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 more35.5 million years
The formation of the Chesapeake Bay happened 35.5 million years ago when a meteor collided with Earth, forming a massive crater.
Chesapeake National Recreation Area
Legislation proposed by Maryland’s Senator Chris Van Hollen and Representative John Sarbanes to incorporate the bay into the nation’s park system.
4,863 feet above sea level
At 4,863 feet above sea level, Spruce Knob is the highest point in the Chesapeake watershed.
Largest estuary in the United States
The Chesapeake Bay is an estuary: a body of water where fresh and salt water mix. It is the largest of more than 100 estuaries in the United States and third largest in the world.
Learn more18 trillion gallons
The Chesapeake Bay holds more than 18 trillion gallons of water.
The 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).
The Chesapeake Bay's first inhabitants
The first inhabitants of the Chesapeake Bay region are referred to as Paleo-Indians. They came more than 10,000 years ago from other parts of North America, drawn in by the abundance of wildlife and waterways.
Learn moreRemnants of an ancient river
A few deep troughs run along much of the Bay’s length and are believed to be remnants of the ancient Susquehanna River.
How we can fix water pollution
Eighty-six percent of watershed residents believe if people work together, water pollution can be fixed.
Meaning of "Chesepiooc"
The word Chesepiooc is an Algonquian word referring to a village "at a big river." In 2005, Algonquian historian Blair Rudes helped dispel the widely-held belief that the name meant “great shellfish bay.”
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.
100,000 smaller tributaries
The Chesapeake Bay watershed has 150 major rivers and streams, but contains more than 100,000 smaller tributaries.
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.
29 species of waterfowl
The Chesapeake region is home to at least 29 species of waterfowl.
Learn more10,000 years old
The Chesapeake Bay was formed about 10,000 years ago when glaciers melted and flooded the Susquehanna River valley.
60% of Chesapeake forests
Sixty percent of Chesapeake forests have been divided into disconnected fragments by roads, homes and other gaps that are too wide or dangerous for wildlife to cross.
Learn more1,300 access sites
There are more than 1,300 public access sites on the Chesapeake Bay and its tributaries.
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 more4-30 mile width
The Bay’s width ranges from four miles near Aberdeen, Maryland, to 30 miles near cape Charles, Virginia.
More than 200 historic shipwrecks
Mallows Bay is the final resting place for more than 200 historic shipwrecks dating back to the Revolutionary War. Commonly referred to as the “Ghost Fleet” of Mallows Bay, it is the largest collection of shipwrecks in the Western Hemisphere.
What is brackish water?
Most of the water in the Bay, including in the middle portion of the Bay and its tidal rivers, is brackish–a mixture of salty and fresh, with a salinity level of greater than 0.5 ppt but less than 25 ppt.
500,000 Canada geese
More than 500,000 Canada geese winter in and near the Bay.
Learn moreReplacing grass lawn with native plants
Twenty-six percent of watershed residents have replaced an area of their grass lawn with native plants. Native plants provide food and habitat to bees, birds and butterflies, and often don’t need to be watered or fertilized.
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