Warning signs have been put up at Hervey Bay on the Fraser Coast after the reported sighting of two crocodiles.

The council says a kayaker alerted the Department of Environment and Heritage Protection after seeing the crocodiles in Eli Creek on Friday.

Deputy Mayor Trevor McDonald says it is not known if one of the crocodiles may be the same one that was seen last year in the Mary River near Maryborough.

"Given we have the highest tides of the year and a fair amount of run in the water and I believe crocodiles can travel considerable distance I wouldn't either confirm or discount that possibility,' he said.

"I simply do not know.

"Certainly in my 40 years in Hervey Bay this is the first time we've ever reached a point where we have warning signs up."