Episode 261: Walking Fish

Published: Jan. 31, 2022, 7 a.m.

b'Sign up for our mailing list! We also have t-shirts and mugs with our logo!\\n\\nThanks to my brother Richard for suggesting one of the fish we talk about this week--fish that can walk! (Sort of.)\\n\\nFurther watching:\\n\\nVideo of a gurnard walking\\n\\nFurther reading:\\n\\nWalking shark moves with ping-pong paddle fins\\n\\nWalking sharks discovered in the tropics\\n\\nThe Hawaiian seamoth (the yellowy one is a larval seamoth, the brighter one with the snoot the same fish as a juvenile, both pictures by Frank Baensch from this site):\\n\\n\\n\\n\\n\\n\\xa0\\n\\nThe slender seamoth (an adult, photo from this site):\\n\\n\\n\\nA flying gurnard with its "wings" extended:\\n\\n\\n\\nA flying gurnard with its "wings" folded, standing on its walking rays:\\n\\n\\n\\nAn eastern spiny gurnard standing on its walking rays:\\n\\n\\n\\nA mudskipper\'s frog-like face:\\n\\n\\n\\nMudskippers on land:\\n\\n \\n\\nWalking sharks:\\n\\n \\n\\nShow transcript:\\n\\nWelcome to Strange Animals Podcast. I\'m your host, Kate Shaw.\\n\\nThis week we\\u2019re going to look at some weird fish, specifically fish that use their fins to walk. Well, sort of walk. Thanks to my brother Richard for suggesting one of these fish.\\n\\nBefore we get started, let\\u2019s learn the terms for a fish\\u2019s two main pairs of fins. Different types of fish have different numbers and locations of fins, of course, but in this episode we\\u2019re focusing on the pectoral fins and the pelvic fins. Pectoral fins are the main fins in most fish, the ones near the front on each side. If a fish had arms, that\\u2019s roughly where its arms would be. The pelvic fins are near the tail on either side, roughly where its legs would be if fish had legs. If you remember that\\xa0people lift weights with their arms to develop their pectoral muscles in the chest, you can remember where pectoral fins are, and if you remember that Elvis Presley was sometimes called Elvis the Pelvis because he danced by shaking his hips, you can remember where the pelvic fins are.\\n\\nSo, let\\u2019s start with the seamoth, which lives in shallow tropical waters of the Indo-Pacific Ocean and the Red Sea, including around Australia. We don\\u2019t know enough about it to know if it\\u2019s endangered or not, but since it\\u2019s considered a medicine in some parts of Asia, it\\u2019s caught to sell as an aquarium fish, and its habitat is increasingly impacted by bottom trawling and coastal development, it probably isn\\u2019t doing great. It\\u2019s never been especially common and doesn\\u2019t reproduce very quickly. Researchers think it may even be a social fish that forms a pair bond with its mate, since pairs are often found together.\\n\\nThe seamoth doesn\\u2019t even look that much like a fish at first glance. It\\u2019s covered with bony plates that act as armor, including bony rings around its tail. It even has to shed its skin as it grows larger.\\n\\nThe seamoth has a long, pointed snout with a tiny mouth underneath, but it can protrude its mouth out of its\\u2026mouth--okay that doesn\\u2019t make sense. Basically it\\u2019s able to extend its mouth into a tube that it uses like a straw to slurp up worms and other small animals from the sea floor.\\n\\nIt can change colors to match its surroundings too. If all this makes you think of seahorses and pipefish, the seamoth is related to both, but it looks very different because of its fins.\\n\\nThe seamoth\\u2019s pectoral fins are so large they resemble wings, and its modified pelvic fins are stiff and more fingerlike than fin-like so that it can walk across the sea floor with them. It spends most of its time walking on the sea floor, only swimming when it feels threatened and has to move faster. Sometimes a seamoth will cover itself with sand to hide from a predator. During breeding season, males develop brightly colored patterns on their pectoral fins.\\n\\nThe seamoth is a small fish, with the largest species growing about five inches long, or 13 cm. One species of seamoth, the little dragonfish, sheds its armor in one big piece\\u2014not just once or twice a year, but as often as every five days or so when it needs to rid i...'