A diver works to remove the carcass of a whale impaled on the bow of a cruise ship that docked in Vancouver on Saturday morning. ((CBC))

A team of forensic pathologists will study the corpse of a fin whale found wedged against the bow of a cruise ship in Vancouver on Saturday.

Once the necropsy is complete, the animal will be returned to the ocean.

"These animals, the carcasses are extremely important in terms of the ecosystem of shore, in terms of the continental shelf. They're really islands of life, so we're going to take the animal out quite a ways offshore and deposit the carcass where it should be," said Paul Cottrell, the marine mammal co-ordinator for the Department of Fisheries and Oceans.

The necropsy will determine whether the animal was dead or alive when it collided with the Princess Cruise Lines' Sapphire Princess cruise ship.

Fin whales are the second largest animals in the world after the blue whale. They can reach lengths of up to 30 metres.

The whale found Saturday was roughly 21 metres long and weighed an estimated 70 tonnes.