According to Matt Lake in Weird Maryland, two perch fishermen, Francis Klarrman and Edward J. Ward, in 1943 spotted something in the water near Baltimore.
“This thing was about 75 yards (69 m) away, at right angles from our boat. At first it looked like something floating on the water. It was black and the part of it that was out of the water seemed about 12 feet (3.7 m) long. It has a head about as big as a football and shaped somewhat like a horse’s head. It turned its head around several times—almost all the way around.”
The first official Chessie sighting was in 1978 and reported to be a grayish figure around 25 feet long and swam with an unusual motion for a normal fish. This sighting was by the mouth of the Potomac River in the bay.
In the summer of 1982, Robert Frew shot a three minute video of Chessie which caused great commotion but it was never proven to be real footage of the supposed monster. The video proved to not have enough visual clarity for anyone to conclude anything from it. A fisherman years later believed he was chasing Chessie with his shotgun but then eventually lost it to the bay.
The last notable sighting of the beast was in 1997, off the shore of Fort Smallwood State Park, very close to shore. The legend of “Chessie” is very similar to, and was likely inspired by, that of “Nessie”, the Loch Ness Monster.
Most sighting reports of this sea monster describe it as a long, snake-like creature. The reported length of the monster varies from 25 to 40 feet (12 m) long. It is said to swim using its body as a sine curve moving through the water.
Manatees occasionally drift north from U.S. tropical waters in the summer months. Many have entered the Chesapeake Bay thus prompting ‘Chessie’ reports.
The Chesapeake Bay is the largest estuary in United States. Its surface and major tributaries cover more than 4,479 square miles (11,600 km2) and in places it is 175 feet (53 m) deep.
To this day, many people of Maryland still believe in the legend of Chessie, but there has been no conclusive evidence to support this phenomena.
Source: Phantoms and Monsters