Oyster Harvests in the Chesapeake Bay

A River And an Ocean What Is an Estuary? A meeting place between:

The Chesapeake Bay Largest of 130 estuaries in the U.S. 18,000,000,000,000 gallons of water 3600 species of plants and animals 500,000,000 pounds of seafood every year

The Chesapeake Bay A diverse habitat: Water Marsh Mud

When a River Meets the Sea, What Are the 2 Main Water Properties that are Affected? –Temperature –Salinity Both of these affect the DENSITY of the water

First, Let’s Look at Density What is DENSITY? Density describes how tightly packed the molecules in a substance are What would happen to the density if salt was added? Adding salt ____________ the density of the solution. INCREASES

When River Water and Ocean Water Meet They may mix together They may form layers They may do some of both

What Will Happen if Salt Water is Added to Fresh Water? Will they mix together? Will they form layers? What is your prediction? SALT FRESH

Salinity Plays an Important Role in Estuarine Circulation As river water and ocean water meet, how do they interact? River Ocean

Salinity Plays an Important Role in Estuarine Circulation The Chesapeake Bay is a partially mixed estuary. River Ocean

HOW IS SALINITY IMPORTANT TO WATER CIRCULATION IN THE BAY? FRESH SALT

How Do We Measure Salinity? We can use a HYDROMETER to measure density Which cylinder contains the salt water? Remember, as salt is added to water, density will increase. HYDROMETER

How Do We Measure Salinity? We can use the refraction of light to measure salinity. This works because light bends as it goes through different densities The saltier the water, the denser the water and the more the light bends

How to Use a Refractometer

These Water Samples Were Taken from Different Depths in the Bay, Can You Match the Depth with the Sample? SAMPLE #1: 0 o /oo SAMPLE #2: 35 o /oo SAMPLE #3: 20 o /oo Depth of water sample Salinity of water sample 1 meter (surface) 5 meters 10 meters

These Water Samples Were Taken from Different Depths in the Bay, Can You Match the Depth with the Sample? Depth of water sample Salinity of water sample 1 meter (surface) Sample 1: 0 o /oo 5 meters 10 meters

These Water Samples Were Taken from Different Depths in the Bay, Can You Match the Depth with the Sample? Depth of water sample Salinity of water sample 1 meter (surface) Sample 1: 0 o /oo 5 metersSample 3: 20 o /oo 10 meters

These Water Samples Were Taken from Different Depths in the Bay, Can You Match the Depth with the Sample? Depth of water sample Salinity of water sample 1 meter (surface) Sample 1: 0 o /oo 5 metersSample 3: 20 o /oo 10 metersSample 2: 35 o /oo

What Happens to the Salinity in the Chesapeake Bay as the Water Gets Closer to the Ocean?

Can You Match the Water Sample to the Part of the Bay It Came From? 0 o /oo 15 o /oo 30 o /oo Site A Site B Site C

Can You Match the Water Sample to the Part of the Bay It Came From? Site A 0 0 /oo Site B 15 0 /oo Site C 30 0 /oo

How Does Temperature Affect Density? As temperature increases, the speed of the water molecules increases. Does the density of the water increase or decrease as the molecules move faster?

How Does Temperature Affect Density? As temperature INCREASES density DECREASES

Think About a Hot Air Balloon! The air inside is warmer than the air outside, so the density is lower inside than outside So the balloon will rise to the top!

Can You Predict What Will Happen When Cold Water Is Added to Hot Water? Make your prediction and then watch the demo. Would the order that the water is added matter? COLD HOT

In the Chesapeake Bay, Where Would You Expect Water to Be Warmest? At the top? Or at the bottom?

As the Seasons Change, the Temperatures of the Water Change As the water warms up in summer time, will the water at the surface stay there or sink?

As the Seasons Change, the Temperatures of the Water Change As the warm water begins to cool down in the Fall, will the water at the surface stay there or sink?

How Does Salinity Affect the Organisms that Live in the Chesapeake Bay? Cut out the 6 Chesapeake Bay Organisms Paste each on the map of the Chesapeake Bay where they can find the salinity level needed to survive.

CROAKER ANCHOVY BLUE CRAB SILVERSIDE SEATROUT SHAD

Why Are Temperature and Salinity Important to the Different Organisms in the Chesapeake Bay?

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