There are several reasons why many of Leuser's animal species have rarely or never been filmed in the wild. The Leuser Ecosystem is a huge area and many animals are nocturnal, scared of people and very rare. Also, the dense tropical vegetation makes it often impossible to see anything beyond a couple of meters and also makes it hard to move around.
To see animals like orangutan, thomas langurs and hornbills is not very difficult; just walk through the forest and you will find them for sure. However, to get a glimpse of Leuser's more elusive animals species such as one of the 8 species of cats, other methods are required.
Video trapcamera's are rapidly becoming very popular. There are several companies that make these devices and they are getting more sophisticated and affordable every year. By using trail camera's, rare animals such as the sumatran rhino on Borneo have only recently been filmed for the first time.
For this project I'm thinking of buying around 10 cams, but I don't know yet which brand or model. There are quite some companies that make these things, but many don't seem to be very reliable. http://www.chasingame.com is a great website to get to know which camera is best.
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