An act of discharging bodily waste through anus (aka taking a dump) by a human on a beach while completely naked.

Etymology: Modern Canadian English; origin Cape Scott, Canada.

The legend has it that once upon a time a fellow from Manchester, UK went camping with some Canadians to Cape Scott in Canada, where the Manchesterite performed a rare ritual of getting naked and discharging supposedly large quantities of bodily waste when waves hit the beach also washing his anus at the same time, while shouting some gibberish that no one understood. Some of his fellow Canadians cheered at the exercise of freedom, while others found it as an act of pollution, together they called this ritual 'pulling a Manchester' due to the the origin of the British fellow.
I saw him pulling a manchester!

Our Manchester-pulled sea is useless for swimming.

I saw remains of a manchester-pull on the beach this morning!
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