WA shark activist's boat impounded

An animal activist protesting Western Australia's controversial shark kill policy has caused a boat and trailer to be impounded by police.

Marine Rescue Unit campaign co-ordinator Simon Peterffy, who made international headlines in 2012 when he boarded a Japanese whaling vessel, was reportedly preparing to take footage of the latest shark killing on Friday morning when he was given a move on notice.

A police spokeswoman said the boat was seized because the people in possession of it could not identify the owner.

"The trailer was seized on the basis that it was unregistered and the affixed license plate may not be consistent with the trailer," she said.

Police seized both to conduct further inquiries and the boat owner, who is not Mr Peterffy, has since been identified and will collect the vessel.

Meanwhile, the fisherman contracted to set and monitor drum lines in the state's southwest region has killed a large shark and taken the carcass out to sea.

The animal was caught off Meelup Beach, where the first shark was caught and killed on Australia Day under the new policy.

The number of sharks caught and killed off WA beaches so far is unclear.