Camera trap

A camera trap is a remotely activated camera that is equipped with a motion sensor or an infrared sensor, or uses a light beam as a trigger. Camera trapping is a method for capturing wild animals on film when researchers are not present, and has been used in ecological research for decades. In addition to applications in hunting and wildlife viewing, research applications include studies of nest ecology, detection of rare species, estimation of population size and species richness, as well as research on habitat use and occupation of human-built structures.

Camera traps, also known as trail cameras, are used to capture images of wildlife with as little human interference as possible. Since the introduction of commercial infrared-triggered cameras in the early 1990s their use has increased. With advancements in the quality of camera equipment this method of field observation has become more popular among researchers. Hunting has played an important role in development of camera traps, since hunters like to use them to scout for game. These hunters have opened a commercial market for the devices which have led to many improvements over time.

The great advantage of camera traps is that they can record very accurate data without the photographed animal. These data are superior to human observations, because they can be reviewed by other researchers. They minimally disturb wildlife and can replace the use of more invasive survey and monitoring techniques such as live trap and release. They operate continually and silently, provide proof of species presence in an area, can reveal what prints and scats belong to which species, provide evidence for management and policy decisions, and are a cost effective monitoring tool. Infrared flash cameras have low disturbance and visibility. Besides olfactory and acoustic cues, camera flash may scare animals so that they avoid or destroy camera traps. The major alternative light source is infrared, which is usually not detectable by mammals or birds.

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Wikipedia