The Comal Springs is an aquifer springs that is a result of the Edward's Plateau that divides central Texas. It is nestled between Austin and San Antonio in the old German town of New Braunfels, Texas. There are nineteen different springs along the cliffs that form the river. The flow is at 50,000 gallons per minute and is rich in minerals from the layers of sediment that it seeps through which forms the underground watershed. The river is only seven miles long before it joins the Guadeloupe River.
The Comal Springs has very distinct characteristic, which do not occur in other rivers. The combination of rich nutrients, clear - flowing water results in a variety of algae and aquatic plants which forms the base food for the many different forms of aquatic life. These range from Insect larva to the Mollusks which are snails and clams, the Crustaceans which has six distinct crayfish and has an unusual prawn is a fresh water shrimp with has long pinchers.
Another is the fish population that is abundant in different types that range from minnows, to the known perch and bass, to the carp, crappie and catfish. The first mile of the spring is set aside as an environmentally sensitive zone where there are bird hatcheries. There are several springs that can be seen where the algae and plant life start to creep up the flow towards the source. The temperature of the water maintains a 68-degree range year round. This is a result of the water flowing from the ground water system. With this constant temperature, the aquatic plants are diverse in shapes and colors throughout the year. The different phases of the moon will effect the activity of the natural life, such as crayfish and the catfish. The most abundance of activity is the new moon where the darkness is the dominant feature.
The first items for divers to discover are the diverse variety of algae and aquatic plants. This grouping of water fauna stores energy from the sunlight with nutrients and minerals that come from the ground water system. The selection of the algae ranges from rock attaching types, to those that cover mud and dead shells. Each has a specific need for forming its attaching mechanism. The plants are specific in the need for having a rooting system and must have a soil to generate certain chemical needs. The diversity of the plant life range from grasses, to segmented stalked forms, to the more known broad leaf lilies. The flowers that occur Underwater can be more diverse and adds to the excitement of the river. These plants and algae's provide the base for the herbafors or plant eaters in the water. When looking close at the base, stack and leaves the variety can be observed, from the tiny baby snails, to the crayfish and fish, to the larva stages of many insects. Most of the algae feeder are about 1/8th to a 1/4 inch in size. The larger the animal grows the more diverse the different food sources become, for example the crayfish will mostly feed on certain species of algae as a main diet which is determined by each different type of crayfish. As they grow larger they broaden the diet by becoming carnivorous and feeding on other aquatic animals, dead or alive. Another important role that aquatic plants play is that of removing the carbon from the oxygen molecules which are release back into the water and stores the carbon along with other minerals in its roots. This then forms the bases for habitat of more life either being more plants or a shelter for small aquatic life to hide.
As for the crayfish and prawns, the species varies from a half-inch , to common crayfish of 4 to 6 inches, which varies in color, size and shape of the claws. The prawns that can be up to 19 inches long, hide in the crevices of the sandstone and are primarily natural or night grazers. The prawns are curious creatures, if a diver waits outside the entrance to the hole and taps on their tank, the prawn will slowly come out and the diver can observe the animal up close.
Mollusks are the snail and clams. Snails populate the plant leaves and serve to keep the algae and parasites under control. These groups of maids traverse the leaves vacuuming the surfaces where the plants can maintain its proper functioning. The clams traverse the sediment, borrowing their bodies and shell to conceal them from being the primary diet for turtles. The siphon is the mouth which rotates around the borrow, slurping up the algae which propagates on the dark mud deposits of the plants. There are four different species of clams in the river.
There are many other organisms like bacteria and fungus which also sways in balance with the plants and animal life, however the ecology of the river is dependent on certain balances of plants and animals which gives habitat for all other life forms.
The fish life of the river is very diverse. The perch family is divided into seven different species, which includes the colorful Pecos perch. This group feeds on small snails, insect larva, the small crayfish and fish. This group stays in-groups and has territories. Most can be observed closely when they spawn and hover over a gravel circle protecting the eggs or fry. The female perch is the large and colorful, whereas the male will be half the size and dull in color. The fins mostly distinguish identification of the different species, gill shape and the jawbones. Next is the four species of black bass, which feed on the crayfish and the juvenile perch.
This group hides in the shadows of the aquatic plants and behind logs waiting for a easy meal which might drift by. Another group is the carp group that can be as large as 35 pounds. The carp family is a scavenger and algae feeder like the parrotfish on a reef. Carp graze the mud for algae, worms and small snails. The catfish of the river varies with five different families. They are night feeders and live in the holes along the banks or under rocks. Their diet is mostly small fish and crayfish that might pass the entrance of their home at night.
Divers can observer the perspective of how sensitive this aquatic system can be by entering and exiting at the steps, watching and being careful not to disturb the growth or mud.
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