The infestation of an exotic, noxious weed in a residential Port Douglas lake is creating more havoc than its previous problem of crocodile inhabitation.

The lake at Warri Park, which borders the Ferndale and The Lakes housing estates, has been so choked with the class two weed, Salvinia molesta, that the surface of the water could not be seen, signs adorning the lake’s edge with instructions to not disturb the weed to prevent its spread.

A native weed of Brazil, salvinia occurs naturally in America, Europe and Asia and quickly forms thick mats over water, endangering children and livestock who can become entangled in heavy infestations and creating a haven for mosquitoes.

A declared pest plant and a Weed of National Significance (WONS), it is mainly spread by people who empty aquariums and ponds into waterways, and not only degrades water quality, but causes a four-fold increase in water loss through evaporation.

The parkland surrounding the Ferndale lake was also in such a state of disrepair, that The Newsport contacted both Council and the Department of Primary Industries on Monday morning to find out what was going on.

Early Tuesday morning, an earthmover was digging the weed out of the lake and two CRC staff members were inspecting the weed from a boat launched into the lake, struggling to paddle through the mess.

A large pile of the weed was left barricaded with orange plastic near Port Douglas Road on Wednesday, with passers-by and nearby residents wondering what was going on.  

Cairns Regional Council’s Russell Wild said Council was using an integrated approach to control the infestation, but did not disclose when the lake and parkland would return to its former condition.

“A recent infestation of Salvinia molesta has been found in Ferndale lake, Port Douglas,” he said in a statement.

“A mixture of herbicide, biological, mechanical and containment booms would be used to effectively control the aquatic pest plant,” he said, but did not elaborate.

Co-incidentally, the removal of the weed came as the Asian-Pacific Weed Science Society held its conference in Cairns this week.

With the theme “Weed Management in a Changing World”, delegates from Japan, Korea, the United States and Canada were to discuss ways to reduce the $4 billion annual impact of weeds on agriculture and the environment.