Salamanders and Newts

As promised, our species comparison series returns to the world of herps. A few weeks ago we looked at turtles, tortoises, and terrapins, which are all reptiles. This week we’ll explore the differences between salamanders and newts, which are both amphibians.

Before going into the differences between salamanders and newts, let’s have a look at the differences between reptiles and amphibians. Both are cold blooded and can spend time on land or in water. Reptiles, however, spend more time on land generally. They breathe exclusively with lungs (some turtles are the exception, because nature hates following a hard rule). Amphibians spend more time in the water, generally, and can breathe air on the surface or below water, using their smooth, moist skin to exchange gases in many cases. Reptiles have dry, scaly skin that doesn’t breathe. Reptiles lay soft eggs on land, while amphibians prefer to lay their eggs in the water, usually in a gelatinous mass.

Rough-skinned newt

 Just as tortoises and terrapins are turtles but not all turtles are tortoises or terrapins, all newts are salamanders but not all salamanders are newts. Newts are a type of salamanders that prefer to spend most of their time living on land. Some lay eggs in the water, some on land. Some go through stages of development from larva to adult, some are just miniature versions of adults. Some salamanders have lungs, some have gills, some have both, and some have neither. There is much variety in the salamander’s order, so spotting the differences between salamanders and newts is difficult. A general rule is to look at the skin. Frog-like skin, which is smooth and wet, is a salamander. Toad-like skin, dry and warty, is a newt.

Northwestern salamander (USFWS)

A third critter thrown into the mix, also a member of the salamander order, is the siren. It looks and behaves like the salamander and newt, but instead of having four legs it only has two. Sirens have flat tails that they use for swimming, moving it from side to side like a fish does.

Greater siren (University of Georgia)

Are you confused by all this? Don’t worry about. I’m learning right along with you. Fortunately for you, all these technical terms and differences are merely to satisfy your curiosity; for me it’s a career choice. We’ll wrap up this series next week and leave the natural world for the labs and halls of scholarly debate. This week’s information comes from the SanDiego Zoo.

Mr. Frog and Mr. Toad

Part 4 of a continuing series on differences in similar critters brings us the frog and the toad. If you’re new to the show, or have a bad memory, you’ll recall that last year (and the previous two seasons) I was slogging through a pond looking for eggs belonging to frogs and toads (as well as newts and salamanders). They are out laying their eggs as we speak, so this week’s is a timely topic even if it has nothing to do with egg laying.

Frogs and toads are both amphibians, meaning they can breathe on land or in the water, and have similar body shapes. So how can you be sure which critter you’re looking at? Here are a few differences to help you figure it out.

Frogs are generally more aquatic than toads, although there is variation of aquaticness among both frogs and toads. Frogs have smoother skin, a taller and narrower body, and buggier eyes. When moving on land, frogs are magnificent jumpers. The hind legs are long and powerful.

Bullfrog with smooth skin and bugeyes

Cascades frog- note the long legs

Toads are famous for their warty skin, which will not give you warts. The body is wider and flatter than a frog’s. Toads don’t jump much; rather they walk or take small hops. The hind legs are shorter than a frog’s. Their eyes aren’t nearly as bulging as a frog’s. A frog is more likely to be near water, while a frog feels more comfortable straying from the water.

Western toad with bumpy skin and squat little body

Wyoming toad- note the shorter legs and less bulgy eyes
(USFWS)

If you ever encounter one of these critters in the wild, or even just your back yard, hopefully this helps identify what you’re looking at. Info this week comes from Kidzone. Next week we take a break from comparing similar species but the series will resume in April.

Amphibian Egg Mass Surveys

One of the things I do in my spare time (for self-serving fun and career development as well as stewarding my planet) is volunteer with Northwest Trek and Washington Department of Fish and Wildlife conducting amphibian egg mass surveys. No, I don’t go door to door asking questions about egg masses. I go to a pond and look for the eggs that several species of amphibians left behind following breeding.

            First, what is an amphibian? It’s a critter that leads a double life as both a terrestrial and aquatic animal. Unlike a reptile like an alligator that must surface to breathe, amphibians can breathe above or below water. The word amphibian comes from the Latin amphi bios meaning two lives.

            There are 27 species of amphibians in Washington, but WDFW only has us looking for the eggs of 8. They are Oregon spotted frog (state endangered, federally threatened), red-legged frog, American bullfrog (invasive to the Northwest), Pacific tree frog, western toad (candidate for listing as federally threatened or endangered), Northwestern salamander, long-toed salamander, and rough skinned newt.

            The pond I survey is in Eatonville. In and around, I have found eggs, tadpoles, or adults of four of those species. There were Northwestern salamander, Pacific tree frog, and red-legged frog egg masses; adult Pacific tree frogs, a red-legged frog, and American bullfrogs; and some tadpoles that were too fast to be able to identify.

American bullfrog

Red-legged frog

Pacific tree frogs

            To conduct a survey, I go into the pond with my partner Roger and slowly walk around looking for eggs. It seems like a challenge at first, but the egg masses are very obvious in most cases. Northwestern salamander egg masses are a huge solid ball of jelly, about the size of a grapefruit. They are likely to be attached to a pond lily stem. Pacific tree frog masses are smaller balls of jelly attached to smaller aquatic plants in most cases.

Northwestern salamander egg mass

Pacific tree frog egg mass

            When we find egg masses, we mark the location on a GPS and take a picture. It also gets logged on a tracking sheet. Last March the batteries in either the GPS or camera died and the spare batteries in our pack were also dead. It was a little frustrating switching batteries from one device to the other, especially because that was the day a river otter was helping us. It would’ve been great to get a shot of that little guy! As a consolation, we found a pile of his poo.

River otter scat

            Gently cleaning our waders before and after conducting a survey is a thoughtful way to help prevent the spread of invasives from one pond to another. It can also help reduce the spread of chytrid fungus, which causes disease in amphibians.

            The data we collect gets sent to the state to help biologists determine habitat conditions and species trends. Amphibians are an indicator species (species that can indicate trouble in an ecosystem by absence or presence) because their thin skin makes them very sensitive to environmental changes. By identifying trouble early on, biologists can analyze and correct the situation.

            Now you have a glimpse inside the working world of a nature guy. I’ll be back in the pond for a third season of egg mass surveying, starting this week. Weather permitting, of course. Don't forget to like Nature Minute on Facebook!