Bay Facts
The Bay is full of interesting facts and trivia related to its history, wildlife, geography and more.
80% of the Bay's freshwater
Collectively, the Chesapeake’s three largest rivers—the Susquehanna, Potomac and James Rivers—provide more than 80% of the fresh water to the Bay.
Saltiest part of the Bay
Salinity is highest at the mouth of the Chesapeake Bay, where water from the Atlantic Ocean enters.
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.
12 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.
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.
9.6 million acres of land
Approximately 9.6 million acres of land in the Bay watershed have been permanently protected from development by Bay Program partners.
Learn more1,800 local governments
There are nearly 1,800 local governments in the Bay watershed, including towns, cities, counties and townships.
500 million pounds of seafood
The Bay produces about 500 million pounds of seafood per year.
64,000 square miles
The area of the watershed is about 64,000 square miles.
Longest river fully within Maryland
The 110-mile-long Patuxent River is the longest river to flow exclusively within the borders of Maryland.
84 degrees Fahrenheit
Water temperatures in the Bay fluctuate widely throughout the year, reaching as high as 84 degrees in summer.
500,000 Canada geese
More than 500,000 Canada geese winter in and near the Bay.
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 moreThe 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.
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.
First recorded European to enter the Bay
In 1524, Italian Captain Giovanni da Verrazano became the first recorded European to enter the Chesapeake Bay.
26 different SAV species
The Chesapeake Bay is home to 26 different species of submersed aquatic vegetation (SAV), including freshwater plants, estuarine plants, redhead grass, and marine species.
Formally recognized tribes in Maryland
The State of Maryland has formally recognized three tribes: the Piscataway Indian Nation, Piscataway Conoy Tribe and the Accohannock Indian Tribe.
Learn more10,000 years old
The Chesapeake Bay was formed about 10,000 years ago when glaciers melted and flooded the Susquehanna River valley.
51 billion gallons
Approximately 51 billion gallons of water flow into the Bay each day from its freshwater tributaries.
Learn more6,282,718 acres of greenspace
There are 6,282,718 acres of accessible green space within the Chesapeake Bay watershed.
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).
100,000 smaller tributaries
The Chesapeake Bay watershed has 150 major rivers and streams, but contains more than 100,000 smaller tributaries.