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Estuaries

Back to the beginning
Back to Habitats: Lakes and Rivers
Visit Habitats: Wetlands


Find out more about what can be found in our estuaries by clicking around the screen. You will find 21 clues to learn more about estuary habitats. When you are finished with this page you can learn more about other habitats in Florida and take the quiz. This webpage is best viewed at a minimum width of 1250 pixels.

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Mangrove roots
Illustration of the Sun
Food chain

Illustrated swamp foliage

Saltmarsh grasses

Illustration of Mangrove trees

Mangrove trees
Illustration of a tall palm tree
Photosynthesis
Illustration of a short palm tree
Primary Producers
Illustration of a sing with leaves
Leaves
Illustration of a boat
Boat
Illustration of a dolphin
Dolphin
Illustration of tall grass
Producers
Illustration of
Consumers
Illustration of
Heron
Illustration of a sign
Habitat
Illustration of Mullet
Mullet
Illustration of Snook
Snook
Illustration of a Crab
Crab
Illustration of leaves
Decomposers
Illustration of Seagrasses
Seagrasses
Illustration of a Book
Book
Illustration of oysters
Oysters
Illustration of a group of oysters
Primary consumers

Visit Habitats: Wetlands

Illustration of a mangrove ecosystem

Mangrove roots

Wow! A mangrove tree is a busy place. The roots of the red mangrove provide a nursery area to young fish where they can find food and hide from predators. The roots prop up the red mangrove and provide a place for oysters, barnacles and other animals to attach and grow. Mangrove branches provide a place for birds to rest and nest.

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Illustration of producers in this habitat

Food chain

There are food chains in every ecosystem. People become part of the aquatic food chain when they eat fish, oysters, clams and other things from a lake, river or ocean.

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Illustration of producers in this habitat

Saltmarsh grasses

Saltmarsh grasses grow in areas around the estuary that are partly covered with water when the tide comes in and not covered when the tide goes out.

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Illustration of producers in this habitat

Mangrove trees

Mangrove trees grow along the shores of estuaries and provide valuable habitat for many animals. They can survive in the brackish water of the estuary.

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Illustration of producers in this habitat

Photosynthesis

All organisms need energy in one form or another, but only plants can use energy from the sun to make food. They use sunlight to combine water and carbon to manufacture food. Mmmm. Oxygen is given off when plants make food. Boy, plants are great.

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Illustration of producers in this habitat

Primary producers

Plants are called primary producers because they provide food for all animals. So many plants live in and around the estuary that there’s plenty of food for animals of all sizes.

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Illustration of falling leaves

Leaves

Mangrove leaves are tough, and difficult to eat. Not many animals will eat them on the tree, but when they fall into the water and begin to decay, the leaves become food for small fish and other creatures. The mangroves are primary producers. The decaying plant matter is called detritus.

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Illustration of producers in this habitat

Boat

The Indian River Lagoon is a very long, important estuary along the east coast of Florida. It’s home to more than 4,300 species of plants and animals, more than any other estuary in the United States.

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Illustration of a dolphin catching a fish

Dolphin

Dolphins are top consumers that come into the estuary to catch fish. They like to eat mullet because the mullet live in schools, and that makes them easier to catch.

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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 producers in the estuary are seagrasses and mangroves.

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Illustration of producers in this habitat

Consumers

Consumers are living things that get their energy by eating plants or other animals. Examples of consumers in an estuary are oysters, fish, herons, dolphins and crabs.

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Illustration of producers in this habitat

Heron

Blue herons are consumers because they cannot make their own food the way plants do. Consumers must get their food from either plants or other animals.

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Illustration of producers in this habitat

Habitat

A habitat is the place where plants and animals live and grow. Florida has many different types of habitats that provide the water, shelter, food and space needed by the living things found there. The amount of water available in a habitat is one thing that determines which plants and animals can live there.

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Illustration of producers in this habitat

Mullet

Mullet are called primary consumers because they eat plants called algae, and detritus. Many living creatures, including people, like to eat mullet.

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Illustration of a snook hunting mullet

Snook

Snook are called secondary consumers because they eat other animals.

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Illustration of a crab holding a leaf

Crab

Blue crabs are scavengers that will eat anything they can find, even decaying leaves called detritus and animal remains.

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Illustration of producers in this habitat

Decomposers

Decomposers are fungi, bacteria and insects that get their energy by breaking down wastes and dead organisms. They cause dead things to decay. An example of a decomposer in the estuary is the microorganisms found on detritus.

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Illustration of producers in this habitat

Seagrasses

Seagrasses are submersed aquatic vegetation that live in shallow salty water where there is plenty of light from the sun. These primary producers make food and provide shelter for animals that live in the estuary and for visiting animals that come just for food.

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Illustration of producers in this habitat

Book

Freshwater enters the estuary through rivers, creeks and canals. Salt water enters from the ocean through narrow opening between barrier islands that parallel the coast. The Indian River Lagoon seems like a river, but it’s not. Hundreds of miles of seagrass beds are found along Florida’s shores. Seagrass beds are submersed aquatic vegetation found in salty water. When healthy, these beds of seagrass provide food and habitat for a variety of wildlife, including fish, blue crabs, water birds and manatees. The seagrass beds also act as nurseries that protect and provide food for young fish and other animals. These grasses add dissolved oxygen to the water, which aquatic animals need to breathe. The health of seagrass beds can indicate the overall health of the aquatic system. An acre of healthy seagrass provides habitat for 50 million small invertebrates and 40,000 fish.

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Illustration of oysters

Oysters

Oysters are found stuck to a hard surface in oyster beds. Since they can’t move around to get food, they open their shells just a little and filter food out of the water. Can you imagine having to stay in one place your whole life?

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Illustration of oysters with their shells open

Primary consumers

Oysters are called primary consumers because they get their food by filtering the water. They are also called filter feeders.

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