Pacific Reef Heron
Egretta sacra
Pacific reef herons are medium-sized herons, reaching 57 to 66 cm (22 to 26 in) in length. They have a wingspan of between 90 and 110 cm (35 and 43 in) and reach an average weight of 400 g (14 oz). The species displays an unusual, non-sexual dimorphism, with some members having entirely white plumage ('light' morph) and others (the larger portion) being charcoal-grey ('dark' morph). The reason for the colour variation or "morph", is unknown, though it is most commonly thought to be related to camouflage. The plumage of immature herons tends to be browner and duller in colour.
ID text from Wikipedia, CC BY-SA 4.0
White-faced Heron
Egretta novaehollandiae
The adult white-faced heron is medium-sized for the family and mostly pale blue-grey. The forehead, crown, chin and upper throat are white. The crown pattern is variable, with the white occasionally spreading down the neck; the variability makes identification of individuals possible. The iris may be grey, green, dull yellow or cinnamon. The regions between the eye and bill on the side of the head (lores) are black. The beak is black and often pale grey at the base. Voice: The most common call of the white-faced heron is a gravelly croak or gobble, graak or graaw and is typically given in flight, in interactions or in aggressive encounters. Another call, gow, gow, gow is typically given upon returning to a nest. High pitched wrank, oooooooooh or aaarrrgh calls are given as alarm calls.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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