Melopsittacus undulatus
budgerigar

Melopsittacus undulatus, commonly known as the budgerigar, is naturally distributed through Australia except for coastal areas in the far east and the far south-west. This species has also been introduced to many areas around the world including S. Africa, Japan, U.S., Puerto Rico, Switzerland, and New Zealand, however, they have only successfully been established in southwest Florida (Juniper, 1998).

Budgerigars occupy a range of semi-arid and sub-humid habitats mainly in the interior of Australia. However, they sometimes can be found in dry grasslands of the southeast. Although mainly restricted to the interior of the continent, there are occasional coastal interruptions in the northeast and in the central south. They seasonally migrate to the north during the winter in order to have a continuing food source (Juniper, 1998).

Budgerigars are small, streamlined parrots that average 18-20 cm in length. They are unlikely to be mistaken for any other parrot because of their small size, pointed wings and tails, and distinct plumage patterns (Juniper, 1998). Most wild budgerigars have a yellow forehead (juveniles have a barred forehead), a yellow and black striped head with purple and black markings on the cheeks, a pointed bill whose tip of the upper mandible extends over the lower mandible, and a yellow throat. Their lesser and median wing coverts are centered black and outlined in yellow. Both their greater coverts and flight feathers are centered black and outlined with green and yellow, but their flight feathers also have a central yellow bar. Their uppertail coverts are bright green and extend to a blue-green tail. Caged species differ greatly in their plumage color and patterns (Phillips, 2000).

There is slight sexual dimorphism. In breeding females, the cere (the skin at the base of the bill, covering the nostrils) is light brown or beige. Otherwise the cere is blue. (Forshaw 1977)

Budgerigars aggregate into large flocks and are strongly social. Their grouping allows for greater success in feeding and also helps in protection from predators. There does not seem to be any hierarchy in groups based upon the relatively few battles among individuals, but females are generally more aggressive than males.

Their activity, like most birds, begins just before sunrise with preening, singing, and movement within trees. After sunrise, the birds fly to the foraging area and feed throughout the day. They do not forage during midday or in extremely hot weather, instead they take shelter under shade and remain motionless. At the end of the day, they congregate by calling loudly and flying at high speeds around the trees. They then return to their roosting site just after sunset and remain at rest until the next morning (Kavanau, 1987).

Budgerigars are highly successful exploiters of food and water resources whenever available (Kavanau, 1987). They are ground-feeders and thus prefer to take the seeds of grasses and crop plants, particularly spinifex and tall tussock grasses. They first dehull the seed and then swallow it whole or broken. These seeds are extremely energy rich and are equivalent to the caloric content of animal tissue. Therefore, no alternate food source is necessary. Budgerigars are very scheduled in their drinking habits and drink about 5.5% of their body weight daily (Kavanau, 1987). To satisfy this demand, they often locate themselves near water holes. (Kavanau, 1987)

Their ability to consume a large number of seeds when in groups concerns farmers.

Budgerigars are the most widely known pet bird in the world (Phillips, 2000). Their population of about 5,000,000 worldwide has allowed scientists ample opportunity to study them. In fact, more is known of their biology than of any other parrot.

None known.

Budgerigars are the only bird known to use their feet for scratching the sides of the crissum (undertail coverts). According to Kavanau, Budgerigars exist in more color varieties than most other species of bird or animal (Kavanau, 1987). The scattered colors of their plumage are accentuated in ultra-violet light, especially the sides of their cheeks, which may play a part in sexual dimorphism. Check out http://www.budgies.org/info/breeding/hatching.html for an amazing video of Budgerigars hatching.