Food Webs of the Ogeechee River
Background Information: The Ogeechee River is a 245 miles long black-water
river. It begins with spring-fed streams 650 feet above sea level in Green County,
Georgia and increases in volume as it flows south, through the Piedmont to the fall
line. As the river flows over the fall line, it enters the Upper then Lower Coastal Plain
where it increases in volume, depth, and width. Below Millen, GA, the river cuts through sand and clay
bluffs which provide dry areas for boaters, fishermen, and picnickers to camp. The Ogeechee River is
joined by the Canoochee River northwest of Savannah, and then meanders through salt marsh until it
enters the Atlantic Ocean.
The Ogeechee River provides food, water, and shelter to a variety of plant and animal species.
The Ogeechee has been the source of much controversy as a large fish kill alerted the public to the
possibility that the river and its inhabitants had been the victim of point-source pollution – a textile
industry involved in the treatment of fabrics has been identified as releasing toxic chemicals into the
river. The chemicals are thought to have weakened the fish’s immunity, allowing a bacterial infection to
kill an estimated 33,000 fish.
Source: http://www.sherpaguides.com/georgia/coast/northern_coast/ogeechee_river.html; http://www.ogeecheeriverkeeper.org;
http://www.kamfin.com
Purpose of this Activity: To show energy flow through an aquatic ecosystem by constructing a model
food web and to predict what might happen in one organism is removed from the food web by human
activities (destruction, pollution, etc.)
Materials: handouts of printed plants and animals found in the Ogeechee River, handout list of these
organisms, scissors, glue, colored pencils or markers
Methods: You and your partner will create a picture of the Ogeechee River showing examples of food
chains and webs that could be found in this aquatic ecosystem. You should perform the following:
STEP 1: Complete the handout list of the organisms found in the Ogeechee River by naming probable
food sources for each organism and filling-in the center column. You and your partner will need to use
prior knowledge or internet research to identify these food sources for each organism. Then you and
your partner will label each organism as a producer, herbivore, omnivore, carnivore, and/or decomposer
based on their food source. In the column labeled “Symbol”, add the correct symbol for each organism’s
food source (more than one symbol may fit some organisms):
a. Producers = P
d. Carnivores = C
b. Herbivores = H
e. Decomposers = D
c. Omnivores = O
*Note: I left blank cells in case you and your partner would like to add appropriate organisms to
this list that you feel are important in this ecosystem!
STEP 2: Use scissors to cut the organisms from the handout of the plants and animals found in the
Ogeechee River
STEP 3: Create a food web that begins with the sun and contains multiple producers, consumers, and at
least one decomposer. Paste your food web on the provided blue paper. Using colored pencils or markers,
draw arrows to show how energy is passed from one source to another. Remember arrows go from the
organism that is eaten to the organism doing the eating!
*Note: I provided an extra copy of a few of the organisms to aid you in completing the food web.
STEP 4: Once your picture is done, put you & your partner’s name & period on the bottom of the page.
ASSESSMENT: ANSWER THE FOLLOWING QUESTIONS ON A SEPARATE SHEET OF PAPER IN
COMPLETE AND DESCRIPTIVE SENTENCES!:
1. What is the original source of energy for this and any food chain or web?
2. What is the process performed by producers that convert this original energy into usable energy?
Write the full equation.
3. What is the chemical process that changes food (sugar) energy into usable energy? Write the full
equation?
4. In what ways do producers and consumers use energy, i.e., what life activities or processes do plants
and animals perform that require energy?
5. Give an example of a primary (first level) consumer from your food chain. Is this organism an
herbivore, carnivore, or omnivore?
6. Provide an example of a tertiary (3rd level) consumer from your food web. Is this organism an
herbivore, carnivore, or omnivore?
7. Provide an example of a decomposer from your food chain or web.
8. Why are decomposers so important to ecosystems?
9. Explain what may happen to the other organisms if toxins were to kill the fish in your food web.
Which organisms would increase in population and why? Which organisms would decrease in
population and why?
10. What other activities, other than releasing toxic pollution, do humans do that might affect the food
chains and webs in this aquatic ecosystem?
Assignments due:
1. Organisms Found within the Ogeechee River handout completed by you and your partner in which
you names food sources and identified their feeding level for the many organisms found in the
Ogeechee River (with both partners’ name on it)
2. Picture completed by you and your partner showing a food web that can be found in the Ogeechee
River (with both partners’ name on it)
3. Assessment Questions answered on a separate sheet of paper (with both partners’ name on it)
Staple all three pages together and turn them in for a LAB GRADE!
Name(s)___________________________________________________ Period _______ Date _________
Food Webs of the Ogeechee River: Organisms Found within the Ogeechee River
ORGANISM
FOOD SOURCE
SYMBOL
Algae
Alligator
Bacteria
Cypress tree
Bald Eagle
Banded water snake
Beaver
Black Willow tree
Blue Gill Bream (fish)
Bull frog
Catfish
Cottonmouth (Water Moccasin)
Dragonfly
Eel (freshwater fish)
Great Blue Heron (bird)
Largemouth Bass
Kingfish (bird)
Mushrooms (on bank of river)
Osprey (bird)
Phytoplankton
Raccoon
Symbols: Producers = P, Herbivores = H, Omnivores = O, Carnivores = C, Decomposers = D
ORGANISM
Red-eared slider turtle
FOOD SOURCE
SYMBOL
Red Maple tree
River Birch tree
River Otter
Common snapping turtle
Water Lily
Water Oak
Wood Stork
Zooplankton
Another Organism You’d Like to
Add:
Another Organism You’d Like to
Add:
Another Organism You’d Like to
Add:
Another Organism You’d Like to
Add:
Symbols: Producers = P, Herbivores = H, Omnivores = O, Carnivores = C, Decomposers = D
BACTERIA
BALD EAGLE
BANDED WATER SNAKE
RED-EARED SLIDER
BLUE GILL
WOOD STORK
BEAVER
KINGFISHER
ALGAE
BULLFROG
ALLIGATOR
EEL
RIVER OTTER
WATER OAK TREE
RIVER BIRCH TREE
BALD CYPRESS TREE
RACOON
ZOOPLANKTON
COMMON SNAPPING TURTLE
PHYTOPLANKTON
LARGEMOUTH BASS
BLACK WILLOW TREE
OSPREY
CATFISH
WATERLILY
MUSHROOM
CRAYFISH
DRAGONFLY
GREAT BLUE HERON
MUSHROOM
PHYTOPLANKTON
RED MAPLE TREE
ZOOPLANKTON
COTTONMOUTH
Ogeechee River Poster
Poster Completed by: ___________________________________________________________________
Name(s) ___________________________________________________Period_______Date _______
Ogeechee River Fish Kill Extra-Credit Assignment
Use the Internet and local newspapers to research the Ogeechee River fish kill that occurred summer
2011. Provide information about the following:
1. What explanations have been proposed for this fish kill? Is this a natural or human-caused
occurrence? Explain.
2. Can any one specific organization (private industry, federal, state, or local government agency) be
blamed for this environmental problem? Explain.
3. What environmental laws or regulations apply to this event? After researching the fish kill, would
you make any changes in our current environmental laws? If so, what would you change?
4. Has this activity or the information you found online changed the way you may use the Ogeechee
River in the future? If so, how?