to devil rays and manta rays, we examined trends in the scientific literature and updated species distribution maps for all mobufids. Using available information on target and incidental fisheries, and gathering information on fishing and trade regulations (at international, national, and territorial levels), we examined how threats and protective measures overlap with species distribution. We then used a species conservation planning approach to develop the Global Devil and Manta Ray Conservation Strategy, specifying a vision, goals, objectives, and actions to advance the knowledge and protection of both devil and manta rays. Results and Discussion. Our literature review revealed that there had been nearly 2.5-times more "manta"-titled publications, than "mobula" or "devil ray"-titled publications over the Past 4.5 years (January 2012 June 2016). The majority of these recent publications were reports on occurrence of mobulid species. These publications contributed to updated Area of Occupancy and Extent of Occurrence maps which showed expanded distributions for most mobulid species and overlap between the two genera. While several international protections have recent
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- 2017
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12. Challenges and Priorities in Shark and Ray Conservation
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Dulvy, Nicholas K., primary, Simpfendorfer, Colin A., additional, Davidson, Lindsay N.K., additional, Fordham, Sonja V., additional, Bräutigam, Amie, additional, Sant, Glenn, additional, and Welch, David J., additional
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- 2017
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13. Sympathy for the devil: a conservation strategy for devil and manta rays
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Lawson, Julia M., primary, Fordham, Sonja V., additional, O’Malley, Mary P., additional, Davidson, Lindsay N.K., additional, Walls, Rachel H.L., additional, Heupel, Michelle R., additional, Stevens, Guy, additional, Fernando, Daniel, additional, Budziak, Ania, additional, Simpfendorfer, Colin A., additional, Ender, Isabel, additional, Francis, Malcolm P., additional, Notarbartolo di Sciara, Giuseppe, additional, and Dulvy, Nicholas K., additional
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- 2017
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14. Sympathy for the devil: a conservation strategy for devil and manta rays
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Lawson, Julia M, primary, Walls, Rachel HL, additional, Fordham, Sonja V, additional, O'Malley, Mary P, additional, Heupel, Michelle R, additional, Stevens, Guy, additional, Fernando, Daniel, additional, Budziak, Ania, additional, Simpfendorfer, Colin A, additional, Davidson, Lindsay NK, additional, Ender, Isabel, additional, Francis, Malcolm P, additional, Notarbartolo di Sciara, Giuseppe, additional, and Dulvy, Nicholas K, additional
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- 2016
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15. Extinction risk and conservation of the world's sharks and rays
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Dulvy, Nicholas K., Fowler, Sarah L., Musick, John A., Cavanagh, Rachel D., Kyne, Peter M., Harrison, Lucy R., Carlson, John K., Davidson, Lindsay N.K., Fordham, Sonja V., Francis, Malcolm P., Pollock, Caroline M., Simpfendorfer, Colin A., Burgess, George H., Carpenter, Kent E., Compagno, Leonard J.V., Ebert, David A., Gibson, Claudine, Heupel, Michelle R., Livingstone, Suzanne R., Sanciangco, Jonnell C., Stevens, John D., Valenti, Sarah, White, William T., Dulvy, Nicholas K., Fowler, Sarah L., Musick, John A., Cavanagh, Rachel D., Kyne, Peter M., Harrison, Lucy R., Carlson, John K., Davidson, Lindsay N.K., Fordham, Sonja V., Francis, Malcolm P., Pollock, Caroline M., Simpfendorfer, Colin A., Burgess, George H., Carpenter, Kent E., Compagno, Leonard J.V., Ebert, David A., Gibson, Claudine, Heupel, Michelle R., Livingstone, Suzanne R., Sanciangco, Jonnell C., Stevens, John D., Valenti, Sarah, and White, William T.
- Abstract
The rapid expansion of human activities threatens ocean-wide biodiversity. Numerous marine animal populations have declined, yet it remains unclear whether these trends are symptomatic of a chronic accumulation of global marine extinction risk. We present the first systematic analysis of threat for a globally distributed lineage of 1,041 chondrichthyan fishes—sharks, rays, and chimaeras. We estimate that one-quarter are threatened according to IUCN Red List criteria due to overfishing (targeted and incidental). Large-bodied, shallow-water species are at greatest risk and five out of the seven most threatened families are rays. Overall chondrichthyan extinction risk is substantially higher than for most other vertebrates, and only one-third of species are considered safe. Population depletion has occurred throughout the world’s ice-free waters, but is particularly prevalent in the Indo-Pacific Biodiversity Triangle and Mediterranean Sea. Improved management of fisheries and trade is urgently needed to avoid extinctions and promote population recovery.
- Published
- 2014
16. Domestic and International Management for Pelagic Sharks
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Camhi, Merry D., primary, Fordham, Sonja V., additional, and Fowler, Sarah L., additional
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17. Ghosts of the coast: global extinction risk and conservation of sawfishes
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Dulvy, Nicholas K., primary, Davidson, Lindsay N. K., additional, Kyne, Peter M., additional, Simpfendorfer, Colin A., additional, Harrison, Lucy R., additional, Carlson, John K., additional, and Fordham, Sonja V., additional
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- 2014
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18. The Last Frontier: Catch Records of White Sharks (Carcharodon carcharias) in the Northwest Pacific Ocean
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Christiansen, Heather M., primary, Lin, Victor, additional, Tanaka, Sho, additional, Velikanov, Anatoly, additional, Mollet, Henry F., additional, Wintner, Sabine P., additional, Fordham, Sonja V., additional, Fisk, Aaron T., additional, and Hussey, Nigel E., additional
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- 2014
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19. Extinction risk and conservation of the world’s sharks and rays
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Dulvy, Nicholas K, primary, Fowler, Sarah L, additional, Musick, John A, additional, Cavanagh, Rachel D, additional, Kyne, Peter M, additional, Harrison, Lucy R, additional, Carlson, John K, additional, Davidson, Lindsay NK, additional, Fordham, Sonja V, additional, Francis, Malcolm P, additional, Pollock, Caroline M, additional, Simpfendorfer, Colin A, additional, Burgess, George H, additional, Carpenter, Kent E, additional, Compagno, Leonard JV, additional, Ebert, David A, additional, Gibson, Claudine, additional, Heupel, Michelle R, additional, Livingstone, Suzanne R, additional, Sanciangco, Jonnell C, additional, Stevens, John D, additional, Valenti, Sarah, additional, and White, William T, additional
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- 2014
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20. Author response: Extinction risk and conservation of the world’s sharks and rays
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Dulvy, Nicholas K, primary, Fowler, Sarah L, additional, Musick, John A, additional, Cavanagh, Rachel D, additional, Kyne, Peter M, additional, Harrison, Lucy R, additional, Carlson, John K, additional, Davidson, Lindsay NK, additional, Fordham, Sonja V, additional, Francis, Malcolm P, additional, Pollock, Caroline M, additional, Simpfendorfer, Colin A, additional, Burgess, George H, additional, Carpenter, Kent E, additional, Compagno, Leonard JV, additional, Ebert, David A, additional, Gibson, Claudine, additional, Heupel, Michelle R, additional, Livingstone, Suzanne R, additional, Sanciangco, Jonnell C, additional, Stevens, John D, additional, Valenti, Sarah, additional, and White, William T, additional
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- 2013
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21. Ghosts of the coast: global extinction risk and conservation of sawfishes.
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Dulvy, Nicholas K., Davidson, Lindsay N. K., Kyne, Peter M., Simpfendorfer, Colin A., Harrison, Lucy R., Carlson, John K., and Fordham, Sonja V.
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SAWFISHES ,BIOLOGICAL extinction ,FISH conservation ,MARINE fishes ,RARE fishes - Abstract
Sawfish are arguably the world's most imperilled marine fishes. All five species are classified as highly threatened with extinction: three are Critically Endangered (smalltooth sawfish Pristis pectinata, largetooth sawfish Pristis pristis, and green sawfish Pristis zijsron); two are Endangered (narrow sawfish Anoxypristis cuspidata, and dwarf sawfish Pristis clavata)., Sawfishes are threatened primarily due to a combination of their low intrinsic rates of population increase, high catchability in fisheries, and high value. Sawfishes are among the world's largest marine fishes, and they are caught by a wide range of fishing gears owing to their tooth-studded rostra being easily entangled. Sawfish fins are some of the most valuable for shark fin soup, and their rostra have long been traded as curios. In addition, they inhabit shallow coastal waters, estuaries, and rivers of the tropics and subtropics, down to a maximum depth rarely exceeding 100 m and are associated with threatened mangrove and seagrass habitats., Historically, sawfishes were distributed in the coastal waters of 90 countries and territories. Over the past century, their geographic distribution has been greatly diminished. For example, the smalltooth sawfish is now found in <20% of its former range. Globally, sawfishes are now entirely absent from 20 countries; 43 countries have lost at least one species., Sawfishes are legally protected, to some degree, in 16 of the 90 range states. These safeguards encompass, on average, 81% of their Extant distribution; however, the quality and breadth of protection varies dramatically across countries and species. Smalltooth sawfish currently has the least amount of such coverage of only half (49%) of Extant distribution., The global conservation strategy specifies actions to protect sawfish and their habitats. Such actions are urgently warranted to avoid global extinction and to restore robust populations for the benefit of coastal ecosystem function and biodiversity., © 2014 The Authors. Aquatic Conservation: Marine and Freshwater Ecosystems published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]
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- 2016
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22. The Last Frontier: Catch Records of White Sharks (Carcharodon carcharias) in the Northwest Pacific Ocean.
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Christiansen, Heather M., Lin, Victor, Tanaka, Sho, Velikanov, Anatoly, Mollet, Henry F., Wintner, Sabine P., Fordham, Sonja V., Fisk, Aaron T., and Hussey, Nigel E.
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WHITE shark ,MARINE animals ,MARINE biology ,FISHERIES ,META-analysis - Abstract
White sharks are highly migratory apex predators, globally distributed in temperate, sub-tropical, and tropical waters. Knowledge of white shark biology and ecology has increased recently based on research at known aggregation sites in the Indian, Atlantic, and Northeast Pacific Oceans; however, few data are available for the Northwest Pacific Ocean. This study provides a meta-analysis of 240 observations of white sharks from the Northwest Pacific Ocean between 1951 and 2012. Records comprise reports of bycatch in commercial fisheries, media accounts, personal communications, and documentation of shark-human interactions from Russia (n = 8), Republic of Korea (22), Japan (129), China (32), Taiwan (45), Philippines (1) and Vietnam (3). Observations occurred in all months, excluding October-January in the north (Russia and Republic of Korea) and July-August in the south (China, Taiwan, Philippines, and Vietnam). Population trend analysis indicated that the relative abundance of white sharks in the region has remained relatively stable, but parameterization of a 75% increase in observer effort found evidence of a minor decline since 2002. Reliably measured sharks ranged from 126–602 cm total length (TL) and 16–2530 kg total weight. The largest shark in this study (602 cm TL) represents the largest measured shark on record worldwide. For all countries combined the sex ratio was non-significantly biased towards females (1∶1.1; n = 113). Of 60 females examined, 11 were confirmed pregnant ranging from the beginning stages of pregnancy (egg cases) to near term (140 cm TL embryos). On average, 6.0±2.2 embryos were found per litter (maximum of 10) and gestation period was estimated to be 20 months. These observations confirm that white sharks are present in the Northwest Pacific Ocean year-round. While acknowledging the difficulties of studying little known populations of a naturally low abundance species, these results highlight the need for dedicated research to inform regional conservation and management planning. [ABSTRACT FROM AUTHOR]
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- 2014
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23. Linking sensory biology and fisheries bycatch reduction in elasmobranch fishes: a review with new directions for research.
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Jordan, Laura K., Mandelman, John W., McComb, D. Michelle, Fordham, Sonja V., Carlson, John K., and Werner, Timothy B.
- Published
- 2013
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