Australasian Figbird
This bird species have a few races and their colours vary greatly for the males in those races. The female is generally a brownish colour regardless of race and on the day I never got a good photo of one.
Immature birds are duller. You can se here that the young male above still has the plainer brown striped breast of the female but the colour is starting to come through.
The flaviventris race which is found here in Far North Queensland is shown in these photos with its mid yellow belly and general green colour.
The birds as their name would suggest feed on figs but do also use insects and nectar as alternate food sources. I am not sure if the fainter red colour around the eye indicates a younger or older male bird.
The call of the birds is an up and down musical song of squeaky notes.