GeoCities.us
» RainForest » Wetlands|
GeoCities.us
» RainForest » Wetlands |
Get your FREE home page! |
 |
FROG WATCH
| [ Our Pond | Frogs by Their Calls | 1999 Calendar of First Calls | Why Frogs Matter | How We Listen | Be a Frog Watcher | Sofia & Mateo's Corner | Links ] |
|
Hello from the Stansfields! We live at the edge of a small town in southeastern Pennsylvania,
and behind our house, past the vegetable garden and the old fence, is a pond. It's not a big pond --
maybe half an acre, shallow at one end where the cattails are, with a wet, mucky woods on the far
side that floods every spring. When we moved here in the fall of 1996 we thought of it mostly as a
place the kids might fall into.
Then, one warm rainy night in March of '97, we opened the bedroom window and the noise was so loud we couldn't sleep. Thousands of tiny bells, all at once, like sleigh bells, coming from the pond. Carmen thought it was some kind of machine. It was spring peepers, and that was the night this whole thing started. Three springs later we know every frog that lives back there by its voice, we keep a calendar of when each one starts calling, the kids can tell a green frog from a bullfrog with their eyes shut, and we've turned into the kind of family that stands in the dark in rubber boots with a flashlight and a notebook. This page is how we keep track, and it's for anybody who's got a pond, a ditch or a wet spot nearby and wants to know who's out there singing. Who wrote what: Ray (Dad) did the frog descriptions and the science. Carmen (Mom) keeps the calendar and typed most of it. Sofia and Mateo have their own section at the bottom and wrote it themselves, mostly. |
| Frogs by Their Calls (Ray) |
|
Here's the thing about frogs: you almost never see them, but you can always hear them. Only the
males call, and each kind has its own call, so once you learn six or seven calls you can take a
census of a pond in the dark without getting your feet wet. Here are the six that live in our
pond, in the order they start up each spring.
1. Wood frog (Rana sylvatica) -- "quack, quack, quack" The first frog of the year, sometimes calling while there's still ice on the pond. The call sounds exactly like a duck -- a hoarse, clucking quack -- and the first year we honestly thought there were ducks in the woods at night. A tan or brown frog, two to three inches, with a dark "robber's mask" across the eyes. Wood frogs breed fast and early: they show up in the flooded woods on the first warm rainy nights of March, lay their eggs in big clumps in a week or two, and then they're gone back into the forest and you don't hear them again until next year. Here's the amazing part: wood frogs spend the winter under the leaf litter, and they freeze. Actually freeze solid, heart stopped. They thaw out in the spring and hop away. That's true. Look it up. 2. Spring peeper (Pseudacris crucifer) -- "PEEP ... PEEP ... PEEP" A high, clear, whistled peep, about one a second from each frog, and when a few hundred of them go at once the pond sounds like sleigh bells. This is the sound of spring in the East and it's LOUD -- you'll hear it from the car with the windows up. The frog itself is tiny, about an inch, tan with a dark X on its back (that's what crucifer means -- cross-bearer). They start in mid- or late March here and keep going into May. Look for the shiny throat sac puffed out like a bubble if you can find one with the flashlight. It's a treehog, and they climb into the shrubs at the pond edge to call. 3. American toad (Bufo americanus) -- "trrrrrrrrrrrrrrrrrrrrrr" A long, high, musical trill that goes on and on -- anywhere from six to thirty seconds without a break. Beautiful, actually; people are surprised it's a toad. Brown and warty, two to four inches, with the big bumps behind the eyes. Toads come to the pond in April to breed and lay their eggs in long strings (frog eggs are in clumps, toad eggs are in strings -- that's the easy way to tell). Then they go back to the garden, where we're very glad to have them; a toad eats a lot of bugs. And no, you can't get warts from them. 4. Gray treefrog (Hyla versicolor) -- "brrrrrrt" A short, loud, musical trill, about a second long, from up in the trees -- not from the pond. On a warm humid night in May or June the whole edge of the woods goes off. About two inches, with big sticky toe pads and rough skin, and here's the trick: it can change color from gray to green to nearly white depending on where it's sitting, which is why it's called versicolor. Bright yellow-orange on the inside of the thighs, which you see when it jumps. We find them stuck to the kitchen window at night, eating the moths at the light. (There's a look-alike called Cope's gray treefrog with a faster, harsher trill; we think ours are the regular kind but we're not sure, and the only way to know for certain is the call or a lab.) 5. Green frog (Rana clamitans) -- "GUNK!" Sounds exactly like somebody plucking a loose banjo string. One "gunk," or two or three in a row, going down in pitch. Green to brown, two to four inches, with a bright green upper lip on the males and -- this is how you tell it from a bullfrog -- two ridges of skin running down the back from behind the eyes. Green frogs call from the pond edge from late May right through August, and they're the ones that go "EEP!" and jump in when you walk along the bank. Very common. Ours live under the dock. 6. Bullfrog (Rana catesbeiana) -- "jug-o-RUM, jug-o-RUM" The deep, low bass note of a summer pond. You feel it as much as hear it. Our biggest frog by far -- the largest frog in North America, up to eight inches -- green with a big round eardrum behind the eye, and NO ridges down the back (the ridge goes around the eardrum instead). Bullfrogs start in late May or June and call through July. They eat anything that fits in their mouth: bugs, crayfish, other frogs, small snakes, once (Sofia saw this) a baby bird. Bullfrog tadpoles are huge and take two years, sometimes more, to turn into frogs, so we have tadpoles in the pond all winter. Others we've heard once or twice: a northern leopard frog (a low, snoring chuckle) in the wet meadow in April of '98, and something that might be a pickerel frog (a short, low snore) that we can't confirm. If you know how to tell the two snores apart, please e-mail Ray. |
| 1999 Calendar of First Calls (Carmen) |
The first night we hear each one. We've kept this since 1997, and it's turning out to be a pretty
good record of what kind of spring we had. The frogs go by temperature and rain, not the calendar,
so a warm wet March means an early peeper and a cold dry one means everybody waits.
1998 was the early year (that warm winter); 1999 was closer to normal, and the summer got so dry the shallow end nearly went to mud in August. We were worried about the tadpoles, but the September rain filled it back up. The fall quiet. By the end of August the pond is nearly silent -- just the crickets and katydids, and a green frog now and then. But here's something we didn't know until last year: on a warm, wet evening in September or October, you'll sometimes hear a spring peeper or two calling from the woods, way off, as if they've gotten the seasons mixed up. Nobody seems to know exactly why they do it. We heard one on September 19 this year, right after the rain, and Mateo wanted to know if that meant spring was coming. Not yet, buddy. It's on the calendar anyway. |
| Why Frogs Matter (Ray) |
|
Frogs are what scientists call an indicator species: a canary in the coal mine for the
health of a wetland. Two reasons. First, a frog's skin is thin and permeable -- it breathes and
drinks through it -- so whatever's in the water is soon in the frog. Second, a frog lives two lives,
one in the water as a tadpole and one on land as an adult, so it's exposed to trouble in both
places. If something's wrong with the pond, the frogs know first.
And for the last ten years or so, scientists all over the world have been reporting that frogs are in trouble -- populations shrinking or disappearing, even in places that look clean and protected. Nobody has one answer; it looks like several things at once, including habitat loss, pollution, disease and maybe changes in the climate and the ozone. A few years back, some schoolkids on a field trip in Minnesota found a pond full of frogs with extra legs and missing legs, and that got a lot of people paying attention. That's the big reason we keep the calendar. One family's pond isn't science by itself. But if a lot of families keep track of the same six frogs for a lot of years, then somebody someday can look at all the calendars together and see whether the peepers are starting earlier, or the wood frogs are disappearing, or the toads are doing fine. Which brings us to volunteering, below. The little reasons: a pond with frogs in it has a lot less mosquitoes, a lot fewer garden bugs, and a lot more herons, snakes and raccoons, which all eat frogs, which is how it's supposed to work. And it's the best free concert in the county. |
| How We Listen |
|
| Be a Frog Watcher |
|
There are volunteer frog-monitoring programs now, run through state wildlife agencies, nature
centers and some of the big conservation groups, where ordinary people -- families, scout troops,
retired folks, school classes -- agree to listen at the same wetland a few times each spring and
send in what they hear. Some use a tape of the calls to train you, and some have you learn a route
of several stops. It doesn't take any equipment beyond your ears, a notebook and a thermometer,
and the data goes to real scientists who can't possibly listen at every pond themselves.
We signed up for one through our county nature center in the spring of '98 and it's the reason our calendar got more organized. Ask at your nature center, your state wildlife or game agency, or the biology department at a nearby college; somebody will know who's collecting frog calls in your area. And if there's nobody, start your own calendar. Even a calendar on the fridge is a record. |
| Sofia & Mateo's Corner |
|
Sofia (age 10): My favorite frog is the gray treefrog because it can change colors and it has
orange on its legs like a secret. I found one on the window and it stayed there for three nights.
I named it Pancake. I am in charge of the thermometer. This year I also saw a bullfrog eat a baby
bird which was gross but Dad says that's nature. I want to be a herpetologist which is a scientist
who studies frogs and snakes and I can spell it now. I am doing my science fair project on how the
temperature changes when the peepers start. Dad is not allowed to help except for the graph.
Mateo (age 7): I like the bullfrog because it is the biggest and it says JUG O RUM. I can do the green frog. GUNK. I can do the peeper. PEEP. I can not do the toad because you have to hold your breath too long. My job is the notebook but Sofia says I write too big. I found 14 toads in the yard in June and I put them all back. One peed on me. I am going to be a frog scientist too or a fireman. Frog joke (Mateo): What do frogs drink? CROAK-a-cola. Frog joke (Sofia): What's a frog's favorite year? A LEAP year. (Y2K is not a leap year problem, Dad says. It is a computer problem. The frogs will be fine.) |
| Links |
Backyard Birds of Wisconsin -- Walt and June do for birds what we're trying to do for frogs. Our herons visit their page.
Monarch Waystation -- another backyard for wildlife.
Jake's Bug Collection -- Mateo's favorite page. Jake is 9 and collects the things our frogs eat.
Weather Watching with Walter -- a cooperative weather observer; we got our thermometer idea from him.
The RainForest neighborhood
|
Frog watchers who have hopped by since April 1999:   
E-mail the StansfieldsSend us your first-call dates! We'd love to compare calendars with other ponds. Ray answers the frog questions; Carmen answers everything else. 
Coming when we figure out the scanner: Sofia's drawings of all six frogs, and a map of the pond.
Last updated September 20, 1999 (added the fall peeper). © 1999 The Stansfield Family. |