An odd discovery by a fisherman has led to a quick rescue operation conducted by police thanks to a dog who was looking out for her owner.

Around 6 am on Thursday, a German Shepard named Heidi was spotted by a fisherman when she was swimming alongside other items such as a fuel tank, a wetsuit and a tacklebox in Moreton Bay.

According to Queensland Police, Heidi and the items were scooped up and taken to Manly Boat Harbour, where Heidi went to the vet for a checkup.

The Brisbane Water Police were then alerted that a boat may have gotten into trouble as they could not locate the owner of Heidi.

“During the search operation a number of items were located indicating that a boat had gotten into trouble, with rescuers fearing the worst,” Queensland Police said in a statement.

“Finally at around 10.25 am the skipper was spotted clinging to a sunken 4.1-metre vessel near the Brisbane boat passage, Moreton Bay.”

The 63-year-old explained to police that he had run into trouble at sea the night before when the boat lost power.

Heidi treaded water for 11 hours until the fisherman spotted her, while her owner drifted into the Moreton Bay area for almost 15 hours.

The man was taken to hospital, but Queensland Police have explained that Heidi nor her owner were not seriously injured.

“We would take this opportunity to remind boaties to plan for the worst when they’re out on the water,” Senior Sergeant Jay Bairstow from Brisbane Water police said.

“Always wear personal flotation device and ensure that your safety equipment, including EPIRBs, are tested and in good order.”

“Thankfully there was a happy ending to this search and Heidi was able to be our honorary PD for the day.”