An endangered swordfish has been found dead on a beach in South Wales.
The 224cm long billfish was found yesterday on Barry Island beach, near the Vale of Glamorgan in South Wales, and is believed to weigh 60-80 kg.
The identity of the fish was confirmed by Doug Herdson, Information Officer for the National Marine Aquarium in Plymouth, who manages the UK Marine Fish Recording Scheme.
Herdson said the fish was a swordfish, Xiphias gladius, the sole member of the swordfish family Xiphiidae:
"The records show that while swordfish are rare, they do turn up from time to time in the waters around the British Isles; but there have only ever been three marlins found in the UK.
"The first swordfish in Wales was off Newport back in 1905; while in 2003 one was stranded at Rhossili on the Gower, despite efforts to rescue it , it died an hour later.
Swordfish, Xiphias gladius. Picture by the National Museum of Wales.
"They are found throughout the tropical and temperate waters of the world but appear to prefer sea temperatures of 18C to 22C, migrating to cooler waters to feed in the summer.
"These oceanic fish chase herring and mackerel and are among the fastest fish reaching 90 kph/56 mph. This is in part due to their being warm-blooded, which allows not only their muscles but also their brain and eyes to work more efficiently."
The swordfish had been dead for only a few days and had been scavenged by other creatures, so it was not possible to determine the cause of death.
The fish is now with the National Museum of Wales, where it is due to enter the national collection.
The species can reach a maximum size of 455cm and can weigh up to 650kg/1400 lb. The world record for a specimen caught on a rod and line was a 536kg/1182 lb fish caught off Chile in 1953.
Swordfish, Xiphias gladius. Picture by Colin Smith.
Under threatOverfishing has placed the swordfish under serious threat. In 1998 a study showed that the swordfish population of the North Atlantic had dropped to 35% of its original size.
Part of the reason for the demise of the species is the length of time it takes for the fish to reach sexual maturity.
Although females can produce 30 million eggs a year, which might allow them to recover rapidly from depletion, they don't reach sexual maturity until they're around 70kg.
However, the average size at which the species is caught by fishermen is around 40kg, so the majority of fish are being eaten before they have a chance to reproduce.
The National Marine Aquarium said that although drastic fisheries control measures for swordfish had been introduced in the North West Atlantic there was some debate as to how effective they were, as some claimed that stocks were only at half the level of a sustainable population.
The Aquarium said: "Unfortunately, with stocks at these levels swordfish steak must now be on the fish to avoid list. It is to be hoped that effective fisheries management can be enforced in both the West and the East North Atlantic so that we can once again enjoy this delightful fish, both in the wild and on the plate."
The UK Marine Fish Recording Scheme welcomes reports of unusual marine or estuarine fish spotted around the UK. To make a report you can contact them on 01752 275 216 or email [email protected]