EEP Crowned pigeon number 4

EEP STUDBOOK CROWNED PIGEONS
Comparison with “natural” situation
Burgers’ Bush gives the crowned pigeons the most possibilities to conduct the behaviour they
want. This enclosure has all elements of the other enclosures, and more. The time spent on
conducting behaviour in time, “care”-behaviour and metabolic behaviour decreases if the
enclosure is larger and more varied. In the more natural environment of Burgers’ Bush, the
crowned pigeons spent more time conducting social behaviour. But this also can be explained
by the fact that these birds were incubating an egg.
Correlation between male and female
The behaviour of the male and the female are correlated in many types of behaviour. Only if
the birds were incubating an egg, there was no correlation, which can be explained by the fact
that incubating is a solitary activity.
The metabolic behaviour was highly correlated; after feeding time, both birds started to eat. In
Burgers’ Bush this correlation was less, because food was available all day.
In some enclosures the behaviour was also correlated, probably because the birds would like
to build a nest and they were looking together for nesting material.
In Rotterdam Zoo the behaviour of the male and the female were also highly correlated, but
this can be explained by the small enclosure-size.
Use of the substrate
With use of a Fishers Exact Test it became clear that crowned pigeons have a preference for
foraging on the mould and preening on the sand. In most enclosures the mould was planted
and regularly leaves felled down, which were studied well by the birds. Furthermore the
texture of the mould is different and the birds had to go with their bill into the mould to find
out if there was something to eat. In sand this is not necessary. Also the mould can be
considered as a place where food can be found, while the sand might be an open spot in the
forest, where the crowned pigeon has a lot of space to preen. Both foraging and preening are
important to the birds. If foraging is replaced by preening, they are preening too much which
causes damages onto their feathers. The birds in Rotterdam Zoo looked worse than their
congeners who had also mould available.
Discussion about the results
Experimental research project
In the experiment with perches, where at random a thick and a thin perch was placed, four out
of six crowned pigeon showed no preference for one of the types of perches, while the other
two crowned pigeons preferred the thick one. The hypothesis, formulated after research
carried out in Burgers’ Bush (where the birds can choose between thousands of perches), was
that crowned pigeons should prefer thin branches, where they are better capable to bow their
toes for a better grip. The strange results (in comparison with the hypothesis) can be explained
by the fact that crowned pigeons are very susceptible to changes in their environment. It
always lasted several days for them to get used to something new, and in Birdpark Avifauna it
even lasted seven weeks!
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