The bird is an Intermediate Egret (Ardea intermedia) one of a set of at least 3 'large' white egrets in Australia. I'm pretty certain I have got the name right, but will except corrections!
This bird was feeding in the shallow water outside of the Mamukala Bird Hide when I saw it get the frog. It was caught, turned around and swallowed all in a few seconds.
I hope finally to be back up to speed some - so, thanks in anticipation for comments. Now its your turn to click the blue button and join in with WBW. SM