In the past four weeks, the lake next to Glenn Johns’ Pemulwuy home has been transformed to look more like a rugby park than a body of water.
An aquatic weed believed to be salvinia molesta, which grew only along the shoreline in January, has multiplied so fast it now covers the entire surface of the water at Lakewood residential community, Pemulwuy.
‘‘It’s just totally covered. It’s just amazing. I would say in the last four weeks it went from 50per cent to 100per cent,’’ Mr Johns said.
‘‘When I first brought it to council’s attention a week ago, they said talk to Stockland. It was about 70per cent covered then and that was last Wednesday, now it’s 100per cent.’’
The plant, considered a weed of national significance by the Department of Primary Industries, should be eradicated on discovery.
Mr Johns said the lake and its surrounds were home to an abundance of wildlife including ducks, pelicans and a pair of black swans, but that birdlife had thinned substantially since the weed coverage increased.
‘‘No exaggeration, there would have been about 300-plus birds two months ago, now we’re down to a couple of dozen, and some species have completely gone. The swans have disappeared.’’
When the Sun visited the site, there were only about 15 ducks and a single egret, with one duckling visibly struggling through the choked waterway.
Mr Johns said if the weed was not cleared immediately, the environmental damage would not just be to birdlife but also to marine life.
‘‘I’ve never seen a fish in the water but we’ve seen eels and small crustaceans. Once you get plant life covering the water, the photosynthesis stops and kills all the marine life, so bottom feeders like crabs or worms can’t survive.’’
A Holroyd Council spokeswoman said as the site’s owner, Stockland was responsible for ensuring the health of the lake.
Stockland development manager John Coffey said the company had engaged a specialist contractor to remove the weed with an aquatic weed harvester from June 16, with the work expected to take about two weeks.
‘‘[The weed] has been caused by the run of unseasonably high temperatures in Sydney over the last three weeks, which has resulted in above-average water temperatures promoting the growth,’’ Mr Coffey said.
He thanked the residents who alerted the company to the problem.