After a tense few seconds, the pair realised ‘‘the long white shape’’ almost as long as their boat was the underbelly of a shark that had already been caught and killed.

The two men hooked the monster fish with an anchor before dragging it to shore.

Mr Oliver, of Cooks Hill, said once on dry land the pair took a close look at the creature they believed had been caught on Saturday during a fishing competition held by the Lake Macquarie Game Fishing Club.

‘‘We went out on Sunday morning about 7am and were fishing on the north-west side of the Swansea Bridge,’’ he said.

‘‘We just spotted this long white shape in the water and realised it was a shark.

‘‘Unfortunately we weren’t the ones who caught it, it had already been caught.’’

Mr Oliver said the shark was possibly caught during the club’s annual tournament, the ‘‘Bigfish Bonanza’’ where about 60 to 70 boats participated.

The shark would have been caught and weighed at the Swansea RSL Club but instead of dumping the carcass out at sea it must have been tossed out at the Swansea Heads, Mr Oliver said.

Further evidence the shark had been weighed was shown in a photograph provided by the two men.

The photograph shows the shark’s stomach protruding from its mouth, a phenomena consistent with a shark being hung upside down while being weighed.

‘‘It would have just been floating around the channel until we spotted it,’’ he said.

‘‘It was a bit of a scary sight for a second. Bryan and I surf a bit so we know sharks are out there but it was strange to see one in the channel.’’

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