Bay Facts
The Bay is full of interesting facts and trivia related to its history, wildlife, geography and more.
3,600 species of plants and animals
The Bay supports more than 3,600 species of plants and animals, including 348 species of finfish, 173 species of shellfish, over 2,700 plant species and more than 16 species of underwater grasses.
Learn moreThe Bay's largest tributary
The Susquehanna River is the Bay’s largest tributary, and contributes about half of the Bay’s freshwater (about 19 million gallons per minute).
How we can fix water pollution
Eighty-six percent of watershed residents believe if people work together, water pollution can be fixed.
10,000 years old
The Chesapeake Bay was formed about 10,000 years ago when glaciers melted and flooded the Susquehanna River valley.
21 feet deep
The Bay is surprisingly shallow. Its average depth, including all tidal tributaries, is about 21 feet. A person who is six feet tall could wade through more than 700,000 acres of the Bay and never get his or her hat wet.
Longest river fully within Maryland
The 110-mile-long Patuxent River is the longest river to flow exclusively within the borders of Maryland.
Longest free flowing river in the Bay watershed
The 195-mile-long Rappahannock River is the longest free flowing river in the Chesapeake Bay watershed.
6,282,718 acres of greenspace
There are 6,282,718 acres of accessible green space within the Chesapeake Bay watershed.
Where does the Bay get its water?
The Bay receives about half its water volume from the Atlantic Ocean in the form of saltwater. The other half (freshwater) drains into the Bay from the enormous 64,000-square-mile watershed.
80,000 acres of underwater grasses
Nearly 80,000 acres of underwater grasses grow in the shallows of the Chesapeake Bay and its tributaries. Young and molting blue crabs rely on underwater grass beds for protection from predators.
Learn moreCan we do more?
Seventy percent of watershed residents want to do more to help make their local creeks, rivers and lakes healthier.
Learn more1.6 billion pounds of blue crabs
Since 1990, commercial watermen have harvested more than 1.6 billion pounds of blue crabs from the Bay. Data show commercial harvest has experienced a steady decline, and in 2014 hit the lowest level recorded in 25 years: 35 million pounds.
Learn moreCaptain John Smith visits the Bay
In 1608, Captain John Smith set off on the first of two voyages where he charted the land and waterways, and later drew an elaborate and remarkably accurate map of the Chesapeake Bay.
Learn more4,480 square miles of surface area
The surface area of the Bay and its tidal tributaries is approximately 4,480 square miles.
Bald eagle recovery in the Chesapeake
In the 1970’s, there were as few as 60 breeding pairs of bald eagles in the entire Bay region. Today, as much as 3,000 breeding pairs of bald eagles can be found.
Learn more12 species of shark
There are twelve known species of shark that have been sighted in the Chesapeake Bay, with only five considered a common occurrence—smooth dogfish, sand tiger shark, sandbar shark, spiny dogfish, and bull shark.
29 species of waterfowl
The Chesapeake region is home to at least 29 species of waterfowl.
Learn more200 miles long
The Bay itself is about 200 miles long, stretching from Havre de Grace, Maryland, to Virginia Beach, Virginia.
84 degrees Fahrenheit
Water temperatures in the Bay fluctuate widely throughout the year, reaching as high as 84 degrees in summer.
The Powhatan tribes
There were many different tribes in the region before Europeans arrived, but the dominant group were Algonquian speakers known collectively as the Powhatan tribes.
Largest land-to-water ratio in the world
The Chesapeake Bay’s land-to-water ratio is 14:1: the largest of any coastal water body in the world. This is why our actions on land have such a big impact on the Bay’s health.
12 major rivers
Major rivers emptying into the Bay include the James, York, Rappahannock, Potomac, Patuxent, Patapsco and Susquehanna from the west and the Pocomoke, Wicomico, Nanticoke, Choptank and Chester from the east.
35.5 million years
The formation of the Chesapeake Bay happened 35.5 million years ago when a meteor collided with Earth, forming a massive crater.
200 invasive species
There are as many as 200 invasive species present in the Chesapeake Bay watershed that are causing some serious issues in an already-stressed ecosystem. Some examples include blue catfish, snakehead, zebra mussel, purple loosestrife, and nutria.