With regard to sharks and the Potomac, there’s this bit of trivia:
Shark bite left its mark in Chesapeake history, researchers say
In August of 1640, an English-born laborer stepped off from the sandy shoreline of one of Maryland’s tidal rivers — and into the maw of history. He had only just begun wading in when a “huge fish” sunk its jaws into his thigh and tore away a giant chunk of flesh.
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Flash forward nearly 400 years. A pair of unlikely collaborators — a former federal marine scientist and a physician who moonlights as a history book author — has rescued the account from obscurity to make a bold claim: This was the first documented fatal shark attack in North America. (Read their research paper here.)The 1640 incident predates by two years an attack off what is now New York City, currently listed by the Shark Research Institute as the earliest recorded unprovoked shark attack on the continent. [snip]
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One afternoon that summer — Mountford and Fernicola believe it was August — the overheated laborer decided to swim in the St. Mary’s, a Potomac River tributary just a few miles upstream from the Chesapeake Bay.Per the letter: “Scarcely had he touched the water when a huge fish having suddenly seized the wicked man, before he could retreat to the bank, tore away at a bite, a large portion of his thigh, by the pain of which most merited laceration, the unhappy wretch was in a short time hurried away from the living.”
Copley’s description matches up neatly with a typical bull shark attack, according to Mountford and Fernicola. (Historical accounts often deploy terms such as “huge fish” when referring to sharks, they said.) The blunt-nosed, round-bodied species is known to venture into freshwater. And they often employ a “bump and bite” method with their prey, which appears to be the case here, they said.
It looks improbable but not impossible that a bull shark could swim upriver to DC (bull sharks have been reported as far up the Mississippi as St Louis). But not in January.