Zoo Volunteer: New arrivals: The Gouldian Finch

Friday, 5 June 2015

New arrivals: The Gouldian Finch

Gouldian finches, normal and white-breasted forms

Now on view in the small aviary behind the wallaby walk though is a small flock of one of the most colorful small birds in the world, the Gouldian Finch. This is one of the most distinctive of the Estrildid finches, a group commonly referred to as waxbills, which also include such familiar cage birds as the Zebra finch and Java Sparrow, although they are most closely related to the equally colorful parrot finches which are mostly found in more humid environments in southeast Asia and New Guinea.Originating from northern Australia, they are now classed as Near Threatened by the IUCN, and have a population in their restricted range of probably only a few thousand individuals, split into several much smaller sub populations

Zebra Finch

Estrildid finches are mostly ground feeding birds, specializing on small seeds of grasses and low growing plants. Many species also feed heavily on insects, especially when raising their young, although Gouldian finches not seem to feed on any insects at all, even when breeding, but raise their young on unripe grass seeds.

They have experienced a drastic reduction in population in the last 50 years. Originally this was thought to be due to competition with invasive birds such as house sparrows, but more recent research has shown that a major threat is a combination of overgrazing and changes in fire management. This has reduced the availability of native grass seeds, and has also reduced the availability of suitable holes in the old eucalyptus trees where they make their nests. In addition, they face competition for the remaining nest sites with Long-Tailed Finches, which are more aggressive and out compete them.

Long-Tailed Finch

Conservation measures currently in place include protection of the wild populations and a nest box scheme, which has proved quite successful in boosting nest productivity. There is also a large captive population in Australia, which might be used for release programs if necessary, although there are no plans for this at present.

Outside Australia, the Gouldian Finch is a popular cage bird. The chief issue with their care is that they are somewhat sensitive to cold and wet, and require dry, preferably heated, quarters in the winter months. They breed readily in cages, and many are bred by private owners in Bristol alone each year. These domesticated birds however have often been selected for color mutations from the original wild type bird, and some of the birds on show are of one of these, the “White Breasted” mutation.

Red and Yellow-Head morphs

One feature however of these birds is that even in the wild they come in three head patters, red, black, and yellow. These color patterns are under genetic control, with red dominant to the others and yellow recessive. In the wild, most birds are black headed, with a few red headed and even fewer yellow headed. Both males and females can be of any head color, but the females have less intense colors. Interestingly, the colors seem to vary in their behaviour – red heads are dominant to the other colors in the flock, whereas yellows are subordinate to the others but are quickest to locate new food sources.