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The ISRA criteria take into account the complex biological and ecological needs of sharks. There are four criteria and seven sub-criteria. Important Shark and Ray Areas (ISRA) are discrete three-dimensional portions of habitat that are important for one or more species of chondrichthyans (sharks, rays and chimaeras) and have the potential to be managed for conservation. [1]
Rhina ancylostoma, also known as the bowmouth guitarfish, shark ray or mud skate, is a species of ray and a member of the family Rhinidae. Its evolutionary affinities are not fully resolved, though it may be related to true guitarfishes and skates .
Batoid gill slits lie under the pectoral fins on the underside, whereas a shark's are on the sides of the head. Most batoids have a flat, disk-like body, with the exception of the guitarfishes and sawfishes, while most sharks have a spindle-shaped body. Many species of batoid have developed their pectoral fins into broad flat wing-like appendages.
The value of shark fins for shark fin soup has led to an increase in shark catches where usually only the fins are taken, while the rest of the shark is discarded, typically into the sea; health concerns about BMAA in the fins now exists regarding consumption of the soup A 4.3-metre (14 ft), 540-kilogram (1,200 lb) tiger shark caught in Kāne ...
Sawfish were once common, with habitat found along the coastline of 90 countries, [102] locally even abundant, [4] [7] but they have declined drastically and are now among the most threatened groups of marine fish.
Guitarfish have a body form intermediate between those of sharks and rays. The tail has a typical shark-like form, but in many species, the head has a triangular, or guitar-like shape, rather than the disc-shape formed by fusion with the pectoral fins found in other rays.
Zone D, Shark Ray Alley, is a shallow sandy-bottomed area inside the reef, unremarkable except that it is a gathering place for sharks and stingrays. It was an area traditionally used by fishermen to clean their nets before returning to port, and the abundance of food that entered the water as a result attracted the sharks and rays to feed.
A pink manta ray has been observed in Australia's Great Barrier Reef and scientists believe this could be due to a genetic mutation causing erythrism. [23] The fish, spotted near Lady Elliot Island, is the world's only known pink manta ray. [24] [25] M. alfredi with mouth closed, cephalic fins rolled and ventral surface showing distinctive markings