Amphibians In Love
Mating Rituals of Frogs, Toads, & Salamanders

I suppose I can't really blame the police officer for questioning me. If I were in his shoes and had seen a grown man standing by the road on a chilly rainy night at the height of a terrorism alert, wearing waders and a headlight, and carrying some sort of odd contraption that looked more like a grenade launcher than anything you'd use to take pictures, I'd have stopped to ask questions, too. The only difference is that I'd have called for backup first. Probably the only thing that kept him from hauling me in was that my story was so bizarre he figured I had to be telling the truth.

"Let me get this straight. You're out here photographing frogs? At night? In the rain?"

I'm sure THAT made for interesting conversation during his next doughnut break.

My quarry wasn't just any old frog, mind you. I was after the northern spring peeper, Pseudacris crucifer crucifer, a thumbnail-sized amphibian with a voice as big as spring itself. Most everyone has their own harbinger of spring, that sight or sound that lets them know winter is finally relaxing its frosty grip. It might be seeing a particular wildflower blooming for the first time or witnessing a migratory bird returning to a feeder. For me, it is hearing the high-pitched chorus of spring peepers on the first mild nights of late winter. The celebrated nature writer Joseph Wood Krutch wrote of the spring peeper's call, "...I wonder if there is any phenomenon in the heavens above or in the earth beneath which so simply and so definitely announces that life is resurgent again." The symphony announces more to me than just warmer temperatures and unfurling leaves. It also tells me that love is in the air.

Spring peepers live out most of their lives in seclusion, hiding in the brush and leaf litter of woodlands. On rainy days in summer and fall, you might encounter one hopping about, but consider yourself lucky if you do. In winter, the tiny frogs seek out secure spots and go into a state of dormancy called brumation, which, unlike true hibernation, is merely a level of sluggish, reduced activity induced by prolonged periods of cold. They survive freezing temperatures by producing glycerol, a type of alcohol that acts like natural antifreeze (in fact, glycerol is a component of the antifreeze you put in your car). With the glycerol protecting its vital organs, more than half of a spring peeper's body can freeze without endangering it. Upon thawing, the frog goes on about his business as if nothing ever happened.

With the first warm rains of the year, the frog's "business" becomes a single-minded pursuit. The frogs are looking for love and they're not making any bones about it. Out of hiding they come, searching out woodland ponds, ditches, marshes, and flooded meadows, where, after dark, they fill the air with a cacophony of shrills and peeps. The singing serves two purposes: to stake out territory and to attract a mate. Males do all the calling (no surprise there), and they usually do so in groups of three. They produce sound by pushing air out of sacs in their throat and then drawing air quickly back in. When inflated, the sacs look like a chewing gum bubble about to burst. It's hard to imagine how such a loud, piercing sound could come out of that tiny little sac. Considering that the peeps can be heard more than a half-mile away, and that hundreds of males might be calling from a single wetland area no bigger than a tennis court, these little frogs rule the springtime airways.

The spring peeper's call is sometimes mistaken for that of insects, such as crickets or cicadas. Indeed, the genus name Pseudacris is Greek for "false cricket." While the sound might be similar in some respects, at the time of year when the spring peepers are out, most insects are still in their winter burrows or haven't yet hatched. The species name crucifer means "cross-bearing" and refers to the irregular-shaped "X" marking on the frog's back.

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While listening to a spring peeper symphony is a delightful experience, to enjoy the show fully you should watch them perform. This is admittedly easier said than done, as the little critters have a habit of shutting up at the first unnatural disturbance, and Homo sapiens clambering through the muck is about as unnatural as it gets for them. Still, by following a few simple guidelines (and perhaps utilizing a little trickery), you can enjoy a front-row seat at the concert on your first night out.

Slip on a pair of old sneakers and pants and grab a flashlight and camera for making photos. Waders are great if you're going to be crawling around taking pictures, but you don't need them for casual observing. If you have a miniature tape recorder, bring it as well. And bring the kids or grandkids. They'll have the time of their lives. Spring peepers live just about everywhere across North Carolina, so the trick to finding them lies in finding the proper habitat, rather than being in any particular part of the state. If possible, look for shallow ponds that dry up in late spring or summer, thus preventing fish (frog eaters) from becoming established. When I'm searching an unfamiliar area, I just drive around slowly with the windows down until I hear the peeps. Of course, you have to go out when the frogs are singing. That can be anywhere from late December along the coastal plain, to May in the higher elevations of the mountains. In the Piedmont, where I live, the concert usually begins in late February or early March. A few mild, sunny days to get the soil warmed up a bit, followed by a rain, will have them out in full force.

Once you've found a singing colony, it's just a matter of sneaking up on them as quietly as you can. They'll stop calling long before you get close to them, but that's okay. Remain still and they'll start back up shortly. If you brought a tape recorder, record a minute or two of the singing and play it back when they stop. That usually works to get them going again. Once you get close to the frogs, it may take awhile to spot one in the flashlight, as the little critters blend incredibly well with the vegetation and it's just about impossible to pinpoint the source of a call accurately. But once you do find one, you can often get as close as you like (but don't touch!) to take photographs. If he stops calling, just play the tape recorder until he starts singing again.

While the northern spring peeper is the most easily recognized (at least in voice) of spring's amphibian Casanovas, it's not the only critter out there with a love interest. Wood frogs, Rana sylvatica, are among the first to emerge from their winter dens, beginning as early as January. They occur only in the mountain and foothills regions of North Carolina, where snow and ice is often present as they reach their breeding ponds. With a low, ducklike quacking call that hardly carries beyond the breeding pond and a very short breeding period (rarely more than a week), wood frogs usually take care of their love affairs without being noticed by humans.

Spotted salamanders, Ambystoma maculatum, join the wood frogs as the "early birds" of amphibian courtship, emerging from their burrows with the first warm rains in January or February. These rather large salamanders have dark skin with yellow or orange dots on their backs. Although striking in appearance, few people have seen one since they spend most of their lives in underground burrows. Also, unlike most frog species, spotted salamanders go about their courtships in silence. You're much more likely to see the result of their affairs in the form of jellylike egg masses attached to roots and twigs in shallow pools. The spotted salamander is common over the piedmont and mountains of North Carolina, with scattered localities on the coastal plain.

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The amphibian most likely encountered in early spring is the eastern American toad, Bufo americanus americanus, a dark warty toad that lives in woodlands and gardens. It spends all of its life on land except for a brief breeding period during which it searches out shallow ditches, ponds, and placid sections of creeks. In the mountains, American toads seem particularly fond of mating in potholes along the edges of streams. The female lays a long string of tiny black eggs (a single clutch can contain 15,000 eggs), which take one or two weeks to hatch. American toads have one of the most pleasing of all animal calls, sounding something like the long trill of a cricket, but with a much more melodious tune. When several toads call together, as is often the case, the resulting chorus is one of nature's grandest performances.

The well-known bullfrog, Rana catesbeiana, lives out most of its live in or near the water. Its deep resonant call, like a sick bull bellowing from the pasture, is familiar to nearly everyone. The lesser-known pickerel frog, Rana palustris, and southern leopard frog, Rana sphenocephala utricularia, are unique in the frog world in both their appearance and call. The double row of squarish spots on its back, and scattered spots on the legs, make the pickerel frog one of our most handsome frogs. Its call sounds something like snoring coming from a person with a bad case of nasal congestion. Southern leopard frogs are similar in both appearance and call, but its spots are more irregularly shaped and its body color is deep green, rather than the brownish coloration of the pickerel frog. Both frogs are semi-terrestrial and travel a good deal away from water during the summer.

All these amphibian species are easily seen by someone willing to learn their habitat requirements and mating rituals, but that is not to imply that all amphibians are abundant and likely to take over the world. Indeed, all is not well in the amphibian world, with biologists throughout the world noticing marked declines of several species. In North Carolina, the 2001 Natural Heritage Program list of rare animal species records 24 species as occurring in small enough numbers to cause concern, 4 more than the 20 species listed in the 1995 edition. In this state and elsewhere around the world, numerous private and government agencies have begun studying the decline, and in 1991, the World Conservation Union established a global effort- the Declining Amphibian Populations Task Force. While no one knows for sure just what is causing such drastic declines in some amphibian populations (or even whether the declines are caused by man or are attributable to some sort of natural cycle), the research performed by these agencies will aid scientists as they seek to answer these questions and devise solutions.

We may not understand all the elements that contribute to hard times for our critters, but there are things each of us can do about it. A simple one is to avoid driving country roads on rainy nights in early spring, when salamanders and frogs migrate to breeding pools. And slow down during anytime of year, day or night (particularly when raining). We've all seen enough dead animals on the road to know this makes good sense.

Biologists don't have all the answers, but they do know that habitat loss is a major contributing factor in many scenarios involving species decline, both faunal and floral. With this in mind, another good thing you can do is support your local land conservation organizations. While I encourage people to join state and national groups such as The Nature Conservancy, local organizations such as land trusts often take an interest in smaller tracts, including those that wouldn't be of interest to a national group. In my neck of the woods, the Piedmont Land Conservancy has done an exemplary job of protecting local habitat. Its Ridges Mountain project, for example, has preserved a unique assemblage of upland breeding pools used by several species of amphibians.

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Some 80 species of amphibians live in North Carolina, in habitats ranging from the maritime forests of the Outer Banks, to the spruce-fir forests of our highest mountain elevations, to the subterranean darkness of our caves. Some live their entire lives underwater, while others only enter water to breed. Still others spend equal amounts of time both in and out of water. But come spring, most all of them share that primeval urge to seek out the opposite sex and reproduce. How they do it is the subject of endless wonder and amazement for all who witness it. Not even the Hollywood scriptwriters could come up with a story to top it.

So, the next time you want to take in a romantic show, drive past the movie theater and head for the amphibian love stage.