***Updated 15 June***
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Western jackdaw with white feathers Kauw met witte veren 7 April 2023 The Netherlands ©Gert Korthof |
A Western jackdaw ( Coloeus monedula ) with white feathers is rare. It is a mutation in the melanin pigment producing cells in the feathers. For the first time this individual visited our garden and I could make a reasonable good portrait. This individual has been spotted at least the previous year at other locations nearby together with members of his own species. Apparently accepted as a member of the group. It seems to be a healthy and otherwise normal Jackdaw.
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same individual. 7 April 2023. ©Gert Korthof |
Some 5 weeks later, on 15 June, I observed the 'white' jackdaw again on a chimney with a 'normal' partner:
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15 June 2023 ©Gert Korthof |
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15 June 2023 ©Gert Korthof |
Many Jackdaws here use the chimneys as nesting places. So, maybe the 'white'
and the 'normal' Jackdaw are going to produce young Jackdaws... How will
they look like?
= = =
I found many other pictures on the internet. Keep in
mind that rare birds have a higher probability of being published! The more I searched the more I found!
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| By Markus Rantala (Makele-90) - Own work, CC BY-SA 3.0 |
These birds have seemingly random white spots and patches:
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Vroege Vogels:
Kauw in het wit
(2016) |
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Pied Jackdaw
(flickr) |
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Magnificent leucistic jackdaw
(Linda) random white spots and patches |
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| Nice picture by ©Linda |
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Fredrik Grahn To me it looks like a Nordic Jackdaw subspecies (Noordse Kauw) |
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Kauw, afwijkend (waarneming.nl
2006) |
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Darley Dale Wildlife: Partially albino Jackdaw Andy Butler http://darleydalewildlife.blogspot.com |
'Partial albino' is not a correct description. Albinism is the congenital absence of melanin in an animal or plant resulting in white hair, feathers, scales and skin and reddish pink or blue eyes. So, this is a leucistic Jackdaw because it clearly has black pigment.
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source
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White and black Jackdaw together ( BBC ) BBC - Avebury's rare albino faces black future |
Please note that the following bird looks like a leucistic Jackdaw:
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Daurian Jackdaw
(Coloeus dauuricus) (Dmitry Dubikovskiy) |
but do not get confused, the above picture is the Daurian Jackdaw, a
geographic species of the Coloeus genus.
The Hooded Crow (Corvus cornix) is not a leucistic crow but it is the normal color pattern of the species:
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Hooded Crow, Bonte Kraai (
Jeanne Kliemesch
) |
At the Corvid Research blog I found a blogpost about leucism in general with some pictures of leucistic Jackdaws in flight. Corvidae is the family name which includes Eurasian magpie, Common raven, Carrion crow.
Here is a story at the
Garden Wildlife Health website about leucism with pictures.
The
British Trust for Ornithology
writes that leucism is heritable, but I think this is not always the case.
When the mutation happens after fertilization, thus during
development of the embryo, it is a somatic mutation, and does not occur in
the germline. So, is not heritable.
Finally, a video with a very rare and amazing White Blackbird:
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Leucistic Blackbird
video (A Shot Of Wildlife) |
Last but not least: an extreme form of Jackdaw leucism:
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Jackdaw extreme leucism! (
flickr
) |
Automatic species identification software:
The most amazing fact: the rare white blackbird is recognized by
ObsIdentify-NIA
as a Blackbird with 97%! How on earth is he doing that?
Interestingly, all the other leucistic Jackdaws are identified by
ObsIdentify-NIA with 99%-100% certainty as a Western Jackdaw except the
picture by Fredrik Grahn which is identified as a
Nordic Jackdaw
(Noordse Kauw) with 100% certainty. The Noridc Jackdaw is considered a subspecies:
Western Jackdaw ssp monedula. The software is able to identify the Jackdaw despite the white
feathers: how does he do it? [ 6 May ]
Further Reading
- Leucism & albinism at the British Trust for Ornithology website explains that leucism is heritable. Leucism is different from Albinism.
- Leucistic plumage as a result of progressive greying in a cryptic nocturnal bird, Nature, 01 March 2022. This is a scientific study of leucism in a nightjar species (Caprimulgus ruficollis) during a 4 year period. The authors discuss several hypotheses about leucism. [ added: 9 May 2023 ]
- Why Is That Bird Part White? Leucism! BirdNote, 2018. with a gallery of different species with leucism. [ added: 9 May 2023 ]
- Mandarijneend met witte vrouw (blog) Mandarin Duck (Aix galericulata) with white female. 18 May 2020. [ added: 19 May 2023 ]
