Kate Poole stands over the carcass of the whale. (Brian Higgins/CBC)

Officials in Prince Edward Island say a whale discovered on P.E.I.'s north shore Wednesday morning had been dead for a while.

Environment officials and staff from the Atlantic Veterinary College are now investigating how the seven-metre Minke whale died.

Kate Poole of Goose River made the discovery on her morning beach walk, east of St. Peters.

Poole told CBC News she saw the whale half on the sand and half in the water.

"I couldn't really tell when I first seen it whether it was still alive or not, cause there is sort of a protrusion from its mouth that's moving in and out," she said.

"I came back up to the house, and we were thinking, you know, are we going to throw buckets of water on it or try and push it out or whatever. So we went back down and really, when we took a real good look, it's like no, this whale is no longer with us."

Environment officials said the whale was an adult female and judging from the state of decomposition, had been dead for some time. They said they are concerned by deep cuts on the mammal's tail that suggest it could have been entangled in ropes.

Minke whales are frequent visitors to the gulf.

Officials said high winds and waves on Tuesday likely pushed the carcass onto the beach.

They hope to dissect the animal and collect tissue samples in the next few days.

That may reveal clues about how the animal died and its health leading up to its death.