Walking fish By Gyan, Yr 7 Mentor‐ Miss Firth What fish can walk/live out of the water and which one is the best walking fish overall? Introduction: A Walking fish is a fish that can walk on land, using its special abilities. It’s a very evolved fish. They make/ find their homes on land and live there until they need to go back in the water for oxygen again. I will now show you four types of Walking fish and some facts about each one. I will then say which one I think is the best Walking fish out of the four. Mudskippers – (Oxudercinae) A mudskipper is a fish with two big eyes on both sides of its head. A mudskipper is a type of walking fish which can walk on land. In fact, the mudskipper can survive up to a large number of days on land; in fact they spend most of their time on land. Although it would then need to look, with its two bulging eyes, out for its predators: the monitor lizard, crocodiles and many more creatures, who love to snack on mudskippers. As you would be able to tell from the mudskippers’ name, the mudskippers live on/in mud and they also eat their mud for food, although, if another mudskipper comes onto the other mudskipper’s mud it will show a sign that it will fight with the other mudskipper if it comes too close to their mud by raising its fin but if the other mudskipper doesn’t listen to the mudskipper, they will definitely fight over their space of mud. A mudskipper needs water to survive, so they wouldn’t be able to get water when being on land so much, however, they can! A mudskipper survives by storing water in their large gill chambers; they need water when in the air, the exact opposite way to when humans need air when in the water. Mudskippers can swim… but they can’t swim in deep water as they aren’t great swimmers, so they stay in the shallower part of the water so they can swim easily. They collect oxygen, by using their blood vessels, from the water which then absorbs into their bloodstream. I think that the mudskipper is a great type of walking fish as it’s well known; they are very protective of their homes, which is a good thing. They can stay on land, like their patch of precious mud, for many days; however, the mudskipper isn’t so great because it has many predators like: the monitor lizard, crocodiles and more. Walking Catfish – (Clarias batrachus) “The walking catfish has another organ that supports its gills and helps it take in oxygen from the air.” The walking catfish needs to breathe on land and it has its special way of how to; it has another organ in its body which helps its gills to collect oxygen from the air whilst on land. “After a big rainstorm, it’s not unusual to see catfish wiggle across the road," says George Burgess, an ichthyologist at the Florida Museum of Natural History. They live in places “such as muddy ponds, canals, ditches, swamps and flooded prairies.” The countries that they live in are: “Pakistan, eastern India, Sri Lanka (Ceylon), Bangladesh, Myanmar, Thailand, Malaysia, Singapore, Indonesia, and the Philippines.” They have many predators, such as: other fish, “reptiles, birds, and mammals. Wading birds are particularly adept at exploiting walking catfishes "stranded" in shallow pools and other evaporating water bodies.” Sadly, sometimes, walking catfish will be walking on land as usual, (motorways, roads...) however, sometimes they can get run over by oncoming traffic, so cars could be one of their predators too! On the one hand, the Walking Catfish is a great walking fish as it has its own special organ to breathe on land, plus another thing that makes it great is that they are very highly populated across many different countries across the whole of Asia. On the other hand, the Walking Catfish is not an amazing fish because they have so many predators, for example, other types of fish, reptiles and many more. Killifish – Mummichog – (Fundulus heteroclitus) The Mummichog is part of the Killifish family. The Mummichogs home is “along sheltered shores where the tide flows over beds of eelgrass or salt hay”. Mummichogs grow from 3½ inches to 6 inches long. Mummichogs also feed “on insects, larvae, small fish and crustaceans, and plant material at the water’s surface.” They have also been known to live in the Gulf of Maine. Habitats for mummichogs are: saltwater marshes, estuaries and in sheltered shores where tides flow over eelgrass. The common feature between these habitats is that there’s submerged vegetation where the fish can spawn and feed.” Mummichogs can survive for over one hour in water up to 34Ԩ, which is a temperature that most fish wouldn’t be able to survive in for a few seconds. “The Mummichog is stout‐bodied with a flattened head, rounded or squared‐off tailfin, pointed teeth and a lower lip that juts out beyond the upper one. Female mummichogs are larger than males. Coloration varies with their gender and shading can change based on surroundings. Females have a brownish green body featuring 12‐15 dusky vertical stripes, with green tinted dorsal and anal fins. Males are darker than females, with a green or olive body featuring 15 silver vertical stripes. Males have yellow pectoral, pelvic and anal fins and have blue or orange markings present during spawning season.” The Mummichogs’ predators are: large predatory fish and birds, humans are also one of its predators. I think that Mummichogs are great fish because they have a great place to live, along shores which have a shelter for them, they are well known and they don’t have too many predators, just a few. West African Lungfish – (Protopterus annectens) West African Lungfish are freshwater fish. They can survive in temperatures from 25°C to 30°C. Its maximum length is 100cm and its maximum weight is 4kg. Its body has 34 to 37 ribs and its tail fin is short. The West African lungfish are found in “the large Sahelian basins, Comoé River, Bandama River and some basins of Sierra Leone and Guinea, including: Senegal, Niger, Gambia, Volta and Chad basins, with also the temporary tributaries of Chari River in western Sudan.” They are found in these places, in the weedy areas of swamps and backwaters of rivers and lakes. “It normally lives on flood plains and when these dry up, during the dry season, it secretes a thin slime around itself which dries into a fragile cocoon; it can exist in this state for over a year, although normally it hibernates only from the end of one wet season to the start of the next. For hibernating the fish literally chews its way into the substrate ejecting mud out of its gills; it may reach a depth of 3‐25 cm below the bottom depending on the length of the fish; the lungfish wriggles around, thereby hollowing out a bulb‐ shaped chamber and then resting with its nose pointing upward; they breathe air at the mouth of the chamber's tube and then sink back into the expanded part of the chamber. As the water disappears the respiratory trips cease; air reaches the fish via the tube to the surface. Also under aquatic conditions this lungfish can survive more than three and half years of starvation; it shows the same behaviour ‐ no motion. Carnivorous, its food includes molluscs but also frogs” and more, it can also feeds on plants. The lungfish spawn in the wet season; the white eggs are cared for by the males. The eggs hatch in eight days and have then left the nest in twenty days. Its predators are bony fish like the finfish. The West African Lungfish is a very good fish as it has a great place to live, it has a great place to spawn and protect their eggs, they’re widely dispersed across western Africa, it’s a well‐known fish and it doesn’t have too many predators. Conclusion Overall, I think that the best type of walking fish is the Mudskipper because in my opinion compared to the other fish it has the best home and they’re protective of it, the Lungfish has a good home but they aren’t very protective of it so any predator could come to it and there’d be no defence there for its home. The Mudskippers seem to have the least amount of predators. Also, they can survive for many days on land while storing water in their gill chambers, the Lungfish can survive years without water in their cocoon however, they aren’t awake while without water. I also think they are the fish that would survive the longest out in the wild. Other examples of walking fish are: Four‐eyed fish Snakehead Grunion Link: http://news.nationalgeographic.com/2015/12/151205‐animals‐science‐fish‐walking‐water‐ oceans/?utm_source=Facebook&utm_medium=Social&utm_content=link_fb20151205news‐ animalqfish&utm_campaign=Content&sf16574522=1 Music: https://www.youtube.com/watch?v=Y29RZpHnkq8 .