Chesapeake Bay: US Coast Guard

The Chesapeake Bay Watershed Chesapeake Bay Watershed: US Department of Agriculture

Largest estuary in the United States Land and Ocean Meet Protected High Nutrients One of the most productive ecosystem in world! Bay Map: NASA Largest estuary in the United States

No other American estuary has a higher yield Fishing Industry of: No other American estuary has a higher yield Blue Crab Oysters Striped Bass Clams Blue Crab: The Children's Museum of Indianapolis Oyster: David Monniaux Striped Bass: Mike Smedley Clam: Aung/Wikipedia

Direct students to notice the green areas in the water Direct students to notice the green areas in the water. You can explain that these are large areas where algae is quickly growing (algal blooms). Ask Map: NASA The Bay Is Not Healthy

Nutrient Pollution Causes Algal Blooms and Fish Kills Algal Blooms: Jennifer L. Graham/US Geological Survey Nutrient Pollution Causes Algal Blooms and Fish Kills

Nutrients, Algae and Fish Kills Dead zones appear in the bay where nothing can live Low dissolved oxygen in the water kills fish and other organisms Microbes use the oxygen in the water Detritus is decomposed by microbes, microbe populations boom. Algae die and become detritus (decaying matter) Adding nutrients causes algal blooms In normal ecosystem low nutrient levels keep algae in check Dead Fish: US Geological Survey Fish kill caused by nutrient build-up, Nanticoke River, Chesapeake Bay, 1992

What causes the excess nutrients? Rivers and tributaries are bringing the nutrients to the Chesapeake Bay: Sewage Farming Factory farms discharge 650 million lbs of chicken manure each year Hog Farm Waste: USDA Chickens: SRAP Pigs: Farm Sanctuary

Have people played a role in changing the ecosystem to make it more vulnerable to algal blooms and dead zones? Longshoreman Atlantic City: Isabella & Carroll Walker Collection/The Norfolk Public Library

To Investigate this question you will: Analyze historic and modern day food webs Chart trends in harvesting and ocean health using real data on the Chesapeake Bay Draw conclusions from your analyses and make recommendations for restoring Chesapeake Bay ecosystems Watch a short film about the Chesapeake Bay and discuss your seafood consumption choices

Chesapeake Bay Food Web Before Large Scale Fishing Strong Interaction Weak Tertiary Consumers Secondary Consumers Consumers Producers Decomposers Abundant Rare Detritus Extinct Seals Sharks Whales- toothed & baleen Alligators Sea Turtles Birds Grazing Fish Predatory Fish jellyfish Predatory Invertebrates Manatees Oysters worms/ amphipods Zooplankton floating algae microbes detritus/decaying matter/nutrients Sea Grass Sea Floor Plants

Image Credits Chesapeake Bay: US Coast Guard Chesapeake Bay Watershed: US Department of Agriculture Chesapeake Bay Map: NASA Blue Crab: The Children's Museum of Indianapolis Oyster: David Monniaux Striped Bass: Mike Smedley Clam: Aung/Wikipedia Map: NASA Algal Blooms: Jennifer L. Graham/US Geological Survey Dead Fish: US Geological Survey Hog Farm Waste: USDA Chickens: SRAP Pigs: Farm Sanctuary Longshoreman Atlantic City: Isabella & Carroll Walker Collection/The Norfolk Public Library