A UNIT owner with views over Twin Waters Lake photographed this two-metre shark as it cruised the waterway while anglers watched their lines less than 50 metres away.
But the resident said he wasn't surprised, as the shark was one of several trapped in the lake.
"They say there is an even bigger one, but I haven't seen it myself.
"Once they get into the lakes they get trapped because of the weir.
"They can't get out and then they breed."
Bull sharks, renowned as one of the most vicious shark species, give birth to their young in the upper reaches of rivers and creeks at this time of year.
The lake is an extensive body of water which runs from the Maroochy River to Pacific Paradise.
The photo was taken before recent heavy rain, when the water was unusually clear.
"They're always there but the water isn't usually clear enough to see them," the man said.
"There's always kayaks out there and a lot people fishing.
"During the school holidays, kids swim in there.
"There's no way I'd be jumping in there."
It comes after Noosa Main Beach was evacuated on Saturday after a "large" shark was sighted.
And a "monster" shovelnose shark was caught and released on Fraser Island.
Last year, 43 sharks were caught off Sunshine Coast beaches - an average of one every eight days.
More than 600 have been caught off the Queensland coast every year for the past four financial years.
The number peaked at 716 in 2011-12.
The program caught 667 sharks in 2013-14, including 270 tiger sharks, 101 bull sharks, and 84 black tip sharks.
Seven white pointers were caught.
Bill Gilliland, of the Queensland Seafood Industry Association, said the number of sharks being sighted in south-east Queensland waters at the moment was not out of the ordinary.
But a Queensland Boating and Fisheries spokesman urged swimmers to use caution in local waterways following recent rain.
"The run-off flushes out natural fish stocks from rivers and creeks into estuaries and along our beaches," the spokesman said.
"This provides an ideal environment for feeding sharks.
"This time of year bull sharks give birth to their young in the upper reaches of rivers and creeks and then proceed to coastal areas."
- Don't go into the water after dusk or before dawn.
- Don't swim in murky waters, or near the mouths of estuaries, canals or lakes.
- Don't swim when bleeding or with animals.
- Keep away from schools of fish or areas where fish are being cleaned.
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