RIVO-Netherlands Institute for Fisheries Research P.O. Box 68 P.O. Box 77 NL 1970 AB Ymuiden NL 4400 AB Yerseke The Netherlands The Netherlands Phone: +31 255 564646 Phone: +31 113 672300 Fax: +31 255 564644 Fax: +31 113 573477 Internet:[email protected] Internal RIVO report Number: 03.020 Identification document for large by-catch species in the Mauritanian Exclusive Economic Zone. R. ter Hofstede Project number: 3131230001 Date: November 2003 Number of copies: 10 Number of pages: 80 Number of tables: Number of figures: 2 Number of annexes: Since the first of June 1999 the foundation DLO (Agricultural Research Department) is no longer part of the Ministry of The management of the RIVO-Netherlands Institute for Fisheries Research accepts no responsibility for the follow-up Agriculture, Nature damage as well as detriment originating from the application of operational results, or other data acquired from the Management and Fisheries. RIVO-Netherlands Institute for Fisheries Research from third party risks in connection with this application. We are registered in trade register of the Chamber of This report is drafted at the request of the commissioner indicated above and is his property. Nothing from this report Commerce Centraal may be reproduced and/or published by print, photoprint microfilm or any other means without the previous written Amsterdam nr. 34135929 consent from the commissioner of the study. VAT nr. NL 808932184B09 Page 2 of 81 Internal RIVO report 03.020 Index Summary........................................................................................................................... 4 Order Tetradontiformes – Puffers and filefishes .................................................................... 5 Family Molidae – Molas .................................................................................................... 6 Order Perciformes - Billfishes .............................................................................................. 7 Family Istiophoridae – Perch-likes...................................................................................... 8 Family Xiphias gladius – Swordfishes............................................................................... 12 Order Hexanchiformes – Frilled and Cow sharks ................................................................. 13 Family Chlamydoselachidae – Frilled sharks ..................................................................... 14 Family Hexanchidae – Cowsharks, Sixgill sharks, Sevengill sharks ..................................... 15 Order Squaliformes – Dogfish sharks................................................................................. 16 Family Echinorhinidae – Bramble sharks .......................................................................... 17 Family Squalidae – Dogfish sharks .................................................................................. 18 Family Oxynotidae – Rough sharks .................................................................................. 25 Order Squatiniformes – Angelsharks .................................................................................. 26 Family Squatinidae – Angelsharks, Sand devils................................................................. 27 Order Orectolobiformes – Carpet sharks............................................................................ 30 Family Rhiniodontidae – Whale sharks.............................................................................. 31 Order Lamniformes – Mackerel sharks.............................................................................. 32 Family Odontaspididae – Sand tiger sharks...................................................................... 33 Family Alopiidae – Thresher sharks ................................................................................. 34 Family Lamnidae – Mackerel sharks, Porbeagles, White sharks ......................................... 35 Order Carcharhiniformes – Ground sharks.......................................................................... 37 Family Scyliorhinidae - Catsharks .................................................................................... 38 Family Pseudotriakidae – False catsharks ........................................................................ 41 Family Leptochariidae – Barbeled houndsharks ................................................................ 42 Family Triakidae – Houndsharks ...................................................................................... 43 Family Hemigaleidae – Weasel sharks ............................................................................. 45 Family Carcharhinidae - Requiem sharks .......................................................................... 46 Family Sphyrnidae – Bonnethead sharks, Hammerhead sharks, Scoophead sharks............. 55 Order Cetacea ................................................................................................................. 59 Suborder Mysticeti - Baleen Whales................................................................................. 59 Family Balaenopteridae .................................................................................................. 60 Internal RIVO report 03.020 Page 3 of 81 Suborder Odontoceti - Toothed whales.............................................................................63 Family Physeteridae........................................................................................................64 Family Kogiidae ..............................................................................................................65 Family Ziphiidae..............................................................................................................66 Family Delphinidae..........................................................................................................67 Family Phocoenidae ........................................................................................................77 References.......................................................................................................................78 Page 4 of 81 Internal RIVO report 03.020 Summary The coastal waters of Mauritania (Northwest Africa) contain large numbers of pelagic fish such as sardinella, sardine, mackerel and horse mackerel. Freezer-trawlers from the European Union (EU), mainly of Dutch origin, have exploited these resources since 1996. In 1998 the Dutch ship owners commissioned a study by the Netherlands Institute for Fisheries Research (ASG-WUR) into the long-term potential of pelagic species in this area. This study has gradually expanded into a joint research project with the Mauritanian Institute for Research on Oceanography and Fishery (IMROP), funded by the Dutch government. In order to collect precise and reliable data the catch of the EU pelagic trawlers, a scientific observer program was established. Observers record species composition of catches and discards, and they collect biological information on the target species. In addition they monitor accidental by-catches of large animals such as rays, sharks and dolphins. The purpose of this document is to facilitate the determination of these large by-catch species. From FAO identification guides, a selection has been made of species that are potentially present in the Mauritanian Exclusive Economic Zone. For each species, a picture and a brief description of the characteristics are given. Internal RIVO report 03.020 Page 5 of 81 Order Tetradontiformes – Puffers and filefishes Page 6 of 81 Internal RIVO report 03.020 Family Molidae – Molas Mola mola (Linnaeus, 1758) Synonyms: Tetraodon mola, Orthragoriscus mola, Diodon mola, Mola rotunda, Aledon capensis Common names: En- Ocean sunfish; Fr- Poisson-lune; NL- Maanvis Body characteristics: Striking body shape, body high, lateral compressed. Terminal small mouth, parrot-like beak. Body covered with extremely thick, elastic skin. Dorsal and anal fins very high with short base; pectorals small and rounded, directed upward. Caudal fin replaced by a rudder-like structure (clavus). Colour: - Size: adults up to 333 cm TL. Internal RIVO report 03.020 Page 7 of 81 Order Perciformes - Billfishes Page 8 of 81 Internal RIVO report 03.020 Family Istiophoridae – Perch-likes Istiophorus albicans (Latreille, 1804) Synonyms: Histiophorus americanus, Histiophorus pulchellus, Makaira velifera, Skeponopodus guebucu, Histiophorus granulifer, Xiphias velifer, Istiophorus americanus, Istiophorus wrightii, Istiophorus maguirei, Istiophorus volador, Histiophorus albicans Common names: En- Atlantic sailfish; Fr- Voilier de l’Atlantique; NL- Zeilvis Body characteristics: Body fairly compressed. Bill long, slender and round in cross section. Two dorsal fins; first dorsal fin sail-like and remarkably higher than greatest body depth, base long and close to that of small second dorsal fin. Pelvic fins very long, nearly reaching the anus. Two anal fins, position of the second slightly more forward than second dorsal fin. Colour: Body dark blue dorsally, light blue splattered with brown laterally, and silvery white ventrally. About 20 rows of longitudinal stripes on sides, each stripe composed of many light blue round dots. Bases of first and second anal fins often tinged with silvery white; membrane of first dorsal fin dark blue or blackish blue, with scattered small round black dots; remaining fins blackish blue, sometimes tinged with dark brown. Size: adults 150-210 cm BL, up