The Sharks of North America
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Chapter 11 the Biology and Ecology of the Oceanic Whitetip Shark, Carcharhinus Longimanus
Chapter 11 The Biology and Ecology of the Oceanic Whitetip Shark, Carcharhinus longimanus Ramón Bonfi l, Shelley Clarke and Hideki Nakano Abstract The oceanic whitetip shark (Carcharhinus longimanus) is a common circumtropical preda- tor and is taken as bycatch in many oceanic fi sheries. This summary of its life history, dis- tribution and abundance, and fi shery-related information is supplemented with unpublished data taken during Japanese tuna research operations in the Pacifi c Ocean. Oceanic whitetips are moderately slow-growing sharks that do not appear to have differential growth rates by sex, and individuals in the Atlantic and Pacifi c Oceans seem to grow at similar rates. They reach sexual maturity at approximately 170–200 cm total length (TL), or 4–7 years of age, and have a 9- to 12-month embryonic development period. Pupping and nursery areas are thought to exist in the central Pacifi c, between 0ºN and 15ºN. According to two demographic metrics, the resilience of C. longimanus to fi shery exploitation is similar to that of blue and shortfi n mako sharks. Nevertheless, reported oceanic whitetip shark catches in several major longline fi sheries represent only a small fraction of total shark catches, and studies in the Northwest Atlantic and Gulf of Mexico suggest that this species has suffered signifi cant declines in abundance. Stock assessment has been severely hampered by the lack of species-specifi c catch data in most fi sheries, but recent implementation of species-based reporting by the International Commission for the Conservation of Atlantic Tunas (ICCAT) and some of its member countries will provide better data for quantitative assessment. -
Sharks for the Aquarium and Considerations for Their Selection1 Alexis L
FA179 Sharks for the Aquarium and Considerations for Their Selection1 Alexis L. Morris, Elisa J. Livengood, and Frank A. Chapman2 Introduction The Lore of the Shark Sharks are magnificent animals and an exciting group Though it has been some 35 years since the shark in Steven of fishes. As a group, sharks, rays, and skates belong to Spielberg’s Jaws bit into its first unsuspecting ocean swim- the biological taxonomic class called Chondrichthyes, or mer and despite the fact that the risk of shark-bite is very cartilaginous fishes (elasmobranchs). The entire supporting small, fear of sharks still makes some people afraid to swim structure of these fish is composed primarily of cartilage in the ocean. (The chance of being struck by lightning is rather than bone. There are some 400 described species of greater than the chance of shark attack.) The most en- sharks, which come in all different sizes from the 40-foot- grained shark image that comes to a person’s mind is a giant long whale shark (Rhincodon typus) to the 2-foot-long conical snout lined with multiple rows of teeth efficient at marble catshark (Atelomycterus macleayi). tearing, chomping, or crushing prey, and those lifeless and staring eyes. The very adaptations that make sharks such Although sharks have been kept in public aquariums successful predators also make some people unnecessarily since the 1860s, advances in marine aquarium systems frightened of them. This is unfortunate, since sharks are technology and increased understanding of shark biology interesting creatures and much more than ill-perceived and husbandry now allow hobbyists to maintain and enjoy mindless eating machines. -
Sharks in Crisis: a Call to Action for the Mediterranean
REPORT 2019 SHARKS IN CRISIS: A CALL TO ACTION FOR THE MEDITERRANEAN WWF Sharks in the Mediterranean 2019 | 1 fp SECTION 1 ACKNOWLEDGEMENTS Written and edited by WWF Mediterranean Marine Initiative / Evan Jeffries (www.swim2birds.co.uk), based on data contained in: Bartolí, A., Polti, S., Niedermüller, S.K. & García, R. 2018. Sharks in the Mediterranean: A review of the literature on the current state of scientific knowledge, conservation measures and management policies and instruments. Design by Catherine Perry (www.swim2birds.co.uk) Front cover photo: Blue shark (Prionace glauca) © Joost van Uffelen / WWF References and sources are available online at www.wwfmmi.org Published in July 2019 by WWF – World Wide Fund For Nature Any reproduction in full or in part must mention the title and credit the WWF Mediterranean Marine Initiative as the copyright owner. © Text 2019 WWF. All rights reserved. Our thanks go to the following people for their invaluable comments and contributions to this report: Fabrizio Serena, Monica Barone, Adi Barash (M.E.C.O.), Ioannis Giovos (iSea), Pamela Mason (SharkLab Malta), Ali Hood (Sharktrust), Matthieu Lapinksi (AILERONS association), Sandrine Polti, Alex Bartoli, Raul Garcia, Alessandro Buzzi, Giulia Prato, Jose Luis Garcia Varas, Ayse Oruc, Danijel Kanski, Antigoni Foutsi, Théa Jacob, Sofiane Mahjoub, Sarah Fagnani, Heike Zidowitz, Philipp Kanstinger, Andy Cornish and Marco Costantini. Special acknowledgements go to WWF-Spain for funding this report. KEY CONTACTS Giuseppe Di Carlo Director WWF Mediterranean Marine Initiative Email: [email protected] Simone Niedermueller Mediterranean Shark expert Email: [email protected] Stefania Campogianni Communications manager WWF Mediterranean Marine Initiative Email: [email protected] WWF is one of the world’s largest and most respected independent conservation organizations, with more than 5 million supporters and a global network active in over 100 countries. -
Western Spotted Catshark, Asymbolus Occiduus
Published Date: 1 March 2019 Western Spotted Catshark, Asymbolus occiduus Report Card Sustainable assessment IUCN Red List IUCN Red List Australian Endemic to Australia Global Least Concern Assessment Assessment Assessors Simpfendorfer, C. & Heupel, M.R. Report Card Remarks Little known shark with limited fishing across its range Summary The Western Spotted Catshark is a small, little known temperate catshark. It is endemic to southern Australia and has a reasonably large geographic and depth range. The species is unlikely to Source: CSIRO National Fish Collection. License: CC BY Attribution be negatively affected by commercial fisheries because there is limited fishing throughout its range. Therefore, it is assessed as Least Concern (IUCN) and Sustainable (SAFS). Distribution The Western Spotted Catshark is distributed along the southern and western coasts of Australia from Fowlers Bay (South Australia) to Perth (Western Australia) (Last and Stevens 2009). Stock structure and status There is currently no information on population size, structure, or trend for the species. Fisheries The Western Spotted Catshark is caught incidentally and very infrequently in the Southern and Eastern Scalefish and Shark Fishery (SESSF). An estimated 69 kg of the species were caught and discarded annually from 2000 to 2006 (Walker and Gason 2007). Habitat and biology The Western Spotted Catshark is found at depths of 98 to 400 m and is most abundant on the outer continental shelf and common off the Western Australian coast. The biology of the species is almost entirely unknown. Adults and juveniles differ significantly in their colour patterns and the association between the two forms was only made recently (Last and Stevens 2009). -
Can Threshold Foraging Responses of Basking Sharks Be Used to Estimate Their Metabolic Rate?
MARINE ECOLOGY PROGRESS SERIES Vol. 200: 289-296,2000 Published July 14 Mar Ecol Prog Ser ~ NOTE Can threshold foraging responses of basking sharks be used to estimate their metabolic rate? David W. Sims* Department of Zoology, University of Aberdeen. Tillydrone Avenue. Aberdeen AB24 2TZ. United Kingdom ABSTRACT: Empirical and theoretical determinations of There are 3 species of filter-feeding shark, the whale minimum threshold prey densities for filter-feeding basking shark ~hi~~~d~~typus of warm-temperate and tropical sharks Cetorhinus maximus were used to test the idea that threshold foraging behaviour could provide a means for esti- seas worldwide, the basking shark Cetorhinus max- mating oxygen consumption (a proxy for metabolic rate). The im~~that inhabits warm-temperate to boreal waters threshold feeding levelrepres&nts the prey density at which circumglobally, and the megamouth shark Mega- there will be no net energy gain (energy intake equals expen- chasms pelagjos occurs in the Pacific and At- diture). Basking sharks were observed to cease feeding at lantic, primarily in deep water (Compagno 1984, Yano their theoretical threshold; thus, the assumption underpin- ning the concept presented here was that over the narrow et They are the largest marine verte- range of zooplankton prey densities that induce 'switching' brates attaining body lengths of up to 14, 10 and 6 m re- between feeding and non-feeding in basking sharks, the spectively. Comparatively little is known about the bi- energetic value of the minimum threshold prey density is ology of planktivorous sharks despite the fact that they equivalent to the shark's instantaneous level of energy expen- diture. -
An Introduction to the Classification of Elasmobranchs
An introduction to the classification of elasmobranchs 17 Rekha J. Nair and P.U Zacharia Central Marine Fisheries Research Institute, Kochi-682 018 Introduction eyed, stomachless, deep-sea creatures that possess an upper jaw which is fused to its cranium (unlike in sharks). The term Elasmobranchs or chondrichthyans refers to the The great majority of the commercially important species of group of marine organisms with a skeleton made of cartilage. chondrichthyans are elasmobranchs. The latter are named They include sharks, skates, rays and chimaeras. These for their plated gills which communicate to the exterior by organisms are characterised by and differ from their sister 5–7 openings. In total, there are about 869+ extant species group of bony fishes in the characteristics like cartilaginous of elasmobranchs, with about 400+ of those being sharks skeleton, absence of swim bladders and presence of five and the rest skates and rays. Taxonomy is also perhaps to seven pairs of naked gill slits that are not covered by an infamously known for its constant, yet essential, revisions operculum. The chondrichthyans which are placed in Class of the relationships and identity of different organisms. Elasmobranchii are grouped into two main subdivisions Classification of elasmobranchs certainly does not evade this Holocephalii (Chimaeras or ratfishes and elephant fishes) process, and species are sometimes lumped in with other with three families and approximately 37 species inhabiting species, or renamed, or assigned to different families and deep cool waters; and the Elasmobranchii, which is a large, other taxonomic groupings. It is certain, however, that such diverse group (sharks, skates and rays) with representatives revisions will clarify our view of the taxonomy and phylogeny in all types of environments, from fresh waters to the bottom (evolutionary relationships) of elasmobranchs, leading to a of marine trenches and from polar regions to warm tropical better understanding of how these creatures evolved. -
NPOA Sharks Booklet.Indd
National Plan of Action for the Conservation and Management of Sharks (NPOA-Sharks) November 2013 South Africa Department of Agriculture, Forestry and Fisheries Private Bag X2, Rogge Bay, 8012 Tel: 021 402 3911 Fax: +27 21 402 3364 www.daff.gov.za Design and Layout: FNP Communications and Gerald van Tonder Photographs courtesy of: Department of Agriculture, Forestry and Fisheries (DAFF), Craig Smith, Charlene da Silva, Rob Tarr Foreword South Africa’s Exclusive Economic Zone is endowed with a rich variety of marine living South Africa is signatory to the Code of Conduct for Responsible Fisheries – voluntarily agreed to by members of the United Nations Food and Agriculture Organisation (FAO) – and, as such, is committed to the development and implementation of National Plans of Action (NPOAs) as adopted by the twenty-third session of the FAO Committee on Fisheries in February 1999 and endorsed by the FAO Council in June 1999. Seabirds – aimed at reducing incidental catch and promoting the conservation of seabirds Fisheries and now regularly conducts Ecological Risk Assessments for all the commercial practices. Acknowledging the importance of maintaining a healthy marine ecosystem and the possibility of major detrimental effects due to the disappearance of large predators, South from the list of harvestable species. In accordance with international recommendations, South Africa subsequently banned the landing of a number of susceptible shark species, including oceanic whitetip, silky, thresher and hammerhead sharks. improves monitoring efforts for foreign vessels discharging shark products in its ports. To ensure long-term sustainability of valuable, but biologically limited, shark resources The NPOA-Sharks presented here formalises and streamlines ongoing efforts to improve conservation and management of sharks caught in South African waters. -
Morphological and Mitochondrial DNA Divergence Validates Blackmouth, Galeus Melastomus, and Atlantic Sawtail Catsharks, Galeus Atlanticus,Asseparatespecies
Journal of Fish Biology (2007) 70 (Supplement C), 346–358 doi:10.1111/j.1095-8649.2007.01455.x, available online at http://www.blackwell-synergy.com Morphological and mitochondrial DNA divergence validates blackmouth, Galeus melastomus, and Atlantic sawtail catsharks, Galeus atlanticus,asseparatespecies R. CASTILHO*†, M. FREITAS*, G. SILVA*, J. FERNANDEZ-CARVALHO‡ AND R. COELHO‡ *Biodiversity and Conservation Group, CCMAR, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal and ‡Coastal Fisheries Research Group, CCMAR, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal (Received 30 August 2006, Accepted 17 January 2007) A total of 60 morphometric traits and nucleotide sequences of the entire mtDNA NADH dehydrogenase subunit 2 (ND2) gene [1047 base pair (bp)] in 23 individuals of blackmouth, Galeus melastomus, and 13 individuals of sawtail catsharks, Galeus atlanticus, caught in Southern Portugal, were examined to test the validity of these two taxa. These sharks closely resemble each other, have overlapping geographical ranges and are difficult to identify by morphological characters. Non-metric multidimensional scaling of morphometric variables indicates a clear separation between the two species, with 10 characters each contributing 2Á12–2Á45% of the total variability between species. Maximum likelihood, parsimony and neighbour-joining trees revealed two major mtDNA haplotype clades, corresponding to the two species, with an average corrected sequence divergence between them of 3Á39 Æ 0Á56%. Within species divergences between haplotypes averaged 0Á27 Æ 0Á18% in G. melastomus and 0Á12 Æ 0Á08% in G. atlanticus. A total of 35 diagnostic nucleotide site differences and four restriction fragment length polymorphism recognition sites in the ND2 gene can be used to distinguish the two species. -
Reproductive Biology of the Bonnethead (Sphyrna Tiburo) from the Southeastern U.S
University of North Florida UNF Digital Commons UNF Graduate Theses and Dissertations Student Scholarship 2014 Reproductive Biology of the Bonnethead (Sphyrna tiburo) from the Southeastern U.S. Atlantic Coast Melissa I. Gonzalez De Acevedo University of North Florida, [email protected] Follow this and additional works at: https://digitalcommons.unf.edu/etd Part of the Biology Commons, and the Ecology and Evolutionary Biology Commons Suggested Citation Gonzalez De Acevedo, Melissa I., "Reproductive Biology of the Bonnethead (Sphyrna tiburo) from the Southeastern U.S. Atlantic Coast" (2014). UNF Graduate Theses and Dissertations. 534. https://digitalcommons.unf.edu/etd/534 This Master's Thesis is brought to you for free and open access by the Student Scholarship at UNF Digital Commons. It has been accepted for inclusion in UNF Graduate Theses and Dissertations by an authorized administrator of UNF Digital Commons. For more information, please contact Digital Projects. © 2014 All Rights Reserved REPRODUCTIVE BIOLOGY OF THE BONNETHEAD (SPHYRNA TIBURO) FROM THE SOUTHEASTERN U.S. ATLANTIC COAST by Melissa Gonzalez De Acevedo A thesis submitted to the Department of Biology in partial fulfillment of the requirements for the degree of Masters of Science in Biology UNIVERSITY OF NORTH FLORIDA COLLEGE OF ARTS AND SCIENCES December 2014 Unpublished work, © Melissa Gonzalez De Acevedo CERTIFICATE OF APPROVAL The thesis “Reproductive biology of the bonnethead (Sphyrna tiburo) from the southeastern U.S. Atlantic coast” submitted by Melissa Gonzalez De Acevedo Approved by the thesis committee: Date Dr. Jim Gelsleichter Committee Chair Dr. Carolyn Belcher Dr. Eric Johnson Accepted for the Department of Biology: Dr. Cliff Ross Assistant Chair Accepted for the College of Arts and Sciences: Dr. -
© Iccat, 2007
A5 By-catch Species APPENDIX 5: BY-CATCH SPECIES A.5 By-catch species By-catch is the unintentional/incidental capture of non-target species during fishing operations. Different types of fisheries have different types and levels of by-catch, depending on the gear used, the time, area and depth fished, etc. Article IV of the Convention states: "the Commission shall be responsible for the study of the population of tuna and tuna-like fishes (the Scombriformes with the exception of Trichiuridae and Gempylidae and the genus Scomber) and such other species of fishes exploited in tuna fishing in the Convention area as are not under investigation by another international fishery organization". The following is a list of by-catch species recorded as being ever caught by any major tuna fishery in the Atlantic/Mediterranean. Note that the lists are qualitative and are not indicative of quantity or mortality. Thus, the presence of a species in the lists does not imply that it is caught in significant quantities, or that individuals that are caught necessarily die. Skates and rays Scientific names Common name Code LL GILL PS BB HARP TRAP OTHER Dasyatis centroura Roughtail stingray RDC X Dasyatis violacea Pelagic stingray PLS X X X X Manta birostris Manta ray RMB X X X Mobula hypostoma RMH X Mobula lucasana X Mobula mobular Devil ray RMM X X X X X Myliobatis aquila Common eagle ray MYL X X Pteuromylaeus bovinus Bull ray MPO X X Raja fullonica Shagreen ray RJF X Raja straeleni Spotted skate RFL X Rhinoptera spp Cownose ray X Torpedo nobiliana Torpedo -
Electrosensory Pore Distribution and Feeding in the Basking Shark Cetorhinus Maximus (Lamniformes: Cetorhinidae)
Vol. 12: 33–36, 2011 AQUATIC BIOLOGY Published online March 3 doi: 10.3354/ab00328 Aquat Biol NOTE Electrosensory pore distribution and feeding in the basking shark Cetorhinus maximus (Lamniformes: Cetorhinidae) Ryan M. Kempster*, Shaun P. Collin The UWA Oceans Institute and the School of Animal Biology, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia ABSTRACT: The basking shark Cetorhinus maximus is the second largest fish in the world, attaining lengths of up to 10 m. Very little is known of its sensory biology, particularly in relation to its feeding behaviour. We describe the abundance and distribution of ampullary pores over the head and pro- pose that both the spacing and orientation of electrosensory pores enables C. maximus to use passive electroreception to track the diel vertical migrations of zooplankton that enable the shark to meet the energetic costs of ram filter feeding. KEY WORDS: Ampullae of Lorenzini · Electroreception · Filter feeding · Basking shark Resale or republication not permitted without written consent of the publisher INTRODUCTION shark Rhincodon typus and the megamouth shark Megachasma pelagios, which can attain lengths of up Electroreception is an ancient sensory modality that to 14 and 6 m, respectively (Compagno 1984). These 3 has evolved independently across the animal kingdom filter-feeding sharks are among the largest living in multiple groups (Scheich et al. 1986, Collin & White- marine vertebrates (Compagno 1984) and yet they are head 2004). Repeated independent evolution of elec- all able to meet their energetic costs through the con- troreception emphasises the importance of this sense sumption of tiny zooplankton. -
Florida's Fintastic Sharks and Rays Lesson and Activity Packet
Florida's Fintastic Sharks and Rays An at-home lesson for grades 3-5 Produced by: This educational workbook was produced through the support of the Indian River Lagoon National Estuary Program. 1 What are sharks and rays? Believe it or not, they’re a type of fish! When you think “fish,” you probably picture a trout or tuna, but fishes come in all shapes and sizes. All fishes share the following key characteristics that classify them into this group: Fishes have the simplest of vertebrate hearts with only two chambers- one atrium and one ventricle. The spine in a fish runs down the middle of its back just like ours, making fish vertebrates. All fishes have skeletons, but not all fish skeletons are made out of bones. Some fishes have skeletons made out of cartilage, just like your nose and ears. Fishes are cold-blooded. Cold-blooded animals use their environment to warm up or cool down. Fins help fish swim. Fins come in pairs, like pectoral and pelvic fins or are singular, like caudal or anal fins. Later in this packet, we will look at the different types of fins that fishes have and some of the unique ways they are used. 2 Placoid Ctenoid Ganoid Cycloid Hard protective scales cover the skin of many fish species. Scales can act as “fingerprints” to help identify some fish species. There are several different scale types found in bony fishes, including cycloid (round), ganoid (rectangular or diamond), and ctenoid (scalloped). Cartilaginous fishes have dermal denticles (Placoid) that resemble tiny teeth on their skin.