Bay Facts
The Bay is full of interesting facts and trivia related to its history, wildlife, geography and more.
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 moreWhat 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.
1.6 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 moreBald 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 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.
18 trillion gallons
The Chesapeake Bay holds more than 18 trillion gallons of water.
Getting oxygen underwater
Just like those on land, animals in the Chesapeake Bay need oxygen to survive. Oxygen is present underwater in dissolved form, and in order to thrive, animals like blue crabs need dissolved oxygen concentrations of three milligrams per liter.
Learn moreOne million waterfowl
Nearly one million waterfowl winter on the Bay–approximately one-third of the Atlantic coast’s migratory population. The birds stop to feed and rest on the Bay during their annual migration along the Atlantic Migratory Bird Flyway.
Learn more34 degrees Fahrenheit
Water temperatures in the Bay fluctuate widely throughout the year, dropping as low as 34 degrees in winter.
1,800 local governments
There are nearly 1,800 local governments in the Bay watershed, including towns, cities, counties and townships.
Nearly 50 thousand miles of rivers, streams and creeks in one watershed
The Susquehanna River watershed includes nearly 50 thousand miles of rivers, streams and creeks.
What is a shallop?
Captain John Smith and his men sailed the Chesapeake Bay in a modest wooden boat called a shallop–an open wooden workboat such as a barge, dory, or rowboat that was small enough to row but also had one or two sails.
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.
35 miles wide
The widest point of the Chesapeake Bay measures 35 miles, and is located near the mouth of the Potomac River.
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.
Volunteering with environmental organizations
While one-third of watershed residents have volunteered their time or donated their money to a charitable organization, less than two in ten volunteers have done so for an environmental organization.
500,000 Canada geese
More than 500,000 Canada geese winter in and near the Bay.
Learn moreThe 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 more1,800 sunken vessels
More than 1,800 vessels have met their end in Bay waters, lying broken and battered on the Bay's floor.
Can we do more?
Seventy percent of watershed residents want to do more to help make their local creeks, rivers and lakes healthier.
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 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.
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.
Majority of striped bass spawn in the Bay
Seventy to ninety percent of all striped bass, known locally as rockfish, were spawned in the Bay.
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