Environmental Engineering Reference
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area,withboatslaunchingmainlyfromBurryPort,SwanseaandOxwichBay.Anumberofanglingboats
also operate commercially under charter, catching species such as the tub gurnard Trigla lucerna (Fig.
65). This is the largest of the gurnards found around Gower, reaching a maximum length of 0.75 metres,
although most individuals are between 0.5 and 0.6 metres. Like all gurnards it has a large head covered
by protective bony plates, and the lower three rays of the pectoral fin are separate and fleshy. It is usu-
ally found on mud or sandy seabeds, feeding on small fish such as sand eels, gobies and dragonets Cal-
lionymus lyra , and on crabs and shrimps. They will also feed high in the water when there are plenty of
small fish about and can sometimes be seen breaking the surface. The Welsh record rod-caught tub gurn-
ard was caught from the shore at Langland Bay and weighed nearly 5 kilograms. Potting for lobsters,
edible crabs and velvet swimming crabs takes place in the rocky areas inshore while offshore there is
trawling for plaice, sole, whiting Merlangius merlangus and cod Gadus morhua . Tangle nets are used to
catch rays and turbot Psetta maxima . Netting for bass takes place with both fixed and drift netting and
there is bottom-set netting in winter using small-mesh nets to catch sole, whiting and cod.
In 2004 a sea sturgeon Acipenser sturio weighing 120 kilograms and nearly 3 metres long was caught
inSwanseaBay.OneofthelargestEuropeanfishtobreedinrivers,theseasturgeonhasbeenfishedtothe
brink of extinction and is now a protected species. It should not have been killed and it seems that more
information needs to be provided to fishermen about rare species. The elongated body tapers to a narrow
pointed tip at the snout and lacks scales, apart from the five rows of whitish bony platelets, or scutes,
that run the length of the fish. Sturgeons have no teeth, but feed opportunistically on bottom-dwelling
creatures, feeling for prey amongst the mud with the sensitive barbels on the chin and then sucking them
into the mouth. Their food consists mainly of invertebrates and small fish. Previously abundant along
all European coasts, sturgeon are now restricted to a single population that breeds in the Gironde River
in France and the species is consequently extremely vulnerable. These long-lived and slow-growing fish
have been extensively fished both for their flesh and for the eggs, which are sold as caviar. A captive
breeding programme is currently in progress with the long-term goal of reintroducing the fish to some of
its former range. After some controversy about its sale by the fisherman who caught it, the sturgeon was
senttotheNaturalHistoryMuseum.Thefishwasprobablymorethan100yearsoldanditwilleventually
be held as part of the national fish collection.
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