Episode 104: Tiger Salamanders

Published: Jan. 28, 2019, 7 a.m.

Thanks to Connor who suggested this week\u2019s topic, tiger salamanders! Not only do we learn all about the Eastern tiger salamander and the banded tiger salamander, we also learn where asbestos comes from AND IT\u2019S NOT EVEN LIKE I GOT OFF TOPIC, I SWEAR\n\nThe Eastern tiger salamander:\n\n\n\nThe barred tiger salamander:\n\n\n\nA baby tiger salamander:\n\n\n\nA CANNIBAL BABY TIGER SALAMANDER:\n\n\n\nShow transcript:\n\nWelcome to Strange Animals Podcast. I\u2019m your host, Kate Shaw.\n\nThis week we\u2019ll learn about an animal suggested by listener Connor that\u2019s been waiting on the ideas list for way too long. Thanks, Connor! Sorry it took me so long to get to your suggestion!\n\nSo, Connor suggested that we cover\xa0\u201ctiger salamanders\u2019 cannibalism and how salamanders were once believed to be fire-related.\u201d That sentence gives us a lot to unpack.\n\nFirst let\u2019s find out what a tiger salamander is. It gets its name because it\u2019s stripey, or at least has blotches that can look sort of like stripes. It may be yellow and black or green and black. It grows up to 14 inches long, or 36 cm, which is pretty darn big for a salamander. Smaller tiger salamanders mostly eat insects and worms, but the bigger ones will naturally eat bigger prey, including frogs.\n\nLike all salamanders, the tiger salamander is an amphibian. That means it\u2019s cold-blooded with a low metabolic rate, with delicate skin that needs to stay damp. Like other salamanders, it doesn\u2019t have claws, it does have a tail, and its body is long compared to its short legs. Basically a salamander usually looks like a wet lizard. But salamanders actually have more in common with frogs than with lizards, since frogs are also amphibians.\n\nWhile the tiger salamander can swim just fine, it spends most of its adult life on land. It catches insects by shooting its sticky tongue at them just like frogs do. And just like a frog, the tiger salamander\u2019s eyes protrude like bumps on its head, and it retracts its eyeballs when it swallows to help force the food down its throat. This is fascinating, but you might want to take a moment to be glad you don\u2019t have to do this every time you swallow a bite of food.\n\nThe tiger salamander, like most other amphibians, secretes mucus that helps its skin stay moist and tastes nasty to predators. The tiger salamander doesn\u2019t appear to actually be toxic, though. It mostly lives in burrows it digs near water, and while it\u2019s common throughout much of eastern North America, it\u2019s not seen very often because it\u2019s shy and because it prefers ponds in higher elevations such as mountains.\n\nA female lays her eggs on the leaves of water plants in ponds or other standing water. The eggs hatch into larvae which have external gills and a fin that runs down its back and tail to help it swim. At first the larva looks a little bit like a tadpole, but it grows legs soon after hatching. As a larva, it eats aquatic insects and tiny freshwater crustaceans like amphipods. How soon it metamorphoses into an adult salamander depends on where it lives. Tiger salamanders that live in more northerly areas where summer is short will metamorphose quickly. Tiger salamanders that live in warmer climates stay larvae longer. And in areas where the water is better suited to gathering food than the land is, the larvae may not fully metamorphose at all and will live in the water their whole lives. The term for a fully adult salamander that still retains its external gills and lives in the water is neotene, and it\u2019s pretty common in salamanders of various species.\n\nThe tiger salamander is actually closely related to the axolotl, more properly pronounced ash-alotl. I learned that from the Varmints! podcast. Most axolotls are neotenic. On the rare occasion that an axolotl metamorphoses into its adult form, it actually looks a lot like a tiger salamander.\n\nUnfortunately, the tiger salamander carries diseases that can kill frogs, reptiles, fish, and even other amphibians,