Feather duster budgerigars (''
Melopsittacus undulatus
The budgerigar ( ; ''Melopsittacus undulatus''), also known as the common parakeet or shell parakeet, is a small, long-tailed, seed-eating parrot usually nicknamed the budgie ( ), or in American English, the parakeet. Budgies are the only spe ...
''), sometimes called budgerigar mops, are
budgerigars
The budgerigar ( ; ''Melopsittacus undulatus''), also known as the common parakeet or shell parakeet, is a small, long-tailed, seed-eating parrot usually nicknamed the budgie ( ), or in American English, the parakeet. Budgies are the only spe ...
that have a condition characterised by overly long
feathers
Feathers are epidermal growths that form a distinctive outer covering, or plumage, on both avian (bird) and some non-avian dinosaurs and other archosaurs. They are the most complex integumentary structures found in vertebrates and a premier e ...
that do not stop growing at usual periods, giving the bird the appearance of a feather duster. This condition is sometimes known as chrysanthemum feathering. The contour, tail and flight feathers do not stop growing, and they do not have the necessary
barbs and
barbule
Feathers are epidermal growths that form a distinctive outer covering, or plumage, on both avian (bird) and some non-avian dinosaurs and other archosaurs. They are the most complex integumentary structures found in vertebrates and a premier ...
s for the feather's structure to interlock. The shaft (calamus) is also curved, and so the feathers appear deformed and fluffed out. Individuals with this condition often appear less alert than nest mates. In addition, they are small and some have other defects such as
microphthalmia
Microphthalmia (Greek: grc, μικρός, mikros, small, label=none, grc, ὀφθαλμός, ophthalmos, eye, label=none, also referred as microphthalmos, is a developmental disorder of the eye in which one (unilateral microphthalmia) or both ( ...
. They lack vigour, often cannot fly and die within a year of hatching. There is no treatment for the condition; birds are often euthanized in the nest.
The condition may be a genetic disorder,
caused by a
herpesvirus
''Herpesviridae'' is a large family of DNA viruses that cause infections and certain diseases in animals, including humans. The members of this family are also known as herpesviruses. The family name is derived from the Greek word ''ἕρπειν ...
,
or perhaps caused by both.
See also
*
Whipper (budgerigar)
Whipper is a budgerigar from Winton, Southland District, New Zealand. His unusual appearance, long curly plumage, and vocalisations, which were caused by a genetic mutation called "feather duster" a very rare mutation, made him famous in his home ...
References
{{Budgerigar mutations
Broad-tailed parrots