For the complete list of news visit us on facebook.
Many thanks to Kazuhiro Nakaya for this link and the attached information about a new record of #Megachasma pelagios! One hundred and eleventh #megamouth shark (based on my personal data) was caught in Japan. She was kept in a large offshore pen, but disappointedly died. You can reach its information from following url. http://www.asahi.com/ajw/articles/AJ201705230049.html http://shark-references.com/species/view/Megachasma-pelagios
Thanks to Julia Spät for this new paper! The Arabian Seas Region plays an important role in the global landings and trade of sharks and rays. The United Arab Emirates (UAE) and Yemen, two countries with stark socio-economic differences, serve as major regional trade hubs for shark and ray products and four countries (Oman, Pakistan, UAE and Yemen) supply nearly 11% of dried fin exports to Hong Kong. Yet, little information is available on the characteristics of this trade and the fisheries contributing to it. Here, we review the fisheries characteristics, trade, utilization and distribution chain of sharks and rays in 15 countries of the Arabian Seas Region based on published and grey literature, landing surveys, field observations and interviews with fishermen and traders. Jabado RW, Spaet JLY. Elasmobranch fisheries in the Arabian Seas Region: Characteristics, trade and management. Fish Fish. 2017;00:1–23 http://onlinelibrary.wiley.com/wol1/doi/10.1111/faf.12227/abstract
Thanks to Sue Carney (https://www.facebook.com/sue.carney1) for the new paper about Summer-Resident Cownose Rays! The authors used genetics to characterize Cownose Rays from three locations in the Chesapeake Bay in an effort to better understand their population structure. CARNEY, S.L. & MCVEIGH, D.M. & MOSS, J.B. & FERRIER, M.D. & MORRISSEY, J.F. 2017 Insights on Mitochondrial Genetic Variation in Chesapeake Bay Summer-Resident Cownose Rays. Transactions of the American Fisheries Society, 146 (3): 478-484 http://www.tandfonline.com/doi/abs/10.1080/00028487.2017.1285350?journalCode=utaf20 http://shark-references.com/species/view/Rhinoptera-bonasus image: #Rhinoptera bonasus (MITCHILL, 1815), © Andy Murch, Elasmodiver.com
Anthony J Richardson sent me a new paper about the reef manta ray (Manta alfredi, now valid as Mobula alfredi)! The preserved stomach contents from the manta ray, collected in 1935, that provided the basis for the 2009 taxonomic resurrection of the species Manta alfredi, were examined. The majority of the material comprised calanoid copepods (61.7%) and trypanorhynch cestodes (34.6%), with minor contributions by arrow worms, a barnacle larva and a nematode. BENNETT, M.B. & COMAN, F.F. & TOWNSEND, K.A. & COUTURIER, L.I.E. & JAINE, F.R.A. & RICHARDSON, A.J. 2017 A historical and contemporary consideration of the diet of the reef manta ray (Manta alfredi) from the Great Barrier Reef, Australia. Marine and Freshwater Research, 68 (5): 993-997 http://www.publish.csiro.au/mf/MF16046 http://shark-references.com/species/view/Mobula-alfredi image: #Mobula alfredi (KREFFT, 1868), © Dr. Csilla Ari
Thanks to Audrey Schlaff for this new paper about blacktip reef sharks (Carcharhinus melanopterus). Passive acoustic telemetry was used to monitor movement and space use of 18 blacktip reef sharks #Carcharhinus melanopterus on an inshore reef off the coast of Queensland, #Australia, to determine their response to environmental change. SCHLAFF, A.M. & HEUPEL, M.R. & UDYAWER, V. & SIMPFENDORFER, C.A. 2017 Biological and environmental effects on activity space of a common reef shark on an inshore reef. Marine Ecology Progress Series, 571: 169–181 http://www.int-res.com/abstracts/meps/v571/p169-181/ http://shark-references.com/species/view/Carcharhinus-melanopterus image: Carcharhinus melanopterus (QUOY & GAIMARD, 1824); Shin Sirachai Arunrugstichai, Center for Biodiversity in Peninsular Thailand, Yai Songkla, Thailand
New described shark species (no. 527! Elasmobranchs altogether: 1223; chimaeras: 53; rays/skates: 643) :-) Thanks to Simon Weigmann for this new paper and the new images of the holotype! A new very small deep-water catshark, Bythaelurus vivaldii, is described based on two female specimens caught off Somalia in the northwestern Indian Ocean during the German ‘Valdivia’ expedition in 1899. It is morphologically closest to the recently described B. bachi, which is the only other Bythaelurus species in the western Indian Ocean that shares a stout body of large specimens and the presence of oral papillae. WEIGMANN, S. & KASCHNER, C.J. 2017 Bythaelurus vivaldii, a new deep-water catshark (Carcharhiniformes, Scyliorhinidae) from the northwestern Indian Ocean off Somalia. Zootaxa, 4263 (1): 07–119 http://www.mapress.com/j/zt/article/view/zootaxa.4263.1.4 http://shark-references.com/species/view/Bythaelurus-vivaldii
Thanks to Maximilian Hirschfeld for the link to this new paper! 😃 Please support our project and inform us about new or missing (which is indicated by the missing info symbol at the citation) paper or send us your images! 🙂 PAZMIÑO, D.A. & MAES, G.E. & SIMPFENDORFER, C.A. & SALINAS-DE-LEÓN, P. & VAN HERWERDEN, L. 2017 Genome-wide SNPs reveal low effective population size within confined management units of the highly vagile Galapagos shark (Carcharhinus galapagensis). Conservation Genetics, in press https://link.springer.com/article/10.1007/s10592-017-0967-1 The authors examined stock structure, connectivity and effective population size of Galapagos sharks among GMR locations using genome-wide neutral Single Nucleotide Polymorphism (8103 SNP) and mtDNA markers. http://shark-references.com/species/view/Carcharhinus-galapagensis
Enjoy this Video of Odontaspis ferox! http://shark-references.com/species/view/Odontaspis-ferox
The press release to the #Angelsharkproject paper! https://angelsharkproject.com/2017/05/15/press-release-saving-angels-vital-information-on-angelshark-ecology-used-to-inform-the-conservation-of-one-of-europes-most-endangered-sharks/
New study on the #CriticallyEndangered #Angelshark in the Canary Islands using #CitizenScience data! Thanks a lot to Eva MEyers for this new paper and the permissions to use the attached image! Meyers EKM, Tuya F, Barker J, et al. Population structure, distribution and habitat use of the Critically Endangered Angelshark, Squatina squatina, in the Canary Islands. Aquatic Conserv: Mar Freshw Ecosyst. 2017. https://doi.org/10.1002/aqc.2769 http://shark-references.com/species/view/Squatina-squatina
Reef sharks may influence the foraging behaviour of mesopredatory teleosts on coral reefs via both risk effects and competitive exclusion. We used a “natural experiment” to test the hypothesis that the loss of sharks on coral reefs can influence the diet and body condition of mesopredatory fishes by comparing two remote, atoll-like reef systems, the Rowley Shoals and the Scott Reefs, in northwestern Australia. open access! BARLEY, S.C. & MEEKAN, M.G. & MEEUWIG, J.J. 2017 Diet and condition of mesopredators on coral reefs in relation to shark abundance. PLoS ONE, 12 (4): e0165113 http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0165113 http://shark-references.com/species/view/Carcharhinus-albimarginatus image: Carcharhinus albimarginatus (RÜPPELL, 1837), © FAO, Food and Agriculture Organization of the United Nations, Ebert, D.A. 2014. On Board Guide for the Identification of Pelagic Sharks and Rays of the Western Indian Ocean. Reproduced with permission, illustration by Marc Dando, Wildlife Illustrator
open access! The Pacific spiny dogfish, Squalus suckleyi, is a small shark species commonly found in the North Pacific Ocean. Age determination for this species has historically been conducted by examination of the dorsal fin spine with little change in methodology since the 1930’s. Somebody who could share some images of Squalus suckleyi for our database (email@example.com) TRIBUZIO, C.A. & MATTA, M.E. & GBURSKI, C. & ATKINS, AN. & BUBLEY, W. 2016 Methods for the Preparation of Pacific Spiny Dogfish, Squalus suckleyi, Fin Spines and Vertebrae and an Overview of Age Determination. Marine Fisheries Review, 78 (1-2): 1-13 http://spo.nmfs.noaa.gov/sites/default/files/pdf-content/mfr781-21.pdf http://shark-references.com/species/view/Squalus-suckleyi
Thanks to Chris Wood for his paper "Feeding through your gills and turning a toxicant into a resource: how the dogfish shark scavenges ammonia from its environment" Chris M. Wood and Marina Giacomin Nitrogen appears to be a limiting dietary resource for elasmobranchs, required not only for protein growth but also for urea-based osmoregulation. Building on recent evidence trat the toxicant ammonia can be taken up actively at the gills of the shark and made into the valuable osmolyte urea, we demonstrate that the uptake exhibits classic Michaelis–Menten saturation kinetics with an affinity constant (Km) of 379 μmol l−1, resulting in net N retention at environmentally realistic ammonia concentrations (100–400 μmol l−1) and net N loss through stimulated urea-N excretion at higher levels. http://shark-references.com/species/view/Squalus-suckleyi Image: Squalus acanthias LINNAEUS, 1758, Rhode Island, USA © Fredrik Akerman Common names
Enjoy the amazing images of the National Geographic Staff!
Dr. William Robbins sent me his new paper! It deals with 38 species, nine of which are elasmobranch. There’s a free download available at https://authors.elsevier.com/a/1U-7T,714MRQMm for the next 40 days too. Thanks a lot for the support! Highlights • Expert elucidation assessed anthropogenic threats to 38 marine-associated species. • Climate change was deemed the greatest threat across most species. • Disturbance and pollution threats were the largest regional threats. • Mammals were the most vulnerable group, with elasmobranchs comparatively data-poor. • Five species were consistently the most vulnerable across threats. Abstract Marine Policy, Volume 81, July 2017, Pages 392–400 Anthropogenic threat assessment of marine-associated fauna in Spencer Gulf, South Australia William D. Robbins, Charlie Huveneers, Guido J. Parra, Luciana Möller, Bronwyn M. Gillanders Image: (LESUEUR, 1818), © Steve Garner http://shark-references.com/species/view/Carcharhinus-obscurus
Many thanks to Ana Hacohen for the amazing image and the information about this open access paper! This study forms the first confirmed records of the sharpnose sevengill shark Heptranchias perlo in Guatemala’s Caribbean Sea and increase the number of known shark species in Guatemala. Hacohen-Domené, A., Polanco-Vásquez, F., & Graham, R.T. 2017. First record of Heptranchias perlo (Bonnaterre 1788) in Guatemala’s Caribbean Sea. Marine Biodiversity Records.10:12 https://mbr.biomedcentral.com/articles/10.1186/s41200-017-0118-x http://shark-references.com/species/view/Heptranchias-perlo
Historically, the knowledge of sharks (Elasmobranchii) has always lagged far behind the knowledge of bony fishes and other vertebrates. In the 1950’s, only a handful of researchers were working with or studying sharks. But, in the second half of the 20th century, four factors combined to spark interest in sharks, make shark research feasible, and engender shark biology and conservation. open access CASTRO, J. 2016 The Origins and Rise of Shark Biology in the 20th Century. Marine Fisheries Review, 78 (1-2): 14-33 http://spo.nmfs.noaa.gov/sites/default/files/pdf-content/mfr781-22.pdf http://shark-references.com/species/view/Carcharodon-carcharias
Thanks to Lius Lucifora for his new paper on freshwater stingrays and images of Potamotrygon amandae http://shark-references.com/species/view/Potamotrygon-amandae. Decline or stability of obligate freshwater elasmobranchs following highfishing pressure. Despite elasmobranchs are a predominantly marine taxon, several species of sharks and rays are regularly found in fresh water. Although there is ample evidence of declining elasmobranch populations around the world, this evidence comes exclusively from marine and euryhaline species; the ecology and conservation status of obligate freshwater elasmobranchs is far from being understood. River stingrays (Potamotrygoninae, 32 species) live exclusively in South American rivers and represent the overwhelming majority of freshwater elasmobranch diversity. Here, we present evidence of a decline in the abundance of river stingrays in the middle and lowerParaná River, an extensive wetland mosaic of approximately 35,000 km 2 . http://www.sciencedirect.com/science/article/pii/S0006320716310394?via%3Dihub Luis O. Lucifora , Leandro Balboni , Pablo A. Scarabotti, Francisco A. Alonso,David E. Sabadin, Agustín Solari, Facundo Vargas, Santiago A. Barbini,Ezequiel Mabragaña, Juan M. Díaz de Astarloa image: Potamotrygon amandae. The picture was taken in the Corriente River, a tributary of the Paraná River in Argentina. Credit by Matías A. Lipsker
Many thank's to Claudio Barría for this new paper! Marine Pollution Bulletin, in press, doi:10.1016/j.marpolbul.2017.04.021 Carboxylesterase activities in chondrichthyans of the western Mediterranean Sea by David Nos, Joan Navarro, Claudio Barría, Montserrat Solé Highlights • Chondrichthyans show differences in their carboxylesterases values. • The substrate αNA is more adequate for carboxylesterase measures in chondrichthyans. • Shark plasma has high carboxylesterase activity and do not require animal sacrifice. • Chondrichthyans could serve as sentinels of xenobiotics in the ecosystem. http://www.sciencedirect.com/science/article/pii/S0025326X17303284 Image: Scyliorhinus canicula (LINNAEUS, 1758) Staatliches Museum für Naturkunde Karlsruhe, Germany, © H. Zell,
New update for our project Toothmorphology (http://shark-references.com/post/523)! Please support this project and sent us images and/or teeth/jaws of missing species (firstname.lastname@example.org)! We just added images of Squatina californica AYRES, 1859 (http://shark-references.com/post/713) Squatina dumeril LESUEUR, 1818 (http://shark-references.com/post/714) Squatina squatina (LINNAEUS, 1758) (http://shark-references.com/post/715) Thanks to Ross Robertson, Smithsonian Tropical Research Institute, Panama and Jacques Herman for the images!
Highlights • Tiger, Blue, and White Sharks have teeth with unique serration morphologies. • Tiger Sharks have histologically distinct primary and secondary serrations. • Secondary serrations of Tiger Sharks increase the pitch of the cutting edge. • Conical tooth serrations complicate analogies to manufactured cutting tools. MOYER, J.K. & BEMIS, W.E. 2017 Shark teeth as edged weapons: serrated teeth of three species of selachians. Zoology, 120: 101-109 http://www.sciencedirect.com/science/article/pii/S0944200616300320 images by Jürgen Pollerspöck, www.shark-references.com
Samples of the shovelnose guitarfish Pseudobatos productus were collected on board a vessel and at landings of artisanal commercial fisheries in the Gulf of California from May 2004 to June 2007. Samples of 650 females, 2047 embryos and 484 uterine eggs were examined. The reproductive cycle is annual, ovulation and parturition occur in July, the uterine eggs are in diapause for 9 months (July–March) before an accelerated growth of embryos of 3 months. ROMO-CURIEL, A.E. & SOSA-NISHIZAKI, O. & PEREZ-JIMENEZ, J.C. & RODRIGUEZ-MEDRANO, M.C. 2017 Reproductive cycle and maternal-embryonic nutritional relationship of shovelnose guitarfish Pseudobatos productus in the Gulf of California. Journal of Fish Biology, 90 (3): 889-905 http://onlinelibrary.wiley.com/doi/10.1111/jfb.13204/full http://shark-references.com/species/view/Pseudobatos-productus image: Pseudobatos productus (AYRES, 1854), © Centro Interdisciplinario de Ciencias Marinas (CICIMAR-IPN) http://coleccion.cicimar.ipn.mx
Hurra, hurra and many thanks to our webmaster and programmer @Philipp Friedenberger Sharks-references is back online!
Dear friends of sharks references. Our website is at the moment offline. We have a unknown problem with our server. Our webmaster try to solve this problem as soon as possible. Sorry for the discomfort.
open access! An assessment of scalloped (Sphyrna lewini) and great (Sphyrna mokarran) hammerhead population structure and connectivity across northern Australia, Indonesia and Papua New Guinea (PNG) was conducted to inform management responses to CMS and Convention on International Trade in Endangered Species listings of these species. CHIN, A. & SIMPFENDORFER, C.A. & WHITE, W.T. & JOHNSON, G.J. & MCAULEY, R.B. & HEUPEL, M.R. 2017 Crossing lines: a multidisciplinary framework for assessing connectivity of hammerhead sharks across jurisdictional boundaries. Scientific Reports, 7: 46061 file:///C:/Users/beate-juergen/Downloads/srep46061.pdf http://shark-references.com/species/view/Sphyrna-lewini http://shark-references.com/species/view/Sphyrna-mokarran image: Sphyrna lewini (GRIFFITH & SMITH, 1834), © Randall, J.E. and by the authors
For the complete list of news visit us on facebook.