Camera trapping

Amur tiger in camera trap

A wildlife camera ‘trap’ is a camera left at a promising location, rigged so any approaching wild animal will automatically trigger the shutter release and take one or more photos or video sequences of itself, without the photographer being present. The first attempts to do this were made as early as 1877.

In the early years camera trapping was rather a specialist and limited activity, mainly because the equipment was bulky and difficult to use, involving bait, weighty cameras and arrays of trip wires. But although the equipment was clumsy, from the outset images obtained this way were especially attractive for the often candid and relaxed behaviour that is captured.

Today camera trapping has been transformed by technology and has become a major tool of the trade for a conservation organisation like ZSL. Miniaturised heat and motion sensors have replaced trip wires and pressure pads. Invisible infra-red flash units provide night time black and white images without the startling effect of conventional flash. Very large numbers of high quality digital images can be stored and modern batteries allow these neat devices to operate unsupervised night and day in remote locations for months at a time. The opportunity learn new things about elusive and shy wild animals, and some of the problems they face, are immense.

How do we use camera traps at ZSL?

A single camera can monitor a key location, such as a nest site or den, providing a history of activities and behaviours of the target species; how much food was brought, when do the animals come and go?. An array of cameras across a forest or mountain can overtime (40 cameras operating for 6 months provide 20 years worth of continuous observation!) provide a uniquely comprehensive description of the larger wildlife using that habitat. Which species are present? When are they active? How frequently do we record them? How many species are present? At what rate do we discover them?

ZSL scientists are using camera trap arrays to study the rare tigers and leopards of the Russian Far East and gain insight into some of the hunting threats affecting them. Profiles of poorly known rare forest faunas along the Kenya coast and the highland rainforests of Guinea have been made and will be compared with results in future repetitions. Camera trap arrays have been used to study the incredibly rare Saharan cheetahs, and dama gazelles, as well as Nubian ibex and small poorly known species such as Blanford’s fox in Arabia.

Other camera related activities include research at the Institute of Zoology to investigate how study of rate of movement can provide estimates of home range and local densities directly for picture sequences. In another configuration cameras set to take daily photos at fixed times are used to study the cycle of greening and drying plants in the Sahara desert and also ebb and flow of nesting in penguin colonies in the Antarctic.