EEP Crowned pigeon number 4

EEP STUDBOOK CROWNED PIGEONS
6.4 Comparison in time-budgets between crowned pigeons
kept under different housing conditions
Introduction
Because of the fast growth of the human population, the increase of tourism and the rapid
growth of the number of industries, the undisturbed part of the island of New Guinea is
declining quickly. Because crowned pigeons are an easy prey to hunters, they disappear
everywhere where humans occur. Because remote areas are disappearing very rapidly the
number of crowned pigeons in the wild is declining just as fast. Now the numbers are
declining very quickly, conservation institutions feel the urge to establish a sustainable
population in captivity. Because of the negative natural growth of the population, research is
continuously carried out into different aspects of the ex situ husbandry.
The most important problem is the low birth rate in captivity. Data from zoological
collections show that crowned pigeons must be able to produce and raise three clutches a year
in captivity and that they are able to produce fertile eggs for over twenty years. At first sight it
should be easy to maintain a stable population in captivity (Nijboer and King, 1996).
Unfortunately, the current situation is not prosperous and for that reason the EEP Speciescommittee
proposed an ex situ research project into the wellbeing and reproduction of
crowned pigeons in captivity.
The main problem is the big loss of eggs and squabs, as a result of a lot of infertilized eggs.
Furthermore a lot of embryos are dying during incubation. Also a lot of eggs are demolished
or thrown out of the nest. Only one out of six eggs will finally deliver a new mature crowned
pigeon (Nijboer and King, 1996). Many scientists advice to conduct research into the
accessibility of the nest and the care of the parents for the squab (King, Nijboer and Wiersma,
1996; King and Nijboer, 1996). Some of them also state it is important to conduct research
into the fact that only a low number of crowned pigeons are producing eggs (King and
Nijboer, 1996). Apart from this the condition of the toes of most crowned pigeons seems not
to be very well. In most cases the nails are too long or the birds are not able to bow their toes
(King, pers. comm.). As a consequence, it is likely that the males have problems to copulate,
because they are not able to hold the hen. This should reduce the chance of a successful
mating. It might be possible to improve the condition of the feet by changing the thickness of
the perches and by using a different kind of substrate.
The target of the research project in zoos was to improve the wellbeing of crowned pigeons in
captivity by improving the reproduction of crowned pigeons ex situ. To reach that goal the
following research questions were formulated:
� What is the time budget of crowned pigeons under different circumstances/housing
Guinea conditions?
� Do the perches influence the well being of them and, as a consequence of that, the
reproduction of crowned pigeons?
� Does the substrate have any influence on the time budget of crowned pigeons?
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