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Our Local Shrimp
Of the 350 known species of mantis shrimps only two are found in British waters. One of these, Rissoides desmaresti, is a southern European species that is common in the Mediterranean. It is has been found at several locations in the English Channel, southern North Sea and in North Wales, yet the population in the Solent has been known for over 150 years and appears to be increasing. Most recent information has come from oyster fishermen, who catch them while dredging during the winter months, but they have also been caught in nets, pots and found in rock pools. The species is included within the Isle of Wight Biodiversity Action Plan (BAP), as the area appears to hold important populations. The Project The project has two main objectives:
Project Partners: Medina Valley Centre More on Mantis Shrimps Mantis shrimps are aggressive marine crustaceans known as Stomatopods (which means ‘mouth foot’). Most known species live in shallow waters of tropical and subtropical seas. They feed on a variety of marine animals including worms, snails, shrimps, crabs and fish. They are seldom seen because of their retiring habit of living in burrows in the sea bed or in rock cavities. From their secretive hide-out, they ambush their unwary prey by sudden high-speed strikes of their large raptorial limbs – rather like a praying mantis – but several times faster! (approx 1 metre per second). They are divided in to two groups – the spearers and smashers. The spearers, like the Solent species, stab their prey with forelimbs that are equipped with sharp spines. The forelimbs of the smashers have a ‘blunt heel’ – equivalent to a boxing glove – and normally feed on armoured animals such as clams and crabs. The strike of a smasher has a force approaching that of a small-calibre bullet; a large specimen from southern California broke an aquarium wall consisting of a double layer of safety glass! Even small species (80mm) can break the wall of an ordinary glass aquarium. Colour is important to mantis shrimps. They possess one of the most complex visual systems in the animal kingdom. Many species live in diverse tropical coral reef habitats and have coloured markings which are used in communication between and within species. They appear to perceive stunningly complex colour vision. They have eight or more primary channels (we have just 3 - Red, Blue and Green) plus polarisation vision (we need to wear sunglasses to reduce the glare). They are even able to detect UV light – a part of the spectrum we are blind to. Each eye is also able to move independently and can judge distances. Find out more about Mantis Shrimps on: www.blueboard.com/mantis If you find a mantis shrimp – don’t touch it – in case it grabs you! Please contact us with the following details. Even if you have seen one in the past then this is also of interest. Please record: Download the poster - NB it is A4 and 470kb
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