The key to surviving hypoxia is to protect the brain from energy depletion. The epaulette shark (Hemiscyllium ocellatum) is an elasmobranch able to resist energy depletion and to survive hypoxia. Using epi-illumination microscopy in vivo to observe cerebral blood flow velocity on the brain surface, we show that cerebral blood flow in the epaulette shark is unaffected by 2 h of severe hypoxia (0...

in a parasitic study on five sharks (carcharhinus macloti) caught from the iranian coasts of persian gulf, two of five sharks appeared to have nematode in their intestine. using light microscopy, the nematode was identified as acanthocheilus rotundatus. a. rotundatus  is characterised by 3.3-4.5 cm in length, semithick cuticle, small lips, semicircular and tri-lobed pseudolabia (not offset from...

Unravelling the genetic structure and phylogeographic patterns of deep-sea sharks is particularly challenging given the inherent difficulty in obtaining samples. The deep-sea shark Centroscymnus crepidater is a medium-sized benthopelagic species that exhibits a circumglobal distribution occurring both in the Atlantic and Indo-Pacific Oceans. Contrary to the wealth of phylogeographic studies foc...

Accurately surveying shark populations is critical to monitoring precipitous ongoing declines in shark abundance and interpreting the effects that these reductions are having on ecosystems. To evaluate the effectiveness of existing survey tools, we used field trials and computer simulations to critically examine the operation of four common methods for counting coastal sharks: stationary point ...

The blue shark (Prionace glauca) is a large pelagic carcharhinid that is widely distributed in the world’s oceans. Throughout its range, it is considered the most abundant species of large shark (McKenzie and Tibbo, 1964; Casey, 1982). In the Atlantic, the blue shark is distributed from Newfoundland to Argentina in the west and Norway to South Africa, including the Mediterranean, in the east (C...

Bycatch (the unintentional catch of non-target species or sizes) is consistently ranked as one of the greatest threats to marine fish populations; yet species-specific rates of bycatch survival are rarely considered in risk assessments. Regulations often require that bycatch of threatened species be released; but, if animals are already dead, their release serves no conservation purpose. We exa...

All 13 orders of chondrichthyan fishes occur in Taiwanese waters, representing 52 chondrichthyan families (31 shark, 19 batoid, 2 chimaeroid) and 98 genera (64 shark, 31 batoid, 3 chimaeroid). A total of 119 shark, 58 batoid, and 4 chimaera species may occur in the waters surrounding Taiwan, pending taxonomic resolution of some groups. Of the 34 nominally described species from Taiwan, 17 are c...

Overfishing is arguably the greatest ecological threat facing the oceans, yet catches of many highly migratory fishes including oceanic sharks remain largely unregulated with poor monitoring and data reporting. Oceanic shark conservation is hampered by basic knowledge gaps about where sharks aggregate across population ranges and precisely where they overlap with fishers. Using satellite tracki...

The discovery that angiogenesis is a key condition for the growth of a tumor beyond a millimeter or two, brings about a new approach in the treatment of tumors using drugs able to inhibit the formation of new blood vessels. Also, it has been realized that antiangiogenic drugs can be useful in the treatment of other pathological processes, now classified as angiogenesis-dependent diseases. Initi...