Background for Teachers
What's a Wetland?
Wetlands fall somewhere between land and water, hence the compound word: wet + land. They mark the place where two habitats interface, or where earth and water come together. When a terrestrial habitat and an aquatic one come together it creates a unique habitat all its own, the wetland habitat.
Throughout work on this topic, help your students understand:
- what a wetland is and that wetlands are not always wet (many wetlands are only seasonal)
- that wetlands can be found in every part of Texas.
- that Texas has two main types of wetlands: freshwater and coastal.
- that wetlands are places where species diversity is high.
- that wetlands often serve as transitional zones between land and water (especially coastal wetlands).
- that wetlands help us in many ways including protecting water quality, providing wildlife habitat, and providing flood control.
- that lakes aren't considered wetlands because they are too deep. A wetland will usually need to be shallow enough to support wet-footed plants.
- that wetlands are often undervalued because they aren't always the prettiest landscapes.
Wetlands come in many varieties. Wetlands across Texas are featured in this 12-page book that can be downloaded from the TPWD Web site, or you can order free copies by emailing firstname.lastname@example.org
This 15-page book (text and illustrations) created by the Army Corp of Engineers is full of great lessons and coloring sheets.
Ducks Unlimited Resources
These are extensive, but excellent, resources brought to you by Ducks Unlimited:
- Student Journal: http://www.greenwing.org/dueducator/ducanadapdf/99993845.PDF
- Educator’s Manual: http://www.greenwing.org/dueducator/ducanadapdf/99993846.PDF
Why Wetlands Are Wonderful
The key to understanding why wetlands are so important is understanding the food chain (some call it a “food web”).
In wetlands, critters that form the basis of the food chain (some of them microscopic) have such ripe conditions in which to develop that they flourish. Since they flourish, the foundation upon which the whole chain is built is strong.
Detritus (dee-try-tus) is a cornerstone of this foundation. Dead leaves and stems break down into particles that become detritus. Microscopic critters, bacteria and algae begin the process of decomposition. In addition, small animals like insects, mussels, crawdads, certain kinds of fish, and shellfish feed on the detritus and continue processing it. These animals, in turn, become food for other animals such as egrets and other birds. Birds become food for animals such as alligators. You can see how the cycle begins and continues.
Students were directed to this website to learn more about food chains and you will likely enjoy this entertaining review as well: How Wetlands Benefit Us
In the Student Research Page the students are taught the meaning of the word “benefits.” You might take this opportunity to teach/re-teach the meaning of the prefix “bene,” which means "good."
Ask your children to share their thoughts, opinions, and stories with regard to the following benefits provided to us by wetlands. http://www.sheppardsoftware.com/content/animals/kidscorner/foodchain/producersconsumers.htm
First, study “America’s Wetlands” from the Environmental Protection Agency. This is a great way for you to learn more so that you are better prepared to guide the discussion.
- Wetlands benefit us because they help protect our property and our health!
- Wetlands benefit us because they give us places to have fun!
- Wetlands benefit those who like to watch all the cool things that wildlife do!
- Coastal wetlands benefit Texas shrimpers and fishermen!
Further Discussion For Kids Who Enjoy a Challenge:
Some people think of wetlands as wastelands because sometimes they’re the kinds of places that attract mosquitoes or have unpleasant odors due to standing water. What could you do to educate people about the benefits provided by wetlands? How could you convince them not to destroy them?
In Texas, a large number of freshwater wetlands are temporary. Vernal pools, puddles that stick around for a couple of weeks or more, are perfect examples of temporary wetlands.
Think of freshwater wetlands as giant sponges. When it rains, not all water can soak into the ground. Wetlands give the water that doesn’t a place to hang out.
Freshwater wetlands may also be known as “inland wetlands.”
Coastal wetlands may also be known as “tidal” or “estuarine” wetlands. This is where fresh water from rivers meets up with salty water at the coast, in our case, the Gulf of Mexico.
How much salt the water has dictates what kinds of animals will live in a coastal wetland. Only certain kinds of plants and animals can tolerate brackish water. Some coastal wetlands have more salt in them than others so species will vary.
Yet another name used for a coastal wetland is “salt marsh.” Marshes are wetlands that don’t have trees. The salty water makes for difficult growing conditions so, in general, you won’t see as many plants in coastal wetlands as you will in freshwater wetlands. Sometimes, however, you will see grasses growing throughout their shallow waters.
Fiddler crabs and marsh grasses have a special relationship whereby the crab’s tunneling system helps aerate the grasses’ roots. Just as we aerate our lawns to help oxygenate the roots, the crab’s tunnels help oxygenate the grass’s roots.
Special Texas Wetlands
ENCHANTED ROCK STATE NATURAL AREA
Enchanted Rock, near Fredricksburg, has very special kinds of wetlands called “vernal pools” where tiny fairy shrimp live. The official Department of Interior status of fairy shrimp is “threatened.”
- Fairy Shrimp: http://www.fws.gov/oregonfwo/species/data/vernalpoolfairyshrimp/
- Vernal pools: http://www.vernalpool.org/vpinfo_1.htm
- Enchanted Rock State Natural Area
- The vernal pools at (PDF)
BIG THICKET NATIONAL PRESERVE
- Big Thicket: http://www.nps.gov/bith/index.htm
- Pitcher Plant: http://www.botany.org/carnivorous_plants/
CADDO LAKE STATE PARK
Each year more Panhandle playas get converted into croplands since these temporary wetlands have very fertile soil. Some reports say there are 60,000 playas while others say there are only about 19,000 left. The 19,000-figure is likely a more accurate reflection of the true number of playas left. What we do know for certain is that we do not have near the number of playas that we used to in the high plains region.
The playas provide important resting places for the millions of migrating birds that travel through Texas each year. They also create the region’s richest habitat for its year-round residents, those with and without wings.
The non-profit Playa Lakes Joint Venture has been quite successful in preserving many of the playas. Check out their website to learn more about their work: http://www.pljv.org/about/history.
To learn more about our Texas Panhandle playas visit these sites:
BRAZOS BEND STATE PARK
- Brazos Bend State Park
- George Observatory
- American Alligators, National Geographic: http://animals.nationalgeographic.com/animals/reptiles/american-alligator.html
GREAT TEXAS COASTAL BIRDING TRAILS
ESTERO LLANO GRANDE STATE PARK
Estero Llano Grande is the geographic center of the “World Birding Center,” an area renowned for its incredible bird-life.