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Effective monitoring of endangered species is key to their survival.  Studying the movement, range and habits of wild animals is essential in order to ensure their habitat remains free from poachers and development. Traditional methods of monitoring wild animals, especially large ones, include radio-tagging. To do this, individual animals must at first be captured or sedated so that collars or tags can be fitted.
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One organisation that adopted this technique was WildTrack. In the late 1990s, the team was using radio-collars to monitor black rhino in Namibia. However, the team soon realised that the chemicals used to immobilize the rhino in order to fit the collars had a negative impact on female fertility. Not only that but a large proportion of the radio-collars failed within the first 6 months and had to be replaced. Moreover, as animals grew, the collars would tighten, irritating or even hurting the animal. The method was not only expensive, but it was also counterproductive, as it altered the rhino’s behaviour, thus invalidating the data collected.
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 At the same time, the team was worked alongside local trackers. Animal tracking is one of the oldest human skills, and these experts had years of experience in identifying individual animals by their footprints. They could effectively create a true picture of individual rhinos’ activities without the use of any invasive techniques. Consequently, the team were interested to know whether the trackers’ knowledge could be successfully translated into an effective, computerised technique for monitoring animal movement. 
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Within each species, each individual has its own unique foot characteristics, in the same way that humans have fingerprints. Thus, if an animal is sighted and identified just once, and the characteristics of its footprints properly photographed and measured, its footprint can be recognised whenever it is sighted again. If done repeatedly, conservationists can draw up a database of all, or at least a significant proportion of the individuals within the population. After that conservationists can use it to identify an animal and its movements by its print. The data gathered can be used for a range of purposes, for example to monitor biodiversity. WildTrack is currently using footprint identification technology in Greece to study the potential effect of a large highway construction through brown bear habitat.
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Identifying an animal from its footprint is not without its challenges, however, as each time the individual places its foot on the ground, it leaves a slightly different track, according to the type of ground it is walking on, moisture levels and the way it is moving. In order to account for these variations, it is necessary to collect several tracks from each individual, including impressions from all four feet, on a range of surfaces.