Not far from Bigge Island was, for me, one of the highlights of the Kimberley trip, Sterna Island. If you click on the photo it will fill your screen and you can try your diagnostic skills. There are three species of Tern to be found. If you find a fourth let me know. The back arrow in your browser brings you back to this page.
There were many thousands of breeding pairs of terns. Plus a pair of Peregrines that could have lunch whenever they wanted and one did before our very eyes. A White-bellied Sea Eagle also flew through causing a fair bit of mayhem. But it was mostly about the terns. The Roseate were in peak breeding plumage …
The presentation of a fish serves the same purpose as a rose on Valentines day.
The next photo shows Crested and Lesser Crested Terns in the one view. To tell them apart just remember the Crested has a bill the colour of Lemon peel, the Lesser Crested has a bill the colour of Orange peel …
Birds just bursting with energy. You have to click on this one …
bobmcgee 
Terns have always been difficult for me to identify. Those photos are useful and rather good.