Vasa parrot

The name Vasa Parrot is also used for the Greater Vasa Parrot.
Vasa Parrot
Lesser Vasa Parrot
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Psittaciformes
Family: Psittacidae
Subfamily: Psittacinae
Tribe: Psittacini
Genus: Coracopsis
Wagler, 1832
Species

The vasa parrots (Coracopsis) are two species of parrot which are endemic to Madagascar and other islands in the western Indian Ocean.

Contents

Taxonomy

There are two species and several subspecies:[1]

Coracopsis, Wagler 1832

Additionally, a recent study using ancient DNA shows that the Mascarene Parrot is positioned in between the various subspecies of the Lesser Vasa Parrot;[2] however, the binomial name of the Mascarene Parrot has not been officially updated.

Description

They are notable in the parrot world for their peculiar appearance, which includes extremely truncated bodies with long necks, black to grey feathers and a pink beak.

The skin of both female and male vasas turns yellow during the breeding season, and there is often feather loss. However in females the feather loss can result in complete baldness. Another interesting feature of the females breeding physiology is when her feathers, which are usually black to grey, turn brown without a moult. This is caused by the redistribution of melanin, which is the pigment that makes the vasas' feathers black.

Unusual characteristics

In addition to their appearance they possess aspects of their physiology that make them completely unique amongst parrots. Vasa chicks are known to hatch after only 18–20 days of incubation, which is highly irregular as parrots of the vasa size range tend to take up to 30 days to hatch.

The male vasas' cloaca is able to invert into a hemipenis, which becomes erect during mating - a feature unique to the genus. This phallus is associated with prolonged matings enforced by a copulatory tie.[3] Baby vasas possess pads on their beaks which when stimulated prompt a strong feeding response. These pads disappear after only a few weeks, however the feeding or 'weaning' reflex remains unusually strong well into adulthood. Often aviculturalists have to use a syringe to force food into the crops of young vasas as the intensity of the weaning reflex prevents them from being spoon fed.

Vasa parrots infected with the debilitating psittacine beak and feather disease are known to turn white, which, during the 1970s when the first wave of birds were exported into Europe and America, resulted in them being mistakenly advertised by importers as albinos.

References

  1. ^ "Zoological Nomenclature Resource: Psittaciformes (Version 9.020)". www.zoonomen.net. 2009-03-01. http://www.zoonomen.net/avtax/psit.html. 
  2. ^ S. Kundu, C.G. Jones, R.P. Prys-Jones & J.J. Groombridge (In Press). The evolution of the Indian Ocean parrots (Psittaciformes): Extinction, adaptive radiation and eustacy. Molecular Phylogenetics and Evolution.
  3. ^ Ekstrom, J. M. M.; Burke, T.; Randrianaina, L.; Birkhead, T. R. (2007-01-22). "Unusual sex roles in a highly promiscuous parrot: the Greater Vasa Parrot Caracopsis vasa". Ibis (Wiley) 149 (2): 313–320. doi:10.1111/j.1474-919X.2006.00632.x. 

External links