An Awakening Of Amphibians

by Mary Richmond

If you’re feeling weary of the dreary-not-exactly-spring weather we’ve been having, I’ve got some little miracles for you to check out. They’re so subtle and common that many of us overlook them as we search for bigger, maybe splashier things.

Look no farther than the amphibians if you want to see and hear little miracles, though. These small, often slimy animals inhabit an incredibly large part of our biome. But I rarely see one, some of you may say, and that’s probably true, but I bet you caught tadpoles, often called polliwogs, when you were young. Perhaps you have a garden toad or frogs in your garden pond. If you look under logs in the woods or even dig around in a little moss you may find a salamander or two.

By definition, an amphibian is an animal that lives part of its life in water and part of it on land. They are vertebrates and are cold-blooded. All lay eggs outside their body and fertilization takes place in the water in most cases, not by traditional mating. Ninety percent of amphibians are frogs. The frog family includes all toads.

Amphibians can breathe through their skin, both in the water and out of water. This means their skin must remain moist at all times. Most live near water or close to it, though some live in very wet forests, even in the canopies of rain forests. Because of their thin skin that allows oxygen to flow in and out, they are also susceptible to absorbing toxins. All over the world amphibians are showing signs of environmental stress which is very concerning to the scientists and medical professionals who study them.

Because they are cold-blooded, amphibians cannot survive temperatures below 50 degrees Fahrenheit for extended periods. In the fall they bury deep into the earth or under the mud in ponds where they live in a suspended state of dormancy that is similar to hibernation. Once the air warms consistently to 50 in the spring they begin to emerge.

Often the first time most people think about amphibians is when they hear the spring peepers begin to chorus on damp March nights. These small frogs are only about an inch long, but they have a commanding voice, as anyone who lives near a swamp can confirm.

March is when the vernal pools, small bodies of water that are impermanent and often dry up in the summer, become very active. Several obligate species are easily found in Cape vernal pools even now, including the large yellow spotted salamanders and the wood frogs that quack like ducks.

On rainy, warm nights in March the spotted salamanders, which usually spend most of their time underground eating worms, grubs, and other squishy delectables, awaken and plod through the mud and rain to their ancestral vernal pool. If you are lucky enough to witness this spectacle you will see hundreds of salamanders gathering in the shallow water where they will swarm to both lay and fertilize thousands, even millions, of gelatinous eggs. When the orgy is done the exhausted salamanders will leave the pool and return to their humble, quiet lives in the mossy muck of the forests and swamps, invisible to most passersby for another year.

Wood frogs can also be seen gathering in vernal pools. They can be spotted during the day but are especially active at night. Listen for their low croaks that sound a lot like the quacks of ducks. You must be quiet and sneaky to catch a glimpse of them, but it’s worth the effort. You will see dozens of male frogs floating on the water, their little throats extended as they call for female attention. Any movement by any frog, male or female, will cause a mad dash across the water’s surface. No one wants to lose an opportunity to fertilize eggs!

All of our local frogs and toads lay eggs in fresh water in the spring. Some tadpoles develop legs and leave the water quickly but others, like the large bullfrogs, may spend several years in the water. Those that develop quickly leave the water when very small and immediately hurry to damp leaf litter or mossy areas where they will be able to hide from danger. These small amphibians provide food for all sorts of birds and animals, and by the end of the summer only a small percentage of the masses of eggs laid and fertilized will reach adulthood and be able to reproduce.

Amphibians may not be on everyone’s favorite animal list, but maybe they should be. Tadpoles eat algae and detritus but also small larvae of mosquitoes and other insects, water worms, and other minute pond creatures. Adult frogs eat all sorts of insects and worms as do the toads that visit our gardens.

A healthy population of amphibians bodes well for our environment, so it is in our best interest to not be adding fertilizers and poisons to our lawns and gardens that seep into our water supply, ponds, rivers, and estuaries. If frogs are growing massive tumors, extra limbs, and other abnormalities as a result of toxins in the environment, what does that mean for the future of all of us?

We have many frogs and toads here on the Cape as we have many freshwater areas. If you’d like to learn their different calls, check out some of the online resources that have recordings.

We love to think about miracles but often we are looking for big things when there are little miracles around us all the time. Think about a tadpole the next time you feel bogged down. They start out with gills and a tail but no legs and they must stay in the water. Then they begin to sprout legs, their tails shrink, and lungs form as their gills are absorbed into their bodies. One day they leave the water and hop about on land. Now that’s miraculous.