UPDATE
A spokeswoman for Roads and Maritime said they were working with police and National Parks and Wildlife Service on the matter.
“A range of offences under both the marine and other legislation may apply in these circumstances,” she said.
“Roads and Maritime will ensure that appropriate action is taken.
“If anyone has information they can contact Roads and Maritime on 13 12 36.”
UPDATE
A volunteer for animal rescue group WIRES said she was “speechless and close to tears” when she saw the destruction of the Ospreys’ nest in the Georges River.
National Parks and Wildlife Service contacted Toni Burnham on Sunday morning and asked if she could go to the nest.
She collected some twigs and other leaf matter from around her Bundeena home and drove to Sans Souci where water police were waiting.
”My first instinct was to salvage what remained of the nest, and hopefully save one chick I was led to believe was still there,” she said.
”But, when we arrived, we found there was really nothing left of the nest.
“It was just five or six twigs on the little platform which I believe is used for maintenance purposes.
”I was speechless and close to tears.
“I often deal with distressing situations, but this really saddened me.
“To the Ospreys, it probably looked like an awesome place to build a nest – out in the water, away from houses…
“I looked in the water, but it was probably futile.”
Ms Burnham believes they were probably only about an hour and a half late to save at least one chick.
She urged anyone who saw wildlife in distress or in danger to call WIRES on 1300 094 737.
“You can also call police or National Parks and Wildlife Service and they will contact us,” she said.
EARLIER
Jet-ski “hoons” have deliberately destroyed the nest of a pair of rare and endangered Eastern Ospreys on a channel marker in the Georges River.
The chicks were believed drowned. The birds usually incubate two to four eggs.
The Georges River Wildlife Facebook page said the “deliberate, cruel destruction” of the nest, began on Friday and continued on the weekend.
Authorities were alerted, but were too late to stop the nest being destroyed.
Over several days, the jet-skiers returned deliberately swamping the nest in waves of water while the parent birds desperately tried to rebuild it.
Just a month ago, National Parks and Wildlife Service [NPWS] reported the nest was “great news for the species as they are not known to breed this far south and may indicate they are repopulating a greater area of their range”.
NPWS tried to protect the nest by not revealing it was in the river, saying it was “near Georges River”.
A post on the Georges River Wildlife Facebook page on Sunday, read: “It really has been a sad experience both Friday and this morning watching people have fun destroying the Osprey nest and even more so watching the male start nest building efforts again”.
“He seemed obviously exhausted, struggling to break off much smaller branches than what I have seen previously,” she said.
“During most of the nest construction it was winter with much less traffic on the water.
“So, today when he does find a branch and break it off, he usually has to circle around before being able to deliver it to the nest.”
“Whether there were eggs or chicks in the nest, I do not know but whatever was there is floating down the river.
“I suspect the female knows all is lost as she left the nest (not scared off, just left) about 8.10am and had not returned around 12.20pm when I headed home.
“Recently, she only leaves for around 30 minutes to eat then returns, nudging the male off the nest.”
The post said Water Police had visited the site and taken photos.
In September, NPWS regional manager Gary Dunnett said the sighting was “great news for the species as they are not known to breed this far south and may indicate they are repopulating a greater area of their range”
“The Eastern Osprey is quite magnificent to see in flight but despite a wingspan of up to 1.7 metres, they are still much smaller than the White bellied sea eagle," he said.
“The species is uncommon to rare or absent from closely settled parts of south-eastern Australia so for this part of Sydney to have a breeding pair in the area is really very special.
“The fact that an apex predator such as Ospreys are nesting is also a great sign about the environmental health of the Georges River system.
“These birds favour coastal areas where they hunt for fish to feed their growing brood.
“It was not possible to see the number of chicks these birds are tending but they usually incubate 2-4 eggs.
“I am looking forward to seeing the chicks fledge in a month or so and hope they too stay in the area when they fly the nest.”