Michael Pitts / Saltwater crocodile underwater {Crocodylus porosus} Kakadu NP, NT, Australia

Steven David Miller / A Perentie (Varanus giganteus) using its forked tongue to detect smells, Alice Springs Reptile Centre, Northern Territory, Australia, Captive. May.

Steven David Miller / Red-collared lorikeet (Trichoglossus rubritorquis) pair examining hole in Eucalyptus as a potential nesting hollow. Katherine, Northern Territory, Australia.

Paul Williams / Budgerigars (Melopsittacus undulatus) flocking to find water, Northern Territory, Australia

Ingo Arndt / Cathedral Termite mount, Litchfield National Park, Northern Territory, Australia

Ingo Arndt / Magnetic termite (Amitermes meridionalis) aerial view of mounds in grassland, Litchfield National Park, Northern Territory, Australia.

Ingo Arndt / Magnetic termite (Amitermes meridionalis) aerial view of mounds in grassland, Litchfield National Park, Northern Territory, Australia.

Ingo Arndt / Magnetic Termite (Amitermes meridionalis) mounds in grassland, Litchfield National Park, Northern Territory, Australia.

Ingo Arndt / Green tree ant (Oecophylla smaragdina) group on entrance from nest, built from woven leaves, Northern Territory, Kakadu National Park, Australia.

Ingo Arndt / Intermediate Egret (Egretta intermedia) Kakadu National Park, Northern Territory, Australia, December

Ingo Arndt / Aboriginal Rock Art / depicting human figure / Anbangbang Gallery / Nourlangie Range / Kakadu National Park, Northern Territory, Australia

Ingo Arndt / Floodplain with Pandanus palms under storm clouds, Kakadu National Park, Northern Territory, Australia, December 2010