What happened
In August 1817, a huge, serpentine animal began to be seen in Gloucester Harbor on Cape Ann; for several weeks it swam in the bay, often close to shore and in broad daylight. Witnesses – fishermen, sailors, merchants and officials – estimated its length at anywhere from a dozen or so to several dozen meters and described a dark back with a row of humps and a head resembling that of a turtle or snake, held above the water. People shot at it and tried to catch it in nets, and the crew of the schooner “Caravan” reportedly even fired a cannon at it. The Linnaean Society of New England in Boston appointed a committee that questioned witnesses and recorded their sworn statements. Sightings recurred in the following years off the coast of Massachusetts.
Witnesses
Numerous Gloucester residents, including fishermen, sailors and officials; some of them gave statements before the Linnaean Society committee.
Explanations and hypotheses
When, soon afterward, a small, deformed snake was killed on shore, the committee declared it a juvenile of a new species and named it Scoliophis atlanticus – which quickly made its findings a laughingstock, since it turned out to be an ordinary land snake with a curved spine. Proposed explanations for the sightings include porpoises or dolphins swimming in single file, large fish and whales, and Joe Nickell suggested a narwhal. The number and credibility of the witnesses mean that the case has no single convincing explanation.
Unexplained There is no convincing explanation.
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