Leaving her London desk behind, ZSL's Sam Roberts grabbed her binoculars and headed to Kenya to join the team of rhino trackers in Tsavo, Kenya. ZSL has worked closely with Kenya Wildlife Service to conserve black rhinos since 1993.
Tsavo National Park, which comprises Tsavo East and Tsavo West, is a whopping 21,812km2 of wilderness, making it Africa's largest wildlife protected area.
Sam got to see first hand the many methods that Tsavo's rangers use to track these magnificent animals.
Tsavo's vast size is a blessing for conservation and wildlife, but it takes a massive amount of resources - vehicles, aircraft, fuel and hundreds of rangers - to protect and manage a conservation area this vast.
After three bad rainy seasons with very little rain, water and vegetation are extremely scarse in this area. These hippos are crammed into a tiny pool.
Rangers use a variety of methods to track down rhino. Vehicles like this allow the rangers to get close enough to identify and monitor the condition of the rhinos using binoculars.
One of the best methods of spotting rhino has to be by plane, allowing the team to cover the park's vast wilderness much better than by off-road vehicle.
The photo gives you a small indication of the vast area the rangers have to cover - a very hard task indeed!
Rangers on the ground can pick up signals from rhinos that have been fitted with special radio transmitters.
Every rhino that has a transmitter has it’s own frequency, which can be tracked using directional antennae. The rangers follow the signal on foot carefully and quietly making sure they stay down wind, so the rhino doesn’t smell them.
The waterholes in Ngulia rhino sanctuary, which is located inside Tsavo West National Park, are pumped with water.
To the right of this waterhole is a hide where the rangers can monitor the rhino safely, and in close proximity, whilst they come to drink.
The black rhino are solitary creatures which are difficult to see, unlike elephants we can be seen close to the road.