EEP Crowned pigeon number 4

EEP STUDBOOK CROWNED PIGEONS
The egg produced by scheepmakers crowned pigeon is about 52.0 x 37.5 mm (Coates, 1985).
Both birds incubate the egg and they relieve each other at about 24 hours. The male takes a
full share of parental duties. Both sexes incubate and brood for about the same number of
daylight hours, both produce crop milk and feed the young (Goodwin, 1983). Crop milk is a
white, slimy caseous material formed by the desquamation of epithelian cells in the crop
(Davis, 1939, in Clawitter, 1990). Incubation time in all three species is about 28 (Fleay,
1961) till 30 days (Klös, 1966; Assink, 1988). Assink studied the incubation time in captivity
by sending questionnaires to zoos. He found a range of 22 - 39 days in victoria crowned
pigeons and 26 - 32 days in scheepmakers crowned pigeons. This can be explained by the fact
that the bird keepers do not check the nests of eggs and hatchings every day, to not disturb the
birds.
Crowned pigeons are a very hygienic species. Just like other ground-pigeons, which do not
nest on the ground, they always keep their nest clean. Their nest sanitation might serve to
make the nest and young less conspicuous or odiferous to potential predators and / or to keep
the nest in a condition where it will quickly dry out after rain.
The parents seldom leave their eggs, chick alone unless the incubating parent is forced to flee
from the nest (Goodwin, 1983). In Burgers' Zoo the crowned pigeons were housed with
hundreds of other animals in a huge eco-display (90 x 130 m). A pair of blue-throated pipingguanas
(Pipile cumanensis) lied in wait for the egg and because of this threat the crowned
pigeons procrastinated the relief. They relieved each other very careful and sometimes the
crowned pigeons were even sitting together on the nest to protect the egg against the guans.
Thanks to the very careful and active parent, who will both feed the chick (the first days with
their crop-milk, later with other food), the chick will gain weight very fast, although
according to other sources the development of the chick is very slowly in comparison to other
Columbiformes (King and Nijboer, 1994). Two weeks after birth, the chick is already
completely feathered. It fledges after about 28 to 30 days (AZA, 1996). Assink found in the
responses to his questionnaire also a lot of variation: common crowned pigeons 28 - 40 days,
victoria crowned pigeons 20 - 31 days and scheepmakers crowned pigeons 27 - 30 days
(Assink, 1988). Apart from false records because of not exact and very few data, it is expected
that there is more variation in fledging time, because of more external influences, like food
composition, temperature, threats and of course both parents.
Pigeons learn to recognize their young as individuals about fledging time. Therefore, a young
crowned pigeon taken from the nest by human beings, will preen on men in stead of on other
crowned pigeons and it will never produce a chick of its own (Goodwin, 1983).
In comparison to fruit pigeons (who fledge after 12 days), this is extremely late (Goodwin,
1983) As the young crowned pigeon fledges, it is about one third of his parents size. Firstly it
is completely fed by his parents, but after a few days on the ground, it starts looking for its
own food little by little. Two or three months after fledging, depending on the behaviour and
care for the young, the parents pay less attention towards the young bird (King and Nijboer,
1994). Fleay reported that a victoria crowned pigeon fledged at four weeks old when it could
fly very well although only about a quarter the bulk of the adult. It was fed by the parents
until 13 weeks old. Sometimes the crowned pigeons start breeding again in captivity and in
this way a pair of crowned pigeons can raise up to three chicks per annum. Adult birds are
capable of recycling within 14 to 30 days after losing an egg (AZA, 1996), when the egg is
infertile, the hatching dies of fledges (Assink, 1988).
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