Frog Calls, February 2013
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Transcript of Frog Calls, February 2013
Frog Calls February, 2013
Page 1
Frog CallsNewsletter of Crosstimbers Connection
v Volume 1, No.1 v February, 2013 v
Welcome to “Frog Calls”!We are glad you are reading this issue of Frog Calls, the newsletter of Crosstimbers Connection. In these
pages, we’ll tell you what we have been doing, and what we plan to do. We hope you will plan to join us
for a field trip! We will also include some stories about the wonderful places and animals found in
north Texas.
Who is Crosstimbers Connection? We are a small
nonprofit organization started by people who have spent many years in the woods, creeks, and forests of
north Texas. Several of us have served for years with
the Dallas-Fort Worth Herpetological Society, going on field trips and providing educational events for
the public. We believe that spending time in nature is exciting and fun, and that we can learn a lot about
the world around us when we go for a walk in the woods. To ask about one of our field trips, just
contact us through our website.
Frog Calls can be downloaded from our website,
www.crosstimbersconnection.org, or it can be emailed to you if you let us know you would like to
get it.
Reptiles Up Close
On February 23, we took our stories, photos, and some harmless reptiles to Riverside Community
Center in Fort Worth, to the Get Outside Fort Worth (GO FW) club. There were lots of slides of some
beautiful prairies, woodlands, and wetlands, along with equally beautiful slides of the reptiles and
amphibians that live there.
We talked with thirteen kids and six adults, and
started making some plans for a follow up field trip to the Fort Worth Nature Center and Refuge. Jocelyn
Kids at the GO FW club learn about the nature of north Texas
Continued on page 2
Jocelyn and her dad check out a three-toed box turtle
Frog Calls February, 2013
Page 2
and her dad got a chance to meet a three-toed box turtle. Mark Pyle showed them this shy turtle, which
stayed mostly closed up in its shell. Andrea and lots of other kids enjoyed seeing a speckled kingsnake
and several other harmless snakes. Mark also showed them a glass lizard, which is an unusual
lizard that has no legs and moves around somewhat like a snake.
The GO FW program is a free family nature club that provides monthly informal outings where
people are welcome to come and go as they please. (To contact the GO FW program, call
817-871-7670)
Reptiles Up Close, continued
Andrea makes friends with a speckled kingsnake
The Web of Food that Supports Life
It all started with grass. Fresh, new shoots of the kinds of grasses that grow on the prairie. Grasses
with names like bluestem, indiangrass, and sideoats grama. And because of grass and other green plants,
a hawk soars in the skies of north Texas. And also because of these grasses, a bullsnake cruises along
the prairie at sunset in the last rays of sunlight.
In fact, maybe we should say that it all started with
those rays of sunlight. After all, it is the energy in sunlight that green plants use to make food for
themselves. Then if we eat the plant, it becomes our food. We eat spinach, squash, carrots, and other
plants to get the food they created using sunlight. And lots of animals, like rabbits, grasshoppers, or
deer, eat plants as a source of food.
Some of those prairie grasses were eaten by a grasshopper. A little, green grasshopper that was just
a little too slow. If it was faster, it might have hopped away from the whiptail lizard that thought it would
make a tasty treat. As it was, the lizard pounced on the grasshopper and ate it. It ate dozens of other
insects that day, and since each insect had stored the energy from the plants it had eaten, the lizard was
benefiting from all that food created by the bluestem and the indiangrass.
Nearby, a couple of northern pygmy mice were nesting under some old cactus pads from a prickly
pear cactus. These little gray mice had grown up on a diet of plants, and they especially liked small
seeds. It also happened that a western coachwhip
Michael Smith
Frog Calls February, 2013
Page 3
snake was prowling around the area,
looking for food. This long, slender
snake had large bright eyes and
would raise the forward part of its
body from time to time and look
around, flicking its jet black tongue
out to pick up a “taste” of its
surroundings. It used everything it
could see and smell to know if
food - or danger - was nearby. Picking up traces of the nearby mice, it poked its head into the burrow
under the cactus pads. The snake grabbed the first mouse and pinned it against the ground and ate it,
as the second mouse escaped out another opening to its burrow.
One pygmy mouse was not much of a meal for a full-grown coachwhip, and so it continued its search. Five
feet of sandy light brown scales slipped around clumps of grass and rocks, as its reddish brown head
looked this way and that. The coachwhip spotted the whiptail lizard, and the chase was on. Both reptiles
were agile and quick, and the whiptail could dart ahead and suddenly stop, becoming nearly invisible
in the tangle of grass. Its dark body had light yellow-green stripes which blended in with the grasses and
made it harder to make out the outline of its body. The slightest movement would trigger another dash
by the lizard, running in a blur of speed for another
eight or ten feet. But ultimately, it could not outrun the coachwhip, and the snake got another meal.
The body of the lizard had been fed by many insects, and most of the insects were plant-eaters. The
energy of all those plants, passing through the insects and then the lizard, was used by the snake to
grow and to chase down more food.
But that was not the end of the story. A few weeks
later, the coachwhip was once again slipping through the grasses and poking its head into burrows or
under rocks, looking for food. Thirty yards away, perched on the high branches of a live oak tree, a
red-tailed hawk looked out across the field. The hawk’s keen vision spotted movement. A long snake
was moving among the grasses and rocks. The bird took to the air, silently swooping toward the snake.
At that moment, the coachwhip pulled its head back from where it had been checking an old mouse
burrow, and caught sight of the hawk. It made a
The Web of Food, continued
Western coachwhip (photo by Mark Pyle)
Frog Calls February, 2013
Page 4
frantic dash toward the edge of the woods, and as the hawk got close, the snake turned hard to the left
without slowing down. The hawk used its powerful wings to pivot in mid air and drop on to the snake.
Strong talons and a sharp beak ended the snake’s life, and the hawk almost immediately rose into the
air and carried the coachwhip’s body up to a safe perch for a leisurely meal.
The food had started in the leaves of plants, and then was used by insects or mice. It passed from these
animals to lizards and snakes, and finally to a hawk. Anything that harmed the plants could, in turn, affect
a great many other animals, even the ones that do not eat plants. In one way or another, plants and
animals are all linked in this way. Grasses and herbs feed cotton rats that are in turn eaten by that
bullsnake that we mentioned earlier. A coyote might also eat the cotton rats (and perhaps the bullsnake).
When biologists talk about how energy is passed from the plant up through the insect, to the lizard, to
the snake, and to the hawk, they describe it as a “food chain.” Each link in the chain is a plant or
animal. The grass is one link, and the insect is another. The lizard is a link further up the chain,
followed by the snake and finally the hawk.
Any prairie or forest or pond has many of these links
at each level, and so biologists talk about a “food web” of plants and animals that are all connected
to each other. The plants do not just support insects, they are food for rats and mice, rabbits,
deer, and other animals. Some animals take food at different levels - for example, box turtles may
eat green plants, mushrooms, fruit, insects, and may feed off the bodies of dead animals.
Sometimes it’s sad to think about how our favorite kind of animal is killed in the wild. Snake-lovers
may not like it that hawks eat snakes. Many bird-lovers are unhappy that some snakes such as
Texas rat snakes eat birds. It may be helpful to remember that this is part of the big picture in
which everything participates in a food web that supports all life.
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, learning and having fun. And we do it without charging anything (but we gladly accept contributions to keep us going). We are a nonprofit organization - please visit us on the web at: http://crosstimbersconnection.org.
Michael Smith, President - [email protected] Rob Denkhaus, Board MemberMark Pyle, Vice President - [email protected] Kaydee Doss, DocentDebbie Dorman, Secretary/Treasurer - [email protected]
P.O. Box 151882 h Arlington, Texas 76015
The Web of Food, continued
Ornate box turtle, eating a grape (photo by Michael Smith)