A juvenile Brown Goshawk in flight.
Having sighted Swamp Harriers at the Werribee Treatment Plant on many occasions, I failed to apply sufficient rigour to correctly identify this bird and I put it up on Bushpea as a female Swamp Harrier.
My thanks to Ákos Lumnitzer, a nature photographer of Sydney, who noticed my mistake and took the trouble to contact me about it.
Ákos suggested the bird may possibly be a juvenile Brown Goshawk, and having checked it out further, I agree with him. A similar candidate is juvenile Collared Sparrowhawk, but Swamp Harrier, it is not.