Richard Du Toit / Red-billed Oxpecker (Buphagus erythrorhynchus) on Burchell's Zebra (Equus burchellii), Mkhuze Game Reserve, KwaZulu-Natal, South Africa

Richard Du Toit / Northern Giraffe (Giraffa camelopardalis) with Red-billed Oxpeckers (Buphagus erythrorhynchus) feeding on parasites in symbiotic relationship, Mkhuze Game Reserve, KwaZulu-Natal, South Africa

Richard Du Toit / Impala (Aepyceros melampus) males fighting, Mkhuze Game Reserve, KwaZulu-Natal, South Africa

Richard Du Toit / Purple-crested Turaco (Tauraco porphyreolophus), Itala Game Reserve, KwaZulu-Natal, South Africa

Richard Du Toit / Northern Giraffe (Giraffa camelopardalis) mother and calf, Itala Game Reserve, KwaZulu-Natal, South Africa

Rob Drummond/ BIA / Pied Oystercatcher (Haematopus longirostris), Victoria, Australia

Rob Drummond / Chestnut Teal (Anas castanea) male, Victoria, Australia

Rob Drummond/ BIA / Black Swan (Cygnus atratus) pair courting, Victoria, Australia

Rob Drummond/ BIA / Eastern Rosella (Platycercus eximius) male, Victoria, Australia

Rob Drummond/ BIA / Australasian Grebe (Tachybaptus novaehollandiae), Victoria, Australia

Rob Drummond/ BIA / Long-billed Corella (Cacatua tenuirostris), Victoria, Australia

Rob Drummond/ BIA / Royal Spoonbill (Platalea regia) wading, Victoria, Australia

Rob Drummond/ BIA / Masked Lapwing (Vanellus miles) wading, Victoria, Australia

Rob Drummond/ BIA / Freckled Duck (Stictonetta naevosa) male, Victoria, Australia

Rob Drummond/ BIA / Freckled Duck (Stictonetta naevosa) male, Victoria, Australia

Rob Drummond/ BIA / Freckled Duck (Stictonetta naevosa) male, Victoria, Australia

Rob Drummond/ BIA / Freckled Duck (Stictonetta naevosa) male, Victoria, Australia

Rob Drummond/ BIA / Pilotbird (Pycnoptilus floccosus), Victoria, Australia

Rob Drummond/ BIA / Hoary-headed Grebe (Poliocephalus poliocephalus), Victoria, Australia

Rob Drummond/ BIA / Hoary-headed Grebe (Poliocephalus poliocephalus), Victoria, Australia

Richard Du Toit / Hippopotamus (Hippopotamus amphibius) mother and calf, Kruger National Park, South Africa

Richard Du Toit / Burchell's Zebra (Equus burchellii) pair, Golden Gate Highlands National Park, South Africa

Richard Du Toit / Impala (Aepyceros melampus) pair drinking at waterhole, Mkhuze Game Reserve, KwaZulu-Natal, South Africa

Richard Du Toit / Burchell's Zebra (Equus burchellii) drinking at waterhole, Mkhuze Game Reserve, KwaZulu-Natal, South Africa

Richard Du Toit / Burchell's Zebra (Equus burchellii) foal running, Mkhuze Game Reserve, KwaZulu-Natal, South Africa

Richard Du Toit / Burchell's Zebra (Equus burchellii) pair, Itala Game Reserve, KwaZulu-Natal, South Africa

Richard Du Toit / Northern Giraffe (Giraffa camelopardalis) calf, Itala Game Reserve, KwaZulu-Natal, South Africa

Richard Du Toit / White Rhinoceros (Ceratotherium simum) mother and calf grazing, Kruger National Park, South Africa

Richard Du Toit / African Elephant (Loxodonta africana) bull browsing, Kruger National Park, South Africa

Rob Drummond/ BIA / Double-banded Plover (Charadrius bicinctus) flapping, Victoria, Australia

Rob Drummond/ BIA / Double-banded Plover (Charadrius bicinctus) on beach, Victoria, Australia

Rob Drummond/ BIA / Spinifex Pigeon (Geophaps plumifera) displaying, Northern Territory, Australia

Rob Drummond/ BIA / Major Mitchell's Cockatoo (Lophochroa leadbeateri) feeding on Gooseberry Cucumber (Cucumis myriocarpus), Northern Territory, Australia

Rob Drummond/ BIA / Black-faced Woodswallow (Artamus cinereus), South Australia, Australia

Rob Drummond/ BIA / Olive-tailed Thrush (Zoothera lunulata), Victoria, Australia

Rob Drummond/ BIA / Brolga (Grus rubicunda) crane, Victoria, Australia

Rob Drummond/ BIA / White-headed Stilt (Himantopus leucocephalus) pair courting, Victoria, Australia

Rob Drummond/ BIA / Red-kneed Dotterel (Erythrogonys cinctus) foraging, Victoria, Australia

Rob Drummond/ BIA / Latham's Snipe (Gallinago hardwickii), Victoria, Australia

Rob Drummond/ BIA / Chestnut Teal (Anas castanea) pair, Victoria, Australia

Rob Drummond/ BIA / White-headed Stilt (Himantopus leucocephalus) wading, Victoria, Australia

Rob Drummond/ BIA / Whiskered Tern (Chlidonias hybrida) flying, Victoria, Australia

Rob Drummond/ BIA / Black-fronted Dotterel (Elseyornis melanops), Victoria, Australia

Rob Drummond/ BIA / Australian Crake (Porzana fluminea) foraging, Victoria, Australia

Rob Drummond/ BIA / Baillon's Crake (Porzana pusilla) foraging, Victoria, Australia

Rob Drummond/ BIA / Brush Bronzewing (Phaps elegans) male, Victoria, Australia

Rob Drummond/ BIA / Pink Robin (Petroica rodinogaster) male, Victoria, Australia

Rob Drummond/ BIA / Yellow Robin (Eopsaltria australis), Victoria, Australia