Dog owners are being urged to keep control of their pets after a swan was mauled at a park in Secret Harbour.
Horrified onlookers watched as the unleashed dog chased the mother swan off its nest at Lagoon Park near the Secret Harbour beach on Monday afternoon.
One witness said the dog then chased the swan into the lake before dragging it by the neck back to shore.
Wildlife rescue group, River Wren Rescue, were called to take the remaining male swan and six eggs into care.
River Wren Rescue founder Selina Thompson said the mother swan suffered severe injuries and would never have survived the attack.
"Her wings were nearly completely torn off of her body and she had broken bones all over the place," Ms Thompson said.
"Even if she didn't pass she would've had to be euthanised."
Ms Thompson said the eggs are being incubated and the other swan is recovering well after suffering shock.
She is urging dog owners to be responsible for their pets.
"If you know that your dog is one that does like a chase, they should be on a lead," Ms Thompson said.
"If you can't control your animal then you shouldn't be taking it off its lead."
City of Rockingham Mayor Barry Sammels said they are aware of the alleged attack but are not investigating as they have not received a formal complaint.
"Whenever a dog attack takes place witnesses are encouraged to contact the City as soon as possible so the necessary investigations can be carried out," Mayor Sammels said.
"The City can issue an infringement notice of $400 for a dog attack, while the maximum enforceable penalty in a court of law is up to $10,000 or $20,000 if the dog involved was previously declared dangerous or is a restricted breed."
If you would like to donate to River Wren Rescue click here.

The swans have lived and raised a number of young at The Lagoon for several years. PIC: Feebee Jan Bain/Facebook
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