I came across these guys while browsing the wonderful world of the internet for strange animals. Really big animals always seem to catch my eye, so the name giant salamander leaped out at me. These fellows have the distinction of being the world’s largest (and probably ugliest) amphibians. There are only three species in this family, the hellbender in North America (which only grows to a piddling 2 feet), and the Chinese and Japanese giant salamanders, which are the true behemoths of the family.

Japanese salamanders are the slightly smaller of the two, only growing to 4.7 feet. The Chinese salamander, on the other hand, can grow up to 5.9 feet. That is one massive salamander. As I mentioned, giant salamanders are not the beauty queens of the animal world; they have wrinkled grey, black and green skin, making them look really unpleasant.

A giant salamander in a zoo. Image By Petr Hamerník – Zoo Praha, CC BY-SA 4.0

These salamanders to not undergo complete metamorphosis, so they still have gill slits, and also have lungs (in a normal salamander the gills would be lost in favour of lungs as the young change into adults). However, the gill slits are closed, and the lungs do not perform any gas exchange. Instead of using either of these highly developed structures that other animals have found so successful, the giant salamander opts for a simpler process, simply having gases diffuse in and out of the skin. The many folds in the salamander’s skin increase surface contact with water, allowing for more efficient gas exchange.

Since they need to be in it to breath, giant salamanders tend to spend most of their lives in water. They prefer cold mountain streams, where the water is swift enough to provide enough fresh oxygen for the salamanders. They are nocturnal, only leaving the shelter of stream rocks at night. They are very territorial, and large males will often kill smaller males to protect their space.

Giant salamanders eat pretty much any meat they can find. They open their huge mouths which creates negative pressure in the mouth and sucks prey in. Because they have tiny eyes that really don’t see much of anything, and because they hunt in the dark, giant salamanders use smell and touch to find their prey. They have special nodes on their heads that can sense small differences in water pressure that might be caused by prey.

Giant salamanders mate in special ‘spawning pools’ which males aggressively defend and return to every year. A female will approach the spawning pool and lays her eggs, then hits the road. The male, on the other hand, fertilizes the eggs and watch over them carefully, chasing away potential predators like fish or other salamanders. Though this seems like good parenting, it may be motivated by the male’s desire to protect his spawning spot and not necessarily the eggs. Still, he gets the job done, and that’s the important thing.

While Japanese giant salamanders are not particularly threatened by extinction, Chinese salamanders are critically endangered. This is mainly due to habitat loss and over-harvesting for food. Stairways are now built into dams to allow the species to travel to breeding grounds. Hopefully with further conservation methods we can preserve this wonderfully odd and ugly species.

Cover image By Shu Chen Andrew A. Cunningham Gang Wei Jian Yang Zhiqiang Liang Jie Wang Minyao Wu Fang Yan Hanbin Xiao Xavier A. Harrison Nathalie Pettorelli Samuel T. Turvey – https://onlinelibrary.wiley.com/doi/full/10.1002/ece3.3862, CC BY-SA 4.0