The way to collect data depends on the subject of each project, although behavioural data are always collected using ethograms. Between most orangutan field sites the ethogram is standardized to optimize the comparisons of orangutan behaviour between different regions. An ethogram is a table to fill in behaviours the orangutan (focal) is doing, such as resting, eating (what, how high etc.), moving, association with other orangutan(s) (having a ‘party’), copulating and so on, during following. Other common ways to gather behavioural data are to make film and/or audio recordings. This is often an addition to the ethogram.
To start collecting data one first must find an orangutan.
A searching day starts usually at 6 o’clock in the morning after dawn. By walking
slowly and by listening, an orangutan can be found in the forest, although
this is very difficult. Sometimes an orangutan is found within one hour;
sometimes it can take several days or weeks. Orangutans can be found
by movements, feeding smacks or even smell. After finding, following
hours start and prolong until the orangutan makes a night nest which
is highly variable in time per orangutan per day (ranging from 2.30 p.m.
until 8 p.m.). After making this nest and the researcher is sure the
orangutan will stay there for the night, the place is marked. This is
to make sure that the next morning the nest can be found again. An orangutan
usually wakes up early (around 5 a.m. on Borneo and 6 a.m. in Sumatra).
Before this happens one must be at the nest, this means that on following
days the time to wake up is around three o’clock at night (which
also depends on the distance the nest is from camp). An orangutan can
be followed for a maximum continuous period of 10 days. After that, it
is time to give the orangutan some rest for at least a month. This maximum
period is set mainly to avoid extreme habituation to human presence.