Juergen Freund / Wildlife carer Margit Cianelli with juvenile Lumholtz kangaroo (Dendrolagus lumholtzi) with radio collar. The tree kangaroo has a radio collar to allow her to explore her forest surroundings ready for...

Juergen Freund / Margit Cianelli wildlife carer with young Lumholtz kangaroos (Dendrolagus lumholtzi), one with a radio collar. The tree kangaroo has a radio collar to allow her to explore her forest surroundings read...

Juergen Freund / Wildlife carer Margit Cianelli with young year old Lumholtz tree kangaroo (Dendrolagus lumholtzi) with radio collar. This kangaroo was raised by Magrit who allows the juvenile to explore the forest re...

Nick Garbutt / Pack of wolves (Canis lupus). Yellowstone National Park, Wyoming, USA. January.

Laurent Geslin / Young male European lynx (Lynx lynx) running after release in Jura Mountaiins, Geneva canton, Switzerland, May 2013.

Laurent Geslin / Vet and KORA team putting a radio collar on wild European lynx (Lynx lynx) for translocation to Kalkalpen National Park, Austria from Switzerland. May 2011.

Laurent Geslin / Conservationists releasing radio collared wild European lynx (Lynx lynx) from Switzerland into Kalkalpen National Park, Austria, March 2013.

Laurent Geslin / European lynx (Lynx lynx) emerging from crate during translocation from Switerland to Kalkalpen National Park, Austria. May 2011

Hugh Pearson / Leopard (Panthera pardus) resting, Erindi Game Reserve, Namibia.

Neil Aldridge / Portrait of an African wild dog (Lycaon pictus) wearing a radio collar in dense mopane bushveld, Venetia Limpopo Nature Reserve, Limpopo Province, South Africa, February 2010.

Tui De Roy / Haast Tokoeka (Apterix australis) with Phil Tisch and Tansy Bliss, Department of Conservation Kiwi Recovery team affixing radio trnasmitter. Haast Kiwi Sanctuary, Westland, South Island, New Zealand.

Laurent Geslin / Fulani child sitting beside radio and mobile telephone, portrait, North Senegal, West Africa, 2005