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Some observations on the reproductive biology of The sixgill shark Hexanchus griseus (Bonnaterre, 1788) from southern African waters
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: D. A. EbertObservations are made of the maturation status of 81 male and 88 female sixgill sharks Hexanchus griseus from southern African waters. Males mature at about 310 cm total length (TL) with the calcification of the terminal cartilage elements of the... -
Influence of the annual sardine run on catches of large sharks in the protective gillnets off KwaZulu-Natal, South Africa, and the occurrence of sardine in shark diet
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SFJ Dudley --- , South Africa G Cliff --- , South AfricaShark catches in the protective nets set off the beaches of KwaZulu-Natal (KZN), South Africa, are strongly influenced by the sardine run, the winter influx of shoals of Sardinops sagax from the south-west. The effect of the sardine run, which... -
Distribution and movement of scalloped hammerhead Sphryna lewini and smooth hammerhead Sphyrna zygaena sharks along the east coast of southern Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: KM Diemer --- Great Lakes Institute of Environmental Research, Canada BQ Mann --- , South Africa NE Hussey --- Great Lakes Institute of Environmental Research, CanadaKnowledge of population distribution and movement is crucial for the conservation and management of shark species occurring in coastal waters. From 1984 to 2009, 641 scalloped hammerheads Sphyrna lewini, 1 342 smooth hammerheads Sphyrna zygaena and 1 352 unspecified hammerheads... -
A first description of the artisanal shark fishery in northern Madagascar: implications for management
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L Robinson --- Department of Ichthyology and Fisheries Science, South Africa WHH Sauer --- Department of Ichthyology and Fisheries Science, South AfricaIn the past two decades, small, targeted artisanal shark fisheries have developed in the extreme north of Madagascar, largely in response to the shark fin trade. Few studies have been undertaken to assess the biological characteristics and impact of these... -
A preliminary study of allozyme differences amongst Carcharhinus sharks from the continental slope near Abidjan, Côte d'lvoire
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Béatrice Adepo-Gourène Lounès Chikhi Jean-François Agnèse Germain Gourène Alain HervéGenetic variability of fifty-five shark specimens from the genus Carcharhinus was analysed using 18 allozyme loci. Sixteen loci were polymorphic either within, or between, species. Levels of genetic polymorphism, as measured by observed heterozygosity values, ranged from 0.008 (±0.008) to... -
Pelagic shark bycatch in the tuna- and swordfish-directed longline fishery off southern Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SL Petersen --- , South Africa MB Honig --- , South Africa PG Ryan --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute of African Ornithology, South Africa LG Underhill --- Animal Demography Unit, Department of Zoology, South Africa LJV Compagno --- , South AfricaThe capture of pelagic sharks as bycatch of the South African pelagic longline fleet targeting tuna Thunnus spp. and swordfish Xiphias gladius was investigated during the period 1998-2005. In all, 26 species were caught, of which six are listed by... -
White shark (Carcharodon carcharias)-inflicted bite wounds observed on Cape fur seals (Arctocephalus pusillus pusillus) at Black Rocks, Algoa Bay, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Matthew L. Dicken --- KwaZulu-Natal Sharks Board, South Africa Michelle Bradshaw --- Port Elizabeth Museum, South Africa Malcolm J. Smale --- Port Elizabeth Museum, South AfricaThis paper presents the first quantitative study on the seasonal occurrence and body location of white shark (Carcharodon carcharias)-inflicted injuries on Cape fur seals (Arctocephalus pusillus pusillus) at Black Rocks, in Algoa Bay. Between January 2010 and October 2011, 22... -
The evolution of chondrichthyan research through a metadata analysis of dedicated international conferences between 1991 and 2014
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: C Huveneers --- School of Biological Sciences, Flinders University, Australia DA Ebert --- Pacific Shark Research Center, Moss Landing Marine Laboratories, USA SFJ Dudley --- Branch: Fisheries Management, Department of Agriculture, South AfricaScience is continually evolving, with recent developments in some fields, such as conservation biology, leading to shifts in priorities and needs. Recent international conferences focused on chondrichthyan research provide an opportunity to assess how the research environment of chondrichthyan science... -
Molecular species identification and population genetics of chondrichthyans in South Africa: current challenges, priorities and progress
Item type: Journal Article • Journal: African Zoology • Authors: Aletta E Bester-van der Merwe --- Molecular Breeding and Biodiversity Group, Department of Genetics, South Africa Katie S Gledhill --- South African Shark Conservancy, South AfricaMolecular genetic techniques, such as DNA barcoding and genotyping, are increasingly being used to assist with the conservation and management of chondrichthyans worldwide. Southern Africa is a shark biodiversity hotspot, with a large number of endemic species. According to the... -
Reflection on the first five years of South Africa’s Acoustic Tracking Array Platform (ATAP): status, challenges and opportunities
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: PD Cowley --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa RH Bennett --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa A-R Childs --- Department of Ichthyology and Fisheries Science, South Africa TS Murray --- South African Institute for Aquatic Biodiversity (SAIAB), South AfricaThe Acoustic Tracking Array Platform (ATAP) is a marine science programme that monitors the movements and migrations of inshore marine animals along the South African coastline. Acoustically tagged animals are monitored by an expanded network of approximately 100 automated data-logging... -
Using mark-recapture methods to estimate population size and survival of pyjama sharks Poroderma africanum in Mossel Bay, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SP Grusd --- Department of Biological Sciences and the Marine Research Institute, South Africa CL Moloney --- Department of Biological Sciences and the Marine Research Institute, South Africa G Distiller --- Statistics in Ecology, Environment and Conservation (SEEC), Department of Statistical Sciences, South Africa RGA Watson --- Oceans Research, South Africa PD Cowley --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa E Gennari --- Oceans Research, South AfricaThe pyjama shark Poroderma africanum (family Scyliorhinidae) is endemic to coastal waters of South Africa but its population characteristics are poorly known. This study aims to estimate baseline demographic parameters for P. africanum in Mossel Bay. We applied mark-recapture methods... -
All washed up: spatial and temporal variation in the wash-up and fate of chondrichthyan egg cases along a section of the Garden Route, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: S Schmöle --- , The Netherlands M Brown --- , South Africa M Witteveen --- , South AfricaWashed-up chondrichthyan egg cases were collected along three different sandy beaches around Plettenberg Bay, South Africa, between April 2016 and March 2017. GPS location was recorded upon collection, and, after being soaked in fresh water for 12 hours, egg cases... -
Distribution and community structure of at-risk and Data Deficient elasmobranchs in Zavora Bay, Mozambique
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: B O’Connor --- , The Netherlands N Cullain --- , United StatesPersistent threats from fishing pressure and increasing habitat degradation, as well as slow recovery rates resulting from K-selected life histories, are putting increasing numbers of elasmobranch species (sharks, rays and skates) at risk of extinction worldwide. Global declines in elasmobranch... -
Further insights into killer whales Orcinus orca preying on white sharks Carcharodon carcharias in South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Towner --- Rhodes University, South Africa P Micarelli --- University of Siena, Italy D Hurwitz --- , South Africa MJ Smale --- Nelson Mandela University, South Africa AJ Booth --- Rhodes University, South Africa C Stopforth --- , South Africa E Jacobs --- , South Africa FR Reinero --- Sharks Studies Centre – Scientific Institute, Italy V Ricci --- Sharks Studies Centre – Scientific Institute, Italy A Di Bari --- Sharks Studies Centre – Scientific Institute, Italy S Gavazzi --- Sharks Studies Centre – Scientific Institute, Italy G Carugno --- Sharks Studies Centre – Scientific Institute, Italy M Mahrer --- Claremont McKenna College, United States E Gennari --- Rhodes University, South AfricaPhotography and video footage, captured by researchers and tourists on board two vessels, provided insights into the predation techniques employed by an adult male killer whale Orcinus orca in Mossel Bay, South Africa. The incapacitation of its prey, a juvenile... -
Movement and growth of the spotted gully shark Triakis megalopterus in South African waters
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: BQ Mann --- Oceanographic Research Institute (ORI), South Africa GL Jordaan --- Oceanographic Research Institute (ORI), South Africa WN Dalton --- Oceanographic Research Institute (ORI), South Africa R Daly --- Oceanographic Research Institute (ORI), South Africa M Soekoe --- Reel Science Coalition, South Africa WM Potts --- Rhodes University, South Africa MJ Smale --- Zoology Department and Institute for Coastal and Marine Research, Nelson Mandela University, South Africa L Swart --- Fisheries and the Environment (DFFE), South AfricaThe movement and growth of spotted gully sharks Triakis megalopterus (family Triakidae) along the coast of South Africa were investigated using external dart tagging. Of a total of 7 211 sharks tagged, 657 (9.1%) were recaptured over a 37-year period,...