Marine Rescue Rockingham have issued a warning to skippers after a yacht ran aground off Shoalwater.
The crew were rescued from the yacht, which ran aground on Shag Rock, between Seal Island and Penguin Island, on Wednesday afternoon.
The damaged yacht has since broken up overnight and debris is floating around Seal Island and inshore along Shoalwater Marine National Park.
"Much of this debris are large jarrah sections not easily visible, and presents a risk to vessels or watercraft operating around Seal / Penguin Islands or the Shoalwater Coast," Marine Rescue Rockingham's Facebook read.

Yacht debris off Shoalwater. PIC: Marine Rescue Rockingham
Locals are also concerned about a fuel and oil spill coming from the yacht.
"This spill is within a few hundred metres of the breeding/feeding ground of the critically endangered Little Penguin, the breeding ground for pelicans, the migrating bridled terns who fly all this way to breed on these few islands, the Sea lions the marine life is endless out there and all will be affected if they come in contact with any of the leaking contaminants," Hands Off Point Peron Facebook group said.
It is not known when the yacht will be recovered.

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