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Lakes and rivers

Back to the beginning
Visit Habitats: Estuaries

Lakes are bodies of water that are completely surrounded by land. They can be isolated where water flows into them but doesn’t flow out. Or they can be connected to other water systems where water flows into and out of the lake. Watch the video, then explore the lakes and river habitat screen below to learn more about what can be found in our lakes. You will find 23 clues to learn more about lakes and river habitats. This webpage is best viewed at a minimum width of 1250 pixels.

Take Quiz
https://www.sjrwmd.com/static/education/odyssey/natural-aquatic-habitats/GWO-habitats-401-intro-newFX.mp4

Sign with a question mark
Oxygen
Illustration of a palm tree
Producers

Illustrated moth

Insects

Illustration of the sun

Energy
Illustration of gray clouds
Air
Illustration of lily pads
Plants

Illustration of a fern
Photosynthesis
Sign with a question mark
Ecosystem
Illustrated otter
Otters
Illustrated Dragonfly
Dragonfly
Illustrated Aquatic Plants
Aquatic Plants
Manatee Sign
Manatee sign
Illustrated Manatee
Manatee
Illustrated Zooplankton
Zooplankton


Illustrated raccoon
Consumers
Illustrated mushrooms
Decomposers
Illustrated book
Book
Illustrated worm
Invertebrates
Phytoplankton illustration
Phytoplankton
Fish illustration
Fish
Vegetation illustration
Submerged vegetation
Underwater ecosystem illustration
Underwater ecosystem
Turtle illustration
Turtle

Visit Habitats: Estuaries

Illustration of a river

Oxygen

Plants use carbon dioxide and give off oxygen when they’re making food. Animals use the oxygen to live. What a deal!

https://www.sjrwmd.com/static/2020/07/4-1-055.mp3

Illustration of producers in this habitat

Producers

Producers are living things that make their own food by changing energy from the sun into food. Plants are producers. Examples of some producers in this ecosystem are cypress trees, aquatic plants and ferns.

https://www.sjrwmd.com/static/2020/07/4-1-051.mp3

Illustration of a fish eating a moth

Insects

Small organisms like insects are an important part of the aquatic food chain, because larger animals eat them, and then those animals are eaten by even larger animals.

https://www.sjrwmd.com/static/2020/07/4-1-058.mp3

Illustration of a food web

Energy

All living things need energy to live. Food chains, or webs, are used to show how energy moves through an ecosystem.

https://www.sjrwmd.com/static/2020/07/4-1-049.mp3

Illustration of a racoon breathing

Air

Do you use air? Of course you do. When you breathe, you take in oxygen that your body needs and you breathe out carbon dioxide that plants need to make food.

https://www.sjrwmd.com/static/2020/07/4-1-054.mp3

Illustration of sun rays shining on a plant

Plants

Plants are producers that change energy from the sun into food and provide energy for other living things through the food chains or food webs.

https://www.sjrwmd.com/static/2020/07/4-1-045.mp3

Illustration of sun shine shining on a fern

Photosynthesis

Plants use sunlight to change carbon dioxide and water into sugar. Mmmm. This process is called photosynthesis. Plants also use nutrients from the environment to make food. Did you know plants were so important? Wowee!

https://www.sjrwmd.com/static/2020/07/4-1-056.mp3

Illustration of animals and plants in an ecosystem

Ecosystems

An ecosystem is a natural community of living things that interact with each other and with non-living parts of the environment. Humans change ecosystems with their activities. Most people don’t realize that they’re a part of the ecosystem too. It took a long time for people to realize how human activities affect Florida’s ecosystems.

https://www.sjrwmd.com/static/2020/07/4-1-032a.mp3

Illustration of an otter holding a fish

Otters

Otters are consumers that like to eat fish. They use their webbed feet and thick tails to help them swim. They have to be quick swimmers to catch a fish.

https://www.sjrwmd.com/static/2020/07/4-1-061.mp3

Illustration of dragonflies flying around

Dragonfly

Dragonflies are insects that live in the water for part of their lives and out of the water for part of their lives. They’re important animals that are a part of the river and lake ecosystems.

https://www.sjrwmd.com/static/2020/07/4-1-057.mp3

Illustration of sunlight hitting a plant

Aquatic plants

Just like plants on land, aquatic plants use energy from the sun to make food. They use sunlight and nutrients to produce food and oxygen. Animals that live in the water use the oxygen to breathe.

https://www.sjrwmd.com/static/2020/07/4-1-044.mp3

Illustration of a manatee looking at a sign

Manatee sign

Manatees are large, endangered animals that live in Florida waters. They have big, flat teeth for chewing up aquatic vegetation. Some people call them sea cows.

https://www.sjrwmd.com/static/2020/07/4-1-059.mp3

Illustration of a manatee eating glass

Manatee

Manatees graze on aquatic vegetation in rivers and springs during cool winter months. During summer months, they graze in coastal seagrass beds. There’s even a seagrass called manatee grass.

https://www.sjrwmd.com/static/2020/07/4-1-060.mp3

Illustration of zooplankton

Zooplankton

Zooplankton are microscopic animals that have no backbone. Many other animals, like insects, do not have a backbone. These animals are called invertebrates. Zooplankton eat microscopic plants called phytoplankton.

https://www.sjrwmd.com/static/2020/07/4-1-048.mp3

Illustration of consumers

Consumers

Consumers are living things that get their energy by eating plants or other animals. Examples of some consumers in this ecosystem are manatees, otters, fish, turtles and dragonflies.

https://www.sjrwmd.com/static/2020/07/4-1-052.mp3

Illustration of decomposers

Decomposers

Decomposers are fungi, bacteria and insects that get their energy by breaking down wastes and dead organisms. They cause dead things to decay. Examples of decomposers found in this lake scene are the mushrooms.

https://www.sjrwmd.com/static/2020/08/4-1-053-shorter.mp3

Illustration of a manatee and microscopic organisms

Book

Living things, including people, depend on rivers and lakes that have good water quality. How do we know if a lake or river has good water quality? One way is to test the water for chemicals that are harmful to plants and animals. These chemicals are a type of pollution that may also affect the natural balance of the habitat. Another way to test for healthy water is to find out what’s living there. Scientists catch and count macroinvertebrates (MAC-row-in-VERT-ih-brates) to learn about the water quality of rivers, streams and lakes in Florida.

https://www.sjrwmd.com/static/2020/07/4-1-041a-combined.mp3

Illustration of a worm

Invertebrates

Worms are invertebrates. That’s what scientists call animals that don’t have a backbone. Invertebrates that can be seen without a microscope are called macroscopic invertebrates, or “macros” for short.

https://www.sjrwmd.com/static/2020/07/4-1-046.mp3

Illustration of Phytoplankton

Phytoplankton

Phytoplankton are microscopic plants, mainly algae, that float around in the rivers, marshes and lakes. Even though we can’t see them, these tiny plants are an important part of the ecosystem too.

https://www.sjrwmd.com/static/2020/07/4-1-047.mp3

Illustration of Fish

Fish

Many kinds of fish live in rivers and lakes. They come in all sizes and are a part of the food chain.

https://www.sjrwmd.com/static/2020/07/4-1-062.mp3

Illustration of submerged vegetation

Submerged vegetation

There are some plants that live completely under water. Where are they? Oh, there they are. Scientists describe these plants as submersed aquatic vegetation. Submersed aquatic vegetation grows in freshwater habitats like ponds, lakes and rivers. Some submersed aquatic vegetation is adapted to grow in saltwater habitats along the coast of Florida.

https://www.sjrwmd.com/static/2020/07/4-1-040.mp3

Illustration of an underwater ecosystem

Underwater ecosystem

Although you may not be able to see the plants that grow under water in rivers and lakes, they’re a very important part of the ecosystem. These plants provide food, shelter and even oxygen to animals that live in underwater habitats.

https://www.sjrwmd.com/static/2020/07/4-1-043.mp3

Illustration of a Turtle

Turtle

If you look closely, you might see a turtle searching the aquatic vegetation for fish and small animals to eat. Aquatic turtles normally surface to breathe air through their lungs, but some can absorb oxygen directly from the water through their skin or the lining of their throat.

https://www.sjrwmd.com/static/2020/07/4-1-063.mp3
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