CHESAPEAKE BAY. Chesapeake as an Estuary An estuary is a semi-enclosed body of water that has a free...

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CHESAPEAKE BAYCHESAPEAKE BAY

Chesapeake as an Chesapeake as an EstuaryEstuary

An estuary is a semi-An estuary is a semi-enclosed body of water enclosed body of water that has a free connection that has a free connection with the seawith the sea

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Chesapeake as an Chesapeake as an EstuaryEstuary

Estuaries have more food Estuaries have more food for organisms, but the for organisms, but the organisms usually have to organisms usually have to deal with large temperature deal with large temperature and salinity changes, high and salinity changes, high silt content and pollution.silt content and pollution.

Why do you think high silt Why do you think high silt would be a problem for would be a problem for

marine organisms?marine organisms? Hint Hint How How

does this does this organism get organism get its food?its food?

Many marine organisms are Many marine organisms are filter feeders so silt can be a filter feeders so silt can be a

major problem.major problem.

Many of these filter feeders Many of these filter feeders are important as food to are important as food to

humans.humans.

Colonization of EstuariesColonization of Estuaries

Estuaries are regions of Estuaries are regions of transition and sharp transition and sharp gradients.gradients.

Estuaries support fauna Estuaries support fauna recruited mostly from the searecruited mostly from the sea

The number of species in an The number of species in an estuary is greatly reduced, but estuary is greatly reduced, but the number of individuals is the number of individuals is large.large.

What does that mean? Can you What does that mean? Can you explain that last statement?explain that last statement?

The AnswerThe Answer For those For those

organisms that organisms that can survive the can survive the problems of problems of the estuary, the estuary, there is a great there is a great deal of food.deal of food.

The AnswerThe Answer

These These organisms organisms tend to be tend to be in large in large numbers.numbers.

Estuary TypesEstuary Types

The Chesapeake Bay is a The Chesapeake Bay is a drowned river valley.drowned river valley. This is This is the most common type of the most common type of estuary. It was formed during estuary. It was formed during the last ice age some 12,000 the last ice age some 12,000 – 18,000 years ago.– 18,000 years ago.

Estuary TypesEstuary Types The Chesapeake Bay is a The Chesapeake Bay is a drowned drowned

river valley.river valley. This is the most common This is the most common type of estuary. It was formed during type of estuary. It was formed during the last ice age some 12,000 – the last ice age some 12,000 – 18,000 years ago.18,000 years ago.

There are other types of estuaries. There are other types of estuaries. Can you name any of them?Can you name any of them?

Bar-Built EstuariesBar-Built Estuaries

These are These are found where found where sand bars sand bars and barrier and barrier islands islands form.form.

Bar-Built EstuariesBar-Built Estuaries The shallow The shallow

water behind water behind these barrier these barrier islands forms islands forms low salinity low salinity estuaries.estuaries.

Tectonic EstuariesTectonic Estuaries

These These estuaries estuaries form where form where land sank or land sank or subsided.subsided.

Tectonic EstuariesTectonic Estuaries

A good A good example of example of this type of this type of estuary is estuary is San Francisco San Francisco Bay.Bay.

Do you know the Do you know the name of the last type name of the last type

of estuary?of estuary?

Think Ice!Think Ice!

Fjords!Fjords! Fjords were Fjords were

created when created when retreating retreating glaciers cut glaciers cut deep in the deep in the earth.earth.

Fjords!Fjords!

Where in Where in the United the United States States might we might we find fjords?find fjords?

Facts About The Chesapeake Facts About The Chesapeake BayBay

The Chesapeake Bay is the The Chesapeake Bay is the largest estuary in the United largest estuary in the United

States.States.

The bay is shallow. Can you The bay is shallow. Can you guess its average depth?guess its average depth?

106 ft.106 ft. 56 ft56 ft 32 ft.32 ft. 21 ft.21 ft. 14ft. 14ft. 9ft.9ft.

THE ANSWER!THE ANSWER!

21 feet is the correct 21 feet is the correct answer. The deepest spot answer. The deepest spot in the bay is 174 feet near in the bay is 174 feet near Annapolis Md.Annapolis Md.

A watershed is the A watershed is the drainage area for the drainage area for the

bay.bay.Can you name the 6 Can you name the 6 states that make up the states that make up the watershed of the watershed of the Chesapeake Bay?Chesapeake Bay?

VirginiaVirginiaMarylandMarylandWest VirginiaWest VirginiaDelawareDelawareNew YorkNew YorkPennsylvaniaPennsylvania

Can you name the 5 major Can you name the 5 major rivers that flow into the rivers that flow into the

bay?bay? From South to From South to NorthNorth

JamesJames YorkYork RappahannockRappahannock PotomacPotomac SusquehannaSusquehanna

Which of those 5 rivers Which of those 5 rivers contributes the most fresh contributes the most fresh

water to the bay?water to the bay? The Susquehanna River The Susquehanna River

provides about 50% of the fresh provides about 50% of the fresh water coming into the Bay.water coming into the Bay.

The river empties an average of The river empties an average of 19 million gallons of water per 19 million gallons of water per minute.minute.

Can you name a mammal Can you name a mammal that is named after the Bay?that is named after the Bay?

Think you Think you know?know?

The The Chesapeake Chesapeake Bay Bay RetrieverRetriever

The Bay area is home to The Bay area is home to over 15,000,000 people!over 15,000,000 people!

About About 50,000 50,000 commercial commercial vessels enter vessels enter the Bay each the Bay each year.year.

The Bay area is home to The Bay area is home to over 15,000,000 people!over 15,000,000 people!

All these All these people and people and activities activities put a strain put a strain on the Bay on the Bay ecology. ecology.

Bay OrganismsBay Organisms

The Bay is home to over The Bay is home to over 3600 living organisms!3600 living organisms!

Marsh DwellersMarsh Dwellers Marsh dwellers Marsh dwellers

are located in are located in and around and around marshes. They marshes. They include small include small fish, birds, and fish, birds, and marsh grasses.marsh grasses.

SAV CommunitiesSAV Communities Submerged Submerged

Aquatic Aquatic Vegetation Vegetation Communities Communities are important are important for many for many reasons. They reasons. They include ducks, include ducks, crabs, and crabs, and eelgrass.eelgrass.

Plankton CommunityPlankton Community

The The plankton plankton community community includes the includes the drifters drifters of of the Bay. the Bay.

Plankton CommunityPlankton Community

It includes It includes phytoplanktophytoplankton, bacteria, n, bacteria, and and zooplankton.zooplankton.

Benthic CommunitiesBenthic Communities Benthic refers Benthic refers

to the bottom to the bottom of the Bay. of the Bay. Benthic Benthic organisms organisms include include oysters, clams, oysters, clams, barnacles, and barnacles, and mud crabs.mud crabs.

Nekton CommunitiesNekton Communities

Nekton Nekton refers to the refers to the swimmers swimmers of the Bay.of the Bay.

Nekton CommunitiesNekton Communities Croaker, Croaker,

Spot, and Spot, and menhaden menhaden use shallow use shallow water in the water in the Bay as a Bay as a nurserynursery