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Frog Calls March, 2015
Newsletter of Crosstimbers Connection
Mark April 25 in your calendar!
A Celebration of the Prairie Let’s take a walk down a winding trail through tall grasses and spring flowers, down through patches of juniper and back up a limestone-studded hillside. Let’s see if the Texas spiny lizards are busily catching insects and scampering up the trees or shrubs to bask in spring warmth. Let’s go to the 10th anniversary of Prairie Fest!
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So me gre at e ve nt s f or th e spring! Let’s get spring started! From native fish to a celebration of the prairie to snakes of north Texas, we have lots to offer this spring.
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Th e real fr og calls
Our newsletter is named for the sometimes beautiful, sometimes strange calls of frogs. Let’s talk about the real calls of real frogs and toads.
Prairie Fest showcases the Tandy Hills Natural Area in east Fort Worth, and celebrates the native prairie that once dominated the north Texas landscape, between the cross timbers forests. You can learn more about Prairie Fest at http://www.tandyhills.org/fest. Crosstimbers Connection will be there, along with lots of other organizations, educators, and entertainers, from 11:00am through the afternoon. Come on out, see all the booths and displays, listen to music, and take a walk through the prairie.
Frog Calls
Spring Events All of ou r event s ar e free, but the host l ocat ion m ay cha rge a n ent ra nce fee – check t hei r w ebsite t o see if ther e is a fee.
Fish of th e We st Fork of the Trinity River M arch 8 , fr om 2 :00- 3: 00pm , at Fo rt Wo rth N ature C ente r & R ef uge , H ard wicke Inter pretiv e C e nt er (see h ttp://ww w.f wnature center .o rg ) Come join us and learn about the fish you might find on a visit to the west fork of the Trinity River! See which of our native fish hang out near the surface and which ones lurk in deeper places. This presentation will feature interesting facts about the fish and we will look at photos and talk about how to identify them, learning what separates the shiners from the sunfish!
Snakes of North T exas M arch 1 3, f ro m 11: 00am - 1: 00pm , at Do gwoo d C anyo n A ud ub on Ce nt er (see h ttp://ww w.d o gwo o dc any on.aud ub o n.or g ) We’ll have lots of slides and information about venomous and nonvenomous snakes of our area. We'll also have a few native non-venomous snakes for you to see close up. And, the Dogwood Canyon Audubon Center is a great place for a hike either before or after, with trails that wind through forests and up onto a ridge top in the Cedar Hill area.
Prairie Fest 2015 (Se e p age 1 f or mo re d etails)
Venomous & Harmless Snake s (2 pre sentations) & Herp W alks! M ay 17 (ve no mo us), June 14 (nonv eno mo us ), bo th f rom 1 :0 0-2: 00pm FW N ature C ente r & R ef uge , Har dw ick e C enter (se e h ttp://ww w.f wnature center .o rg ) On May 17 come and meet, in pictures and stories, the venomous snakes of our area. Learn to identify them and discuss how to stay safe when you're outdoors. Then on June 14 hear about our non-venomous snakes, and meet a couple of them firsthand. On each date, after the talk is done we plan to lead a “herp walk” to see places where reptiles and amphibians live, and hopefully see a few and maybe take a photo or two. Come with us in search of turtles, lizards, snakes, and frogs, and learn about how to look for them.
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Frog Calls
Volume 3 No. 1 – March, 2015
Voices of the Night -- Michael Smith
“Waaaaaaaah!”
-- Dr. Archie Carr
When can you hear frog calls? Depending on the species, frogs may be calling almost any time of the year. The best overall time may be after spring rainfall, when many species are breeding.
Where can I find recordings of frog calls? The beautifully illustrated book, The Frogs and Toads of North America (by Lang Elliott, Carl Gerhardt, & Carlos Davidson) has an audio CD of nearly 100 North American frog calls. There is also a CD containing recordings of 41 frogs and toads in Texas, with a guide to interpreting frog and toad choruses. It is available for $5.00 from the Wildlife Diversity Program, Texas Parks and Wildlife (1-800-792-1112, x 8062).
In a very dark prairie night, this sound came to us from over a small rise. With its drawn out nasal tone, for a moment it suggested a baby in distress. Almost, but not quite. “Waaaaaaaah!” An answering call from nearby. If we did not know the origin of this strange, bawling sound, this would have been a very creepy experience. However, out here in mid-March, near where rainfall has collected in some small pools, we knew that the calls did not represent any real distress. Or maybe if you were a male Woodhouse’s toad, and it had been raining and you really wished the ladies would come out and play, maybe that would seem pretty distressing. “Waaaaaaaah!”
Woodhouse’s Toad (photo: Michael Smith)
“Frogs do for the night what birds do for the day... they give it a voice.”
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Frog Calls Voices of the Night - Continued from page 3
Near the edge of one of the temporary pools my flashlight found one of the toads, a rounded and mottled animal with small dark spots on a light tan-gray background, with a pale stripe down the middle of the back. Each time he called, his throat expanded like a balloon. His bright eyes, with their gold-rimmed oval pupils, stared into the darkness. Other males began to call, each long nasal call overlapping the calls of one or two neighboring toads. And then another note was added to the sound, a high-pitched droning call that sounded like an angry bee buzzing. I recognized this as coming from the western narrow-mouthed toad. It was amazing that a sound from such a tiny frog could carry such distances in the soft night air. Frogs and toads use their trills, chirps, and other vocalizations mostly during breeding activity. While a frog may have a distress call that
Boy Bands After it rains, areas near ponds and ditches may have loud concerts with various species of frogs and toads calling. At the right times and places, the noise may be pretty intense as the boys all sing their hearts out to attract the girls. The sounds of hundreds of cricket frogs may overlap with choruses of treefrogs, added to the drone of toads and the calls of leopard frogs and bullfrogs. Standing in the middle of all that on a summer night is a wonderful, overwhelming experience!
Leopard frog (photo: Michael Smith)
they use if they are grabbed, the choruses of frog calls we hear at night are males calling to females. When the female arrives on the scene, male frogs try to climb onto her back and hold on by hooking their front legs around her body. Usually he holds her just behind her front legs. This position is called “amplexus,” and it allows the male to fertilize the female’s eggs as she lays them in the water. The long “waaaah” call of the Woodhouse’s toad is like most other toad calls – a long and drawn out trill. Frogs, on the other hand, tend to have short, repeated pulses. For example, the spotted chorus frog’s call sounds a little like someone pulling their thumb over a comb repeatedly. The leopard frog has a series of chuckling sounds, often like, “chuck-chuck-chuckchuck-chuck.” The gray treefrog has a high call like short trilling notes on a flute. Frog calls come in a great variety of sounds, and few if any sound like the low croaks of frogs in cartoons.
Frog calls: usually consist of short, repeated sounds
Just as an experienced birder can recognize many bird species just by hearing their songs, we can identify many frogs and toads by carefully listening to their calls. In fact, one of the best ways of telling the gray treefrog from Cope’s gray treefrog is by listening to their calls. These two treefrogs look practically identical, but Cope’s has two copies of
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Toad calls:
usually consist of extended, continuous trills
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Frog Calls
Volume 3 No. 1 – March, 2015
Voices of the Night - Continued from page 3
each chromosome in each of its cells, while the gray treefrog has four copies of each chromosome in each of its cells. Externally, it is hard to see any difference between these two frogs, but you can easily hear the difference. Cope’s gray treefrog has a more rapid, non-musical call, while the gray treefrog has a slower, richly musical voice. The call of one of our commonest frogs may be hard
commonly heard around ponds and streams. Often, one brave male starts off, which triggers other males to join in, and soon there is a full chorus going. A grown cricket frog could easily sit on your thumb, but the call can be quite loud, especially if there is a large group of frogs.
Gray treefrog (photo: Michael Smith)
to recognize as a frog call at all. Cricket frogs have a quick, high-pitched call – sort of like “grick … grick … grick – grick – grick.” It sounds like two rocks being hit together, slowly at first and then faster. These frogs may call during the day as well as nighttime, and they are
How do frogs and toads make these calls? The sound is usually created when the frog forces air from the lungs through vocal cords, and into the vocal sac at the throat. Some frog species have a single vocal sac under the chin and throat, while others have pairs of vocal sacs at the back and sides of the head. Herpetologists have found that the calls can affect other males as well as females. Male frogs may use the loudness of other males’ calls to position themselves so that they are not too close to other males. Bigger and stronger frogs may have somewhat louder calls and females may be able to evaluate the “fitness” of the various males and move toward the best choices. In the frog dating game, a male often alternates his calls with that of surrounding males so that they do not overlap, and thus he gets a chance to be heard. The Texas Parks & Wildlife Department (TPWD) has a program called Texas Nature Trackers that encourages us to help keep track of species of concern. One part of that program is the Texas Amphibian Watch, which trains citizen scientists to identify frogs and toads by their appearance as well as their calls. These volunteers then collect data on the amphibians that they see and share that data with TPWD biologists. If you are interested, click here: http://tpwd.texas.gov/huntwild/wild/wildlife_diversity/texas_nature_trackers/ So, this spring, after it rains, if you are near a park, a pond, or anywhere that frogs and toads may live, listen carefully after dark to the voices of the night!
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Spring will be here before you know it! Get out to the park, the nature preserve, the wildlife refuges, the grasslands. Wade, swim, hike and climb! Don’t let the opportunity pass you by. Fro g Calls
Vol. 3 N o. 1 , Ma rch 201 5
Crosstimbers Connection Connecting People with Nature in North Texas We take people out into the woods and prairies, looking for reptiles, amphibians, and other wildlife. We also give presentations to bring the woods and the wildlife to the people with slides, stories, and animals. Additionally, we publish Frog Calls and the Post Oak & Prairie Journal to bring the natural places in Texas to life in print and photos. We do all this without charging anything (but we gladly accept tax-deductible contributions to keep us going). We are a 501(c)(3) nonprofit organization. Please visit us on the web at www.crosstimbersconnection.org. P.O. Box 151882 â?– Arlington, Texas 76015 On Facebook: www.facebook.com/CrosstimbersConnection