Te Arawa Lakes Trustt chairman Toby Curtis says the installation of a floating wetland in Lake Rotoehu has provided an unexpected benefit.
Early last year the Rotorua Lakes Strategic Group which includes the Trust, Rotorua District Council and Bay of Plenty Regional Council, launched the manmade wetland in an effort to improve water quality.
It's made up of more than 350,000 plastic soft drink bottles each containing a plant, the roots of which hang in the water.
Mr Curtis says the lake is not only cleaner and clearer, but koura (fresh water crayfish) have taken a liking to the structure. They are hibernating underneath the wetland and clinging to it.
He says fresh water crayfish is regarded as a delicacy, and the trust will investigate whether the wetland could be used to help increase the koura population.