Common eagle ray


The common eagle ray is a species of fish in the family Myliobatidae. It inhabits the eastern Atlantic Ocean, the Mediterranean Sea and the south-western Indian Ocean.

Description

The common eagle ray reaches up to in total length and has a disc width up to. It has a rhomboidal disc with a pair of large, triangular pectoral fins projecting on either side, and a single dorsal fin. The snout is rounded and the tail slender, with a large spine at its base but no tail fin. The dorsal surface is brown or black while the ventral surface is white.

Distribution and habitat

This ray occurs in the eastern Atlantic Ocean from the United Kingdom southward to South Africa, including the North Sea and the Mediterranean Sea. It also occurs in the Indian Ocean, ranging from Kenya to South Africa. It occurs both close to the shore and further out, at depths down to about, but much of its time is spent in very shallow water at less than.

Ecology

The species largely feeds on crustaceans and bivalve molluscs that it excavates from the seabed. Other items in its diet include polychaete worms, gastropod molluscs, sea pens and small fish. Instead of having pointed teeth, it has flattened hexagonal bars and plates arranged in a mosaic pattern on its jaws; with these, it crushes the shells of its prey.
Reproduction is oviviviparous. A clutch of three to seven young develop inside the mother, receiving nourishment at first from their egg yolks, but later from fluids secreted by their mother into her uterus.

Status

The taxonomic position of this fish is unclear as populations in the Mediterranean Sea may be a different species from those in the southeastern Atlantic. In the Gulf of Lion in the northwestern Mediterranean Sea, populations declined in the 1970s, and there and elsewhere in the Mediterranean, the fish is under threat from intensive fishing. Along the coast of West Africa it is also the subject of artisanal fishing activities but these are less intensive and populations may be steady. The taxonomic uncertainty and the lack of data on populations of this fish has caused the International Union for Conservation of Nature to rate it as "data deficient".