Stingray
Stingrays are very common and are to be found in tropical waters all over the world. They are a family of flatfish, or more particularly, rays, whose relatives include both sharks and skate.
They generally live in coastal waters, although there are quite a few different types of stingray living in fresh water in Asia and Africa, as well as in North and South America.
Wings, rather than fins, with which they ‘fly’ through the water, gracefully, in a gyrating movement, enable them to trawl the seabed for the molluscs, crustaceans and small fish; their invariable diet. Eyes on top of the heads of any one of the 70 or so different types of stingray are similarly placed, but they are the primary predator attack warning indicators, rather than having food-seeking capability, which relies on other attributes.
Stingrays have long whip-like tails, at the end of which is a serrated, sharp or barbed growth like
a fingernail which contains poison or venom. This can be over one foot (34 cms) long. On the underneath of the spine are two grooves which contain the venom, the whole tail being sheathed in a layer of skin which contains the venom.Stingrays vary in size from saucer or hand size to around 6 feet (2 metres) in diameter, the larger ones having tails over 6 feet long including the barb. Total lengths of some rays often exceed 14 feet (4 metres).
Stingrays bare their young in litters of five to ten and being viviparous these are born alive.
Stingrays have eyes on the top of their head and so cannot see their prey. As bottom feeders they use electro-receptors and smell, rather the same as sharks, to find their food which usually consists of molluscs and crustaceans with occasionally small fish.
Stingrays are fairly placid creatures and will avoid danger rather than have to actively defend themselves. Their only real predators are sharks, other than these they are, perhaps not surprisingly, normally left alone by other fish.
Very occasionally humans come too close to them and their automatic defences allow their tail to attack, as by a whip, causing a lot of pain for an hour or so, a nasty cut and two or so more day’s trauma. This is usually the result of being trodden on so the automatic reaction to whip the tail tends to ‘hit’ the foot or leg of the human.
Stingray stings are very rarely fatal. Recent publicity concerning the unfortunate death of Australian wildlife expert, the popular and ebullient character Steve Irwin shows that he was in the wrong place at the wrong time to have been hit directly in the heart, a million to one chance. Indeed only around 20 deaths from stingray stings have been recorded this century.
Stingrays are often caught by mistake by fishermen, particularly if they are using crab as bait, and some are sought by spear fishermen. The smaller stingrays taste better than the larger ones, the area of flesh around the eyes and the liver being favoured, as much of the remainder is somewhat rubbery. They are not looked at as ‘commercial’ fish, although you will find them in most fish markets in tropical waters.
By: Cindy Sekela
Article Source: http://animalarticles.com
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