In January, trout and eels died en masse in an event thought to be linked to low levels of dissolved oxygen in the lake's surface water.
"I went up yesterday and saw about 20 dead or dying eels," environmental scientist Andy Hicks said.

"The dead eels are very obvious to any visitors who approach the shore, with dead or dying fish observed around the boat ramp, camping grounds and northern end of the lake.

"There was a slight stink in the air."