A two and a half foot Alligator gar has been found on a canal footpath in South Wales. The dead fish was found by dog walker Caroline Brown, who said she had never seen anything like it before.
Native to southern North America, Alligator gars are huge predatory fresh and brackish water fish, attaining a maximum size of three metres, (10 feet!) and 137kg in weight. Despite their enormous size they were legally allowed to be sold for home aquariums until a few years ago, before their sale in England and Wales was banned by the Fish Health Inspectorate in the Import of Live Fish Act (ILFA, for short.)
Gars have been around since Jurassic times, are in the fossil record, and remain largely unchanged since then. The Alligator combines being highly predatory with huge size, tolerance of a wide range of temperatures and water types, toxic eggs, armoured scales and the ability to breathe air.
Prey includes fish, invertebrates, reptiles, amphibians, birds and mammals, and they are at the top of the food chain wherever they live.
But those super successful attributes also means that introduce them to non-native waters and they will cause havoc, eating a huge range of sometimes endemic fauna which aren’t evolved to be able to deal with them. They are a huge threat to native species, hence the ban. Let alone any diseases that they may introduce.
So is Garzilla going to be savaging the waterways of Wales anytime soon, and do you need to prevent dogs from swimming in the water? The answer is a resounding NO, or at least not in this century anyway.
Despite being classed as subtropical, no Alligator gar, Atractosteus spatula, or any of its relatives from the family Lepisosteidae will be surviving in British waters anytime soon, and sure as hell not in February when large parts of the UK experienced snow. It’s simply far too cold. So what was it doing there?
The fact that it was dead means that either the cold weather killed it, or it was dead anyway. But why was it on the path? Canals don’t flood as they are managed, although a river may have flooded into it, leaving the dead or dying gar high and dry when the water receded.
Or it was seen floating dead in the canal and someone hooked it out. Some prehistoric fish can travel overland like Polypterus, but the Alligator gar isn’t one of them, despite being able to breathe atmospheric air.
The fish may have died in someone’s home aquarium or tropical pond and the owner may have planted the fish there to cause trouble and drum up a bit of news. And it worked, by getting into the Sun newspaper. The RSPCA commented, but despite the amazing work they do with furry animals they aren’t fish people, so the fishkeeping community are better equipped to deal with the whys and hows, and maybe even the who.
Do you know anyone in South Wales who had a 30″ Alligator gar? You aren’t allowed to sell fish on Facebook anymore and shops won’t take Alligator gars because they get massive, and are banned, so maybe the owner thought they would release the fish to their local canal in some weird “it might be able to live there” scenario. Or they just plonked a dead Alligator gar on a footpath for fun.
Non-native predatory fish always make the news and usually it’s an (again dead) Piranha found in a British lake or river, and if that news coincides with a forthcoming Piranha movie, so much the better.
Alligator gars make the headlines for other reasons too these days. They are prized by sports anglers and monster fish hunters, who travel to the Mississippi and other waters in the hope of catching a record-breaking fish. They have also been featured on Jeremy Wade’s River Monsters and Zeb Hogan’s Monster Fish TV programmes, and even hunted by Bow fishermen, who like to hunt them by boat with bows and arrows attached to a rope.
Atractosteus spatula and all other gar species are still permitted to be kept in Scotland and Northern Ireland.
For more info on permitted species look here
Image by Greg Hume – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=30364231