Enhanced Visual Fields in Hammerhead Sharks
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Malaysia National Plan of Action for the Conservation and Management of Shark (Plan2)
MALAYSIA NATIONAL PLAN OF ACTION FOR THE CONSERVATION AND MANAGEMENT OF SHARK (PLAN2) DEPARTMENT OF FISHERIES MINISTRY OF AGRICULTURE AND AGRO-BASED INDUSTRY MALAYSIA 2014 First Printing, 2014 Copyright Department of Fisheries Malaysia, 2014 All Rights Reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic, mechanical, including photocopy, recording, or any information storage and retrieval system, without prior permission in writing from the Department of Fisheries Malaysia. Published in Malaysia by Department of Fisheries Malaysia Ministry of Agriculture and Agro-based Industry Malaysia, Level 1-6, Wisma Tani Lot 4G2, Precinct 4, 62628 Putrajaya Malaysia Telephone No. : 603 88704000 Fax No. : 603 88891233 E-mail : [email protected] Website : http://dof.gov.my Perpustakaan Negara Malaysia Cataloguing-in-Publication Data ISBN 978-983-9819-99-1 This publication should be cited as follows: Department of Fisheries Malaysia, 2014. Malaysia National Plan of Action for the Conservation and Management of Shark (Plan 2), Ministry of Agriculture and Agro- based Industry Malaysia, Putrajaya, Malaysia. 50pp SUMMARY Malaysia has been very supportive of the International Plan of Action for Sharks (IPOA-SHARKS) developed by FAO that is to be implemented voluntarily by countries concerned. This led to the development of Malaysia’s own National Plan of Action for the Conservation and Management of Shark or NPOA-Shark (Plan 1) in 2006. The successful development of Malaysia’s second National Plan of Action for the Conservation and Management of Shark (Plan 2) is a manifestation of her renewed commitment to the continuous improvement of shark conservation and management measures in Malaysia. -
The Bonnethead (Sphyrna Tiburo) and the Scalloped Hammerhead (Sphyrna Lewini) Sarah L
© 2017. Published by The Company of Biologists Ltd | Journal of Experimental Biology (2017) 220, 3336-3343 doi:10.1242/jeb.157941 RESEARCH ARTICLE Regional variation in undulatory kinematics of two hammerhead species: the bonnethead (Sphyrna tiburo) and the scalloped hammerhead (Sphyrna lewini) Sarah L. Hoffmann1,*, Steven M. Warren2 and Marianne E. Porter1 ABSTRACT blochii), possesses a cephalofoil that is proportionally the largest Hammerhead sharks (Sphyrnidae) exhibit a large amount of and measures up to 50% of their total body length (Lim et al., 2010). morphological variation within the family, making them the focus of In comparison, the bonnethead shark (Sphyrna tiburo) is the most many studies. The size of the laterally expanded head, or cephalofoil, is recently derived species and their cephalofoil width is 18% of total inversely correlated with pectoral fin area. The inverse relationship body length. Generally, as cephalofoil width increases among between cephalofoil and pectoral fin size in this family suggests that they species, pectoral fin area decreases (Thomson and Simanek, 1977). might serve a complementary role in lift generation. The cephalofoil is Previous studies on hammerhead sharks have focused primarily on also hypothesized to increase olfaction, electroreception and vision; cephalofoil morphology and its effects on hydrodynamics and however, little is known about how morphological variation impacts post- sensory efficiency; however, little is known about the morphology cranial swimming kinematics. Previous studies demonstrate that the and function of the post-cranial body. The significant bonnethead and scalloped hammerhead have significantly different yaw morphological variation and the close phylogenetic relationship amplitude, and we hypothesized that these species utilize varied among hammerheads make them an ideal study system to examine frequency and amplitude of undulation along the body. -
Sphyrna Tudes (Smalleye Hammerhead Shark)
UWI The Online Guide to the Animals of Trinidad and Tobago Ecology Sphyrna tudes (Smalleye Hammerhead Shark) Family: Sphyrnidae (Hammerhead Sharks) Order: Carcharhiniformes (Ground Sharks) Class: Chondrichthyes (Cartilaginous Fish) Fig. 1. Smalleye hammerhead shark, Sphyrna tudes. [http://otlibrary.com/wp-content/gallery/golden-hammerhead-shark/hammerhead-jeff-pierce-lo-res.jpg, downloaded 7 January 2015] TRAITS. One of the smaller species of hammerhead (Family Sphyrnidae), the smalleye hammerhead shark can reach a length of 1.5m and weigh around 9 kg. They have a streamlined, slender body as opposed to their bulkier relatives (Martin, 1999). Adult males may range from 110-130cm total length while adult females have an average length of 120-145cm. Newborns are usually about 30cm at birth. Common to all hammerhead sharks is the mallet/hammer shaped cephalofoil, which has a width of 28-32% of body length, and is wide and long. Newborns typically have a longer cephalofoil, which is more curved and with a smaller indent than that of adults (Castro, 1989). These hammerheads have considerably smaller eyes compared to that of other hammerheads, hence its name, and have tri-layered eyelids for protection. However the most distinctive trait being their golden coloration (Fig. 1), which gives the species other names like the golden hammerhead or the curry shark (Gallagher, 2010). Their colour may range from UWI The Online Guide to the Animals of Trinidad and Tobago Ecology bright gold to orange-yellow; however these colours only appear at the juvenile stage, usually when a length of 45cm is reached, and fade at sexual maturity (Castro, 1989). -
The Social Lives of Hammerheads. Authors: De Maddalena, Alessandro; Buttigieg, Alexander Publication: World and I Online Date: Jun 1, 2006
The social lives of hammerheads. Authors: De Maddalena, Alessandro; Buttigieg, Alexander Publication: World and I Online Date: Jun 1, 2006 Hammerhead sharks form the family of Sphyrnidae, that includes eight species: the winghead shark (Eusphyra blochii), scalloped bonnethead (Sphyrna corona), scalloped hammerhead (S. lewini), scoophead shark (S. media), great hammerhead (S. mokarran), bonnethead shark (S. tiburo), golden hammerhead (S. tudes) and the smooth hammerhead (S. zygaena). In the hammerhead shark, the front part of the head is flattened dorsoventrally and laterally increased to form what we call the "cephalofoil," or two wide flattened expansions that constitute the characteristic shape of a hammer. These two expansions are made out of muscular and connective tissues supported by a cartilaginous skeleton that is an integrated part of the skull. The round shaped eyes are placed very wide apart at the two lateral extremities of these expansions. Also placed at the front margin of these lateral expansions are the nostrils. The "hammer" or cephalofoil of the hammerheads unfolds into a series of functions correlated to the movement and the predation of these sharks. It has been observed that hammerhead sharks posses a very highly developed brain, and perhaps this could be the reason for the ability to lead the social life particular to these animals. Without a doubt, the most surprising aspect of socialization in hammerhead sharks is that of the immensely huge gatherings that different species form in numerous geographical areas. These gatherings could be formed from resident populations in that area or can be composed of individuals that migrate in masses. Huge gatherings of scalloped hammerhead sharks have been observed at the Sea of Cortez, near the Galapagos Island, near Cocos Island (Costa Rica), Malpelo (Columbia), and San Salvador (Bahamas), Hawaii, the Red Sea, Natal (South Africa), in Australia, the China Sea and near Cabilao Island (Philippines). -
Great Hammerhead Shark (Sphyrna Mokarran) UNDER the U.S
PETITION TO LIST THE Great Hammerhead Shark (Sphyrna mokarran) UNDER THE U.S. ENDANGERED SPECIES ACT Photo: Gary J. Wood (creative commons license) Petition Submitted to the U.S. Secretary of Commerce, Acting Through the National Oceanic and Atmospheric Administration and the National Marine Fisheries Service Petitioner: WildEarth Guardians 1536 Wynkoop Street, Suite 301 Denver, CO 80202 (303) 573-4898 December 18, 2012 INTRODUCTION WildEarth Guardians hereby formally petitions the Secretary of Commerce (Secretary), acting through the National Marine Fisheries Service (NMFS), an agency within the National Oceanic and Atmospheric Administration (NOAA), to list the great hammerhead shark (Sphyrna mokarran) as “threatened” or “endangered” under the U.S. Endangered Species Act (ESA) (16 U.S.C. §§ 1531-1544). We request that NMFS list the species throughout its range; however, in the alternative, if NMFS finds that there are Distinct Population Segments (DPS) of great hammerhead sharks, we would request that those be listed under the ESA. Additionally, we request that NMFS designate critical habitat for the species in U.S. waters or areas of the high seas that are essential to the species’ survival and recovery. The great hammerhead shark is the largest of all hammerhead sharks and is found in warm temperate and tropical waters around the world. Great hammerhead populations are in severe decline; the International Union for Conservation of Nature (IUCN) lists great hammerhead sharks as “endangered” on the IUCN Red List. IUCN Red List 2010a, Exhibit 1 at 1. The species faces at least five major threats. The first is the present and threatened destruction of great hammerhead habitat by pollution and anthropogenic climate change. -
Species Composition of the Largest Shark Fin Retail-Market in Mainland
www.nature.com/scientificreports OPEN Species composition of the largest shark fn retail‑market in mainland China Diego Cardeñosa1,2*, Andrew T. Fields1, Elizabeth A. Babcock3, Stanley K. H. Shea4, Kevin A. Feldheim5 & Demian D. Chapman6 Species‑specifc monitoring through large shark fn market surveys has been a valuable data source to estimate global catches and international shark fn trade dynamics. Hong Kong and Guangzhou, mainland China, are the largest shark fn markets and consumption centers in the world. We used molecular identifcation protocols on randomly collected processed fn trimmings (n = 2000) and non‑ parametric species estimators to investigate the species composition of the Guangzhou retail market and compare the species diversity between the Guangzhou and Hong Kong shark fn retail markets. Species diversity was similar between both trade hubs with a small subset of species dominating the composition. The blue shark (Prionace glauca) was the most common species overall followed by the CITES‑listed silky shark (Carcharhinus falciformis), scalloped hammerhead shark (Sphyrna lewini), smooth hammerhead shark (S. zygaena) and shortfn mako shark (Isurus oxyrinchus). Our results support previous indications of high connectivity between the shark fn markets of Hong Kong and mainland China and suggest that systematic studies of other fn trade hubs within Mainland China and stronger law‑enforcement protocols and capacity building are needed. Many shark populations have declined in the last four decades, mainly due to overexploitation to supply the demand for their fns in Asia and meat in many other countries 1–4. Mainland China was historically the world’s second largest importer of shark fns and foremost consumer of shark fn soup, yet very little is known about the species composition of shark fns in this trade hub2. -
Olfactory Morphology of Carcharhinid and Sphyrnid Sharks: Does the Cephalofoil Confer a Sensory Advantage?
JOURNAL OF MORPHOLOGY 264:253–263 (2005) Olfactory Morphology of Carcharhinid and Sphyrnid Sharks: Does the Cephalofoil Confer a Sensory Advantage? Stephen M. Kajiura,1* Jesica B. Forni,2 and Adam P. Summers2 1Department of Biological Sciences, Florida Atlantic University, Boca Raton, Florida 33431 2Ecology and Evolutionary Biology, University of California, Irvine, California 92697 ABSTRACT Many hypotheses have been advanced to eses fall into three categories: 1) enhanced olfactory explain the adaptive significance of the sphyrnid cephalo- klinotaxis, 2) increased olfactory acuity, and 3) foil, including potential advantages of spacing the olfac- larger sampling swath of the surrounding medium. tory organs at the distal tips of the broad surface. We To put these hypotheses into a quantifiable con- employed comparative morphology to test whether the text, consider the probability that an odorant mole- sphyrnid cephalofoil provides better stereo-olfaction, in- creases olfactory acuity, and samples a greater volume of cule binds to a receptor in the nasal rosette. The the medium compared to the situation in carcharhiniform number of odorant molecules that cross the olfactory sharks. The broadly spaced nares provide sphyrnid spe- epithelium is: cies with a significantly greater separation between the olfactory rosettes, which could lead to an enhanced ability N˙ (moles secϪ1) ϭ C(moles cmϪ3) to resolve odor gradients. In addition, most sphyrnid spe- 2 Ϫ1 cies possess prenarial grooves that greatly increase the An(cm )V(cm sec ) (1) volume of water sampled by the nares and thus increase the probability of odorant encounter. However, despite a where C is the concentration of odor molecules, An is much greater head width, and a significantly greater the area sampled by the naris, and V is the velocity number of olfactory lamellae, scalloped hammerhead of odorant over the olfactory rosette (Fig. -
Hammerhead Brochure
TEAM LEADERS Our female-led research team has been working together to promote research, conservation, and education opportunities for more than eight years. Dr. Catherine Macdonald Dr. Macdonald is a shark scientist and Lecturer in Marine Conservation Biology at the University of Miami’s Rosenstiel School of Marine and Atmospheric Science. She has more than 10 years of experience leading conservation-relevant shark research projects in South Florida and the southern Caribbean. Protecting an undiscovered Dr. Julia Wester Dr. Wester teaches Environmental nursery habitat for juvenile Policy at the Abess Center for Great Hammerhead Sharks Ecosystem Science and Policy at the University of Miami, and has worked (Sphyrna mokarran) as an environmental legislative aide for South Florida. She has been working on shark conservation EXECUTIVE SUMMARY issues since 2011, and will be leading policy and management proposals • There are no known nursery areas for the great hammerhead associated with this research. on the east coast of the United States. • Our woman-led research team has collected data demonstrating for the first time that juvenile hammerheads Visit NTOTA.org are present in the nearshore waters of southeastern Florida. • We are seeking funding for acoustic tags and receivers to to learn how to get involved identify key habitat and potential conservation threats. and support this project! • $30,000 has already been raised by NTOTA (NTOTA.org) to support the research and fund the creation of a short film by www.bluebackyardmiami.org National Geographic filmmakers. • This represents a potentially groundbreaking discovery with implications for how sharks are protected near the major urban center of Miami. -
Identifying Sharks and Rays
NSW DPI Identifying sharks and rays A guide for NSW commercial fishers Important If a shark or ray cannot be confidently identified using this guide, it is recommended that either digital images are obtained or the specimen is preserved. Please contact NSW DPI research staff for assistance: phone 1300 550 474 or email [email protected] Contents Introduction 4 How to use this guide 5 Glossary 6-7 Key 1 Whaler sharks and other sharks of similar appearance 8-9 to whalers – upper precaudal pit present Key 2 Sharks of similar appearance to whaler sharks – no 10 precaudal pit Key 3 Mackerel (great white and mako), hammerhead and 11 thresher sharks Key 4 Wobbegongs and some other patterned 12 bottom-dwelling sharks Key 5 Sawsharks and other long-snouted sharks and rays 13 2 Sandbar shark 14 Great white shark 42 Bignose shark 15 Porbeagle 43 Dusky whaler 16 Shortfin mako 44 Silky shark 17 Longfin mako 45 Oceanic whitetip shark 18 Thresher shark 46 Tiger shark 19 Pelagic thresher 47 Common blacktip shark 20 Bigeye thresher 48 Spinner shark 21 Great hammerhead 49 Blue shark 22 Scalloped hammerhead 50 Sliteye shark 23 Smooth hammerhead 51 Bull shark 24 Eastern angelshark 52 Bronze whaler 25 Australian angelshark 53 Weasel shark 26 Banded wobbegong 54 Lemon shark 27 Ornate wobbegong 55 Grey nurse shark 28 Spotted wobbegong 56 Sandtiger (Herbst’s nurse) shark 29 Draughtboard shark 57 Bluntnose sixgill shark 30 Saddled swellshark 58 Bigeye sixgill shark 31 Whitefin swellshark 59 Broadnose shark 32 Port Jackson shark 60 Sharpnose sevengill -
SHARK FACTS There Are 510 Species of Sharks
1 SHARK FACTS There are 510 species of sharks. Let’s learn more about a few of them. Common Six-gilled Thresher Shark Shark • Known for its 10 foot tail • Can grow up to 16 feet long • Stuns and herds fish with its long tail • Has six pairs of gills instead of the average of five • Warm blooded • Has one dorsal fin at the back of its body • Feeds on squid and schooling fish • Also known as cow shark or mud shark • Prefers to stay towards the top of deep bodies • Deep water shark of water Shortfin Great Mako Hammerhead Shark Shark • Bluish gray on top part of body and white on • Eyes are at opposite sides of its rectangular the belly shaped head • Has extremely sharp teeth, that stick out even when • Feeds on crustaceans, octopuses, rays and its mouth is shut small sharks • Feeds on sharks, swordfish and tuna • Usually found around tropical reefs • Jumps high in the air to escape fishing hooks • Can give birth to over 40 pups in one litter • Fastest of all the sharks as it can swim over 30 mph • Has a heigtened sense of electro-reception 2 SHARK FACTS Bull Nurse Shark Shark • Can grow up to 11 feet long and over 200 pounds • Has long, fleshy appendages called barbels that hang below its snout • Gray to brown in color with a white belly • Feeds on crab, lobster, urchins and fish • Feeds on fish, dolphins, sea turtles and other sharks • Usually found near rocky reefs, mudflats • Found in fresh and salt water and sandbars • Aggressive species • Enjoys laying on the ocean floor • Nocturnal animal Great Epaulette White Shark Shark • Can grow -
And Their Functional, Ecological, and Evolutionary Implications
DePaul University Via Sapientiae College of Science and Health Theses and Dissertations College of Science and Health Spring 6-14-2019 Body Forms in Sharks (Chondrichthyes: Elasmobranchii), and Their Functional, Ecological, and Evolutionary Implications Phillip C. Sternes DePaul University, [email protected] Follow this and additional works at: https://via.library.depaul.edu/csh_etd Part of the Biology Commons Recommended Citation Sternes, Phillip C., "Body Forms in Sharks (Chondrichthyes: Elasmobranchii), and Their Functional, Ecological, and Evolutionary Implications" (2019). College of Science and Health Theses and Dissertations. 327. https://via.library.depaul.edu/csh_etd/327 This Thesis is brought to you for free and open access by the College of Science and Health at Via Sapientiae. It has been accepted for inclusion in College of Science and Health Theses and Dissertations by an authorized administrator of Via Sapientiae. For more information, please contact [email protected]. Body Forms in Sharks (Chondrichthyes: Elasmobranchii), and Their Functional, Ecological, and Evolutionary Implications A Thesis Presented in Partial Fulfilment of the Requirements for the Degree of Master of Science June 2019 By Phillip C. Sternes Department of Biological Sciences College of Science and Health DePaul University Chicago, Illinois Table of Contents Table of Contents.............................................................................................................................ii List of Tables..................................................................................................................................iv -
Analysis of Data on Hammerhead Abundance, Distribution and Harvest in Australian Fisheries Since Implementation of the 2014 Hammerhead Shark Non-Detriment Finding
ANALYSIS OF DATA ON HAMMERHEAD ABUNDANCE, DISTRIBUTION AND HARVEST IN AUSTRALIAN FISHERIES SINCE IMPLEMENTATION OF THE 2014 HAMMERHEAD SHARK NON-DETRIMENT FINDING. Three species of hammerhead shark, scalloped hammerhead shark (Sphyrna lewini), great hammerhead shark (S. mokarran) and smooth hammerhead shark (S. zygaena), became listed under Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) in March 2013. The listings came into effect on 14 September 2014. Before an Appendix II listed species may be exported, the CITES Scientific Authority of the country of export must determine that the proposed export will not be detrimental to the survival of the species. This is referred to as a non-detriment finding (NDF). The Australian CITES Scientific Authority within the Department of Environment and Energy (the Department) made a non-detriment finding (NDF) covering hammerheads in September 2014. This NDF was published on the Department’s website and is available to the public1. The executive summary of the NDF states that it “is made for a period of three years from 14 September 2014 unless reviewed earlier”. This has set an expectation that the Australian CITES Scientific Authority will review the NDF in 2017. The NDF goes on to say “…if further information on individual species abundance, distribution and harvest becomes available through a review of trade data, ecological risk assessment or through research projects, the harvest levels contained in this NDF may be reviewed”. Harvest data and management information In August 2016 the Department contacted state, territory and Commonwealth fisheries agencies to determine if any additional information has been obtained on hammerhead shark distribution and abundance.