Salamanders

Alex Re

Hello, welcome to on wildlife. I'm your host, Alex Re. On this podcast, we bring the wild to you, we take you on a journey into the life of a different animal every week. And I guarantee you, you're gonna come out of here knowing more about your favorite animal than you did before. This episode is really exciting, because I'm sitting down with Mark manduca, the co founder and executive director of the amphibian foundation to talk about some amazing amphibians, salamanders.

Unknown Speaker

So salamanders are an extremely diverse group. There are over 600 different species, and you may look at them and think that they're just lizards. But lizards are actually reptiles, while salamanders are amphibians. Most amphibians spend part of their lives in the water and part of their lives on land. Some species such as the axolotl live exclusively in the water. Now, a large amount of salamanders are found in North America, but they can also be found in parts of Europe and Asia. And they like to hang out near the water and under rocks and other locations where it's kind of moist, and this is because of their skin. salamanders need to keep their skin moist so they can't really come out of hiding when the sun's beating down on them. This is one of the reasons why a lot of salamanders are actually nocturnal. The large number of salamander species means there's a whole lot of variety. For example, the largest salamander species is called the giant salamander, it can get up to four feet long and weigh around 60 pounds. While the smallest salamander, a species of pygmy salamander is only half an inch in length. salamanders are also carnivorous, meaning that they only eat meat. And they can eat all sorts of animals like worms, insects, and sometimes even fish depending on the species. tiger salamanders have even been known to be cannibalistic. They eat other individuals of the same species. And research shows that they're less likely to eat other salamanders if they grew up near their relatives. And scientists think that this might be due to the fact that they're taking other individuals that aren't related to them out of the population, meaning that they're reducing the amount of competition. They want all the offspring in the population to have similar genes to them. Speaking of offspring, most salamanders lay eggs, but they don't look like the eggs of snakes and lizards. First of all, they're laid in water, not on land. And second, they don't have a hard outer shell. They kind of look like clumps of clear jelly with black dots in the middle of them. And those black dots are the embryos, and females can lay a lot of eggs at a time. depending on the species they can lay over 200 eggs. Some salamanders lay their eggs in places called vernal pools. And these are temporary bodies of water that are caused by rain. And these vernal pools are really important because they're temporary, meaning that fish who like to eat salamander eggs can't live there. So you've probably noticed by now that salamanders are a little weird, but it gets weirder. Certain types of salamanders called ohms live in caves in complete darkness, and they have no pigment in their skin, and they're completely blind. The fact that they're blind may have to do with saving energy. They don't have to put any energy into trying to see in an environment where it's completely dark, so they can spend it on other things. But they do have some really cool abilities that make up for their lack of eyesight. They can sense the electricity that other animals give off underwater. And they can also sense changes in pressure that occur in the water. Needless to say, salamanders are really cool. But there's still so much to learn. We're going to take a short break. And when we get back, I'm sitting down with Mark manduca. Who's going to give us some more insights about these awesome animals. It's trivia time. What do you call mammals that lay eggs? A marsupials, B primates, C, endo thermes, or D monitoring? The answer is D monotremes. The platypus and the spiny ant eater are the only mammals that lay eggs. Hi, Mark. How are you doing today? Doing great. Happy to be here. Awesome. I really appreciate you coming on to tell us all about salamanders. All right, so let's get started.

Unknown Speaker

Yeah,

Unknown Speaker

so before we actually get into salamanders, can you just talk a little bit about yourself?

Mark Mandica

Absolutely, you know, I'm you know, I've focused most of my attention these days on amphibian conservation. When growing up, though, I never really saw any amphibians because I lived in suburban New Jersey, been about 150 years since there had been in Vivian's around there. So I don't know how I became like this. But, you know, it's my, my pleasure work with them today.

Unknown Speaker

That's great. And then you are a part of the amphibian foundation. So can you just talk about their mission? And what they what you do there?

Unknown Speaker

Yeah, absolutely. So my wife and I started the amphibian foundation just over four years ago, primarily because, you know, amphibians are declining very rapidly going extinct. And we felt like we we could do more, we felt like not enough was being done. You know, there's a lot of lot of work happening, a lot of great work happening, but these animals are still going extinct faster than we can stop it. So we wanted to devote our attention to it more directly.

Unknown Speaker

Yeah, absolutely. That's, that's, you're doing such important work right now. And so, earlier in the podcast, I talked about how salamanders are such a diverse group of organisms. And I just wanted to know, are there any interesting adaptations that are common across different salamander species?

Unknown Speaker

Yeah, yeah, absolutely, you know, in in salamanders are so fascinating to us. And we realize that, you know, even in the amphibian world, frogs get a lot of the attention and they deserve a lot of attention is just that people aren't really familiar with what a salamander is. So, we spend a lot of time getting the word out about salamanders. Because once you meet a salamander, you know, your hook. You know, one thing about them is that, at least here in the eastern United States, the majority of salamanders don't even have lungs, they they do all their breathing through their skin. You know, that's part of the reason why they're so susceptible to things that we've put into the environment because their skin is so vitally important. Everything is coming in and going out through their, through their skin there.

Unknown Speaker

Yeah, absolutely. And that's like one of the major differences you can tell between if it's like a lizard or a salamander, right, because lizards have very scaly, scaly, skin wall salamander skin is a lot more smooth, right?

Unknown Speaker

That's exactly right. And you know, a lot of people do confuse the two groups, lizards and salamanders. And because their body shape is very similar, you know, and that's mostly the reason for that is because the the ancestors to all of those animals had that same body shape. So it's just that lizards and salamanders have changed in that way, the least while the other groups have have really changed their appearance quite dramatically. So hopefully that makes sense.

Unknown Speaker

Yeah, absolutely. And kind of going off of that their skin, they have really cool coloration and patterns. And it seems like this would actually kind of make them stand out a little bit. Instead of blending in with their environment. Is there a reason that they have this coloration?

Unknown Speaker

Yeah, and actually, the reason is just what you said, the ones with that bright coloration are trying to stand out, you know, they're trying to be noticed. Those, those animals are typically more toxic than the ones that have more camouflage, ie colors, like browns, and greens and salamanders with bright colors are trying to stand out and get noticed as a warning to predators. Hey, you know, you might not want to push this. And interestingly enough, a lot of the salamanders with that bright coloration are also diurnal, you know, they're active during the day, where bright colors can be a more effective signal. And some of these animals with really bright coloration actually do hide at night. So where their colors might not convey that same message. Really, that's really interesting. And you'd never really even think about that. You just think, oh,

Unknown Speaker

that's got a really bright color, and not even second guess why they might have that.

Unknown Speaker

Yeah, there's a message in that bright coloration and that's interesting.

Unknown Speaker

Yeah. And speaking of sending messages and and communicating. How do salamanders communicate with each other? Do they make noises because I don't know if I've ever heard a salamander make any kind of noise?

Unknown Speaker

Yeah, they they don't make a lot of noise. I can't say they make no noise. But, you know, you associate frogs with noise like all of that. Not nocturnal choruses and singing and as much as sound and songs are important to frogs sent in chemical cues are important to salamanders. They, they do their communication through smell. It's very interesting and they have these crazy glands that mostly are more developed during the breeding season so they can better give off and detect these scent chemicals. But it's pretty fascinating and aquatic salamanders for example, you'll you'll see them using their tail to waft these scents towards the person they're trying to hurt the person the salamander is trying to communicate with pretty pretty cool stuff. You know a lot of smells a lot of scent communication with the salamanders

Unknown Speaker

absolutely and do you know like, what are these different sense? mean? Are they like mating sense or like territorial?

Unknown Speaker

They are mostly to me to my knowledge mostly like mating sense to them salamanders are extremely territorial. But as far as I know they convey that territoriality with biting and aggression. Much more direct, you know, then then a cent. But the, the salamander species have a choreography to their meeting that involves sent in this very predictable, choreographed breeding courting complex, that's all meant is to make sure that there, the male and the female are on the same page. They want to go ahead and do this. Pretty amazing in that way.

Unknown Speaker

That's, that's pretty crazy. Very interesting to me. So one of the most well known salamanders is probably the axolotl. And one of their defining characteristics is that they have some kind of like protrusions behind their head of what do you know what those are used for?

Unknown Speaker

Yeah, absolutely. And we can we can talk about this for a while. So just cut me off when you've heard enough but the the protrusions are gills. And actually all or almost all salamanders have those. It's just that most salamanders metamorphose. And then their gills are resorbed at metamorphosis, so you think of the gills as like salamander tadpoles. And again, almost every species has that but then they metamorphose and lose the gills and become terrestrial salamanders, whereas axilla models and some other really weird, fascinating salamanders never metamorphose. they retain those gills for their whole lives. So they look like tadpole salamanders for their for their whole life. And so that's a phenomenon known as paid amorphousness. It's an alternative to metamorphosis where the adults retain the juvenile characteristics. It's really, really weird. That is all. It's cool. It's cool, right? There's other things like mud, mud puppies, if you've ever heard of them, that's another group of salamanders that are the same as axolotl. They don't ever metamorphose so

Unknown Speaker

crazy. And because of that, they are mostly aquatic for their whole lives. wrecked, so

Unknown Speaker

Exactly. Whereas most salamanders are aquatic in the larval stage and then they metamorphose become terrestrial, but axolotl and mud puppies and some of the other pain amorphic salamanders stay aquatic, they keep the gills so they can live a chronically and they have fin folds on their tails that and you know, they're built for aquatic life.

Unknown Speaker

That's, that's really cool. And are they so I've also read that they can regenerate their limbs does that have to do with the fact that they stay in that larval stage or

Unknown Speaker

it doesn't. So that has been investigated really well in actual models, but also in another species of newt. And that can also regenerate. And you know, it's probably more common in salamanders, but it hasn't been studied. To my knowledge, let's see, I can think of other species that haven't been studied, but just anecdotally, I've seen them regenerate their limbs and tails too. And so it's just something that salamanders can do. It's very interesting for human researchers because we want to be able to do that and we can't so so it's been investigated a lot but an axolotl can lose its limit the shoulder and regrow the whole arm and a hand and fingers again. Wow. You know, so that's

Unknown Speaker

pretty amazing. Yeah, and I'm sure a lot of people are trying to recreate that in humans, but it's not gonna happen. Yeah, no, not anytime soon. So how are salamanders important to the ecosystems that they live in?

Unknown Speaker

Yeah, thank thank you for asking that question. And that is one I like to address a lot, because it's hard to get people excited about conserving these endangered amphibians when they don't understand the vital role that they play, you know, so first think about this. I'm here in the southeast, there is a tiny species, the red back salamander, it's the most common amphibian in metro Atlanta and in lots of other ecosystems as well. And it has more biomass than all of the birds and mammals combined. It's just that they're hiding. They're hidden. They're under stuff you don't know they're there. But not only are they there, but they account for more weight than all the mammals and birds combined. Wow. And so they're, they have a huge biological presence in these systems. And they're there and they're eating tons of bugs, you know, so think about, you know, on, some of them specialize in eating mosquitoes, but 1000 of them eat 5 million bugs every year. Okay, so that's crazy. They're out there doing a lot of work for us behind the scenes, without really us knowing much about them at all.

Unknown Speaker

That's, that's really vital to the ecosystem. And, and if you don't like bugs, you know, they should be thanking Salomon for that they

Unknown Speaker

should be thanking salamanders every day.

Unknown Speaker

Absolutely. And you said before, salamanders and other amphibians are especially susceptible to changes in their environment. Can you just talk a little bit about the challenges that they're facing right now?

Unknown Speaker

Oh, yeah, there's there are so many, you know, that that's part of the reason why 43% of the world's amphibians are documented is either in decline or already extinct. Okay. And from everywhere, you know, and part of it is their skin, you know, is one of the more vital organs that amphibians have, you know, you'll never see a frog drink. They're absorbing everything right through their skin. As we already mentioned, the salamanders are breathing through their skin, but amphibians in general to some degree of respiration right through their skin. But salamanders, some salamanders do 100% of it. So, you know, there's a lot and they're absorbing it in there for reacting. So there's compounds, chemicals, contaminants that we've put into the environment that's being absorbed into the amphibians, and they're responding. They've been responding since it's been being studied since the 80s. You know, they're below EPA level limits of, of agricultural chemicals that are, you know, that are deemed safe, you know, are causing these massive deformities and die offs in amphibians, and you know, it's a feminizing them is turning male, amphibians into female amphibians Really? Wow. So yeah, it's, it's a, it's a big problem. So and that's just, you know, that's just one you know, and then we have habitat loss. Obviously, that's a huge problem for amphibians. They're just losing habitat, very rapidly. Invasive species as a tremendous impact on amphibians, particularly cats, you know, people's cats, and now feral cats are outside killing hundreds of millions of amphibians. Every year, hundreds of millions, was just too many amphibians to be killed by, you know, an invasive species like a cat. And so, and actually, the list list goes on and on there, there are infectious diseases that are killing a lot of amphibians, and some of them are even killing, you know, these amphibians in pristine environments where there's very little development, there's, there's still still a lot of devastation there. So the story is pretty bleak. Could be because there are so many different documented causes of amphibian decline.

Unknown Speaker

Yeah. And obviously, their numbers are declining, and they're vital to the ecosystems that they live in. And yeah, this is going to be my last question, but is there anything that the average person can do that can help with the conservation of these animals?

Unknown Speaker

Oh, yeah, yeah, actually, we, we focus a lot on just answering that question, because, you know, we, we, I just told talk to you about a whole bunch of depressing stuff and it's important to To be able to direct people that are concerned, to what what you can do, you know, so we actually on our on our site, we have a lot of resources just for that. But off the top of your head, you know, of course, amphibian conservation groups like ours and others are always in need of funding. So I gotta say that, you know, if you want to contribute directly, we have a membership program as well. But there's a lot of stuff that you can do in your neighborhood, you know, it doesn't have to be on a global scale or a country scale, you know, there's things you can do to make your yard more amphibian friendly, we have resources for that off of our website as well. And a direct link to our blog, which I'll just say it's backyard dot frogs need our help.org. That link will take you directly to a resource of a growing list of resources that I've been putting together probably for 10 years about ways to make your yard more amphibian friendly, and things you can do to do to encourage amphibians, because if you're encouraging amphibians, you're also encouraging other wildlife to. And so it's a resource for that. There's lots of community science programs too, like frog watch, if you want to spend, you know, an hour a month, monitoring amphibians in your area and contributing that data to a larger program. Look up frog watch, but again, on our main website, amphibian foundation.org. We go through a list of those ways that you can get further involved.

Unknown Speaker

That's, that's really great. And I personally would love to have a bunch of amphibians in my backyard.

Unknown Speaker

Yeah. It's great. You know, and we live in in Atlanta. So we don't actually have that much amphibian bio going on in our yard. But we we encourage what we can for sure,

Unknown Speaker

yeah, absolutely. Well, Mark, thank you so much for coming on the podcast, you brought us some amazing and important insights into the lives of salamanders. So thank you. It's my pleasure. All right. Thank you very much for inviting me. That was such an amazing interview. And I think we all learned how important salamanders are to the structure of our ecosystem. We can all do our part to help these animals. And that starts by supporting organizations like the amphibian foundation that are working towards their conservation to other organizations that you should definitely check out after looking at the amphibian foundation or save the salamanders and foundation for the conservation of salamanders. Thank you so much for coming on this adventure with me as we explored the world of salamanders. You can find the sources that we used for this podcast and links to organizations that we reference@www.on wildlife.org and that's on wildlife.

Jess Avellino

You've been listening to on wildlife with Alex Re brought to you every Wednesday.

Transcribed by https://otter.ai