The sea monk, or sometimes monk-fish, was the name given to a sea animal found off the coast of Denmark almost certainly in 1546. At this time it was regarded to be a sea monster and described as a "fish" that looked superficially like a monk. It was mentioned and pictured in the fourth volume of Conrad Gesner's famous Historia Animalium. Gesner also referenced a similar monster found in the Firth of Forth, according to Boethius, and a sighting off the coast of Poland in 1531.
In the early 1850s, Danish zoologist Japetus Steenstrup suggested that the sea-monk was a giant squid, a theory more recently popularised by writer Richard Ellis. Cryptozoologist Bernard Heuvelmans, believed the report was based on the discovery of an errant walrus. More recently, it has been suggested that it was an angel shark Squatina squatina, which is commonly called monkfish in English or munk in Norwegian. Other suggested suspects for the sea monk include a grey seal, a hooded seal, a monk seal, or a Jenny Hanniver.