In the foreground is a male Musk Lorikeet, one of a breeding pair.
This male is somewhat suspicious of the visiting Rainbow, also a male named Elvis who enjoyed accompanying Heather as she went to each aviary with food.
Elvis would jump off her shoulder and make friendly moves to the aviary residents. In this case the male Musky was not too amused although he never actually does anything more than make a few feather ruffling displays at Elvis. Elvis would stay calm and proceed to the next aviary.