The opposite occurs with the presence of high levels of stress. Under optimal conditions a 2-month old chick would finish molting and start nesting. In the wild it was sometimes possible to see a very early adolescence of young chicks. In the areas where the wild population lives, the night temperatures during nesting season average at 19☌ and day temperatures average at 33☌. During a good year with a lot of rainfall, and a lot of food as well, nesting season may grow longer, which means up to three lays during nesting season. During a dry year, the length of nesting season is shorter and it consists of one, at most two nestings. The amount of rainfall and the length of wet season are different every year, so in Gouldian Finches we may also observe seasonal, so called opportunistic (adapted to certain conditions), nesting. The following wet season, which brings plentiful harvest of seeds of the local kinds of grass, provides the independent offspring a reliable source of nourishment, for the time remaining until molting season. The beginning and the duration of their sexual activity overlaps with the period of high quality food source availability in their natural habitats. At this time, the production of sex hormones increases, which encourages mating and the birds start to seek nesting cavities. For the population of Gouldian Finches in the wild the nesting season starts in the late wet season (March and April) the first raindrops stimulate the growth of seeds (Sorghum spp.), which are a highly nutritious food source. Sometimes, nests built in tall grass or low thickets may be seen.ĭue to developed social instincts and considering the deficiency of appropriate nests, it is possible to see more than one pair living in a single nest cavity and successfully raising their offspring there. These birds build their nests especially in cavities abandoned by parrots, mainly budgerigars or other cavity-nesting birds. The presence of a large quantity of Eucalyptus – gum trees in these areas, such as the favored salmon gum or white gums growing further north, is a very important prerequisite for the availability of nesting cavities. Sorghum, Vacoparis spp., bluestems - Schizachyrium spp.) which are available mainly during molting season and are a better source of nutrients than perennial grasses, such as Spinifex and grasses of the Kakadu region at the beginning of wet season. Gouldian Finches have a more exclusive diet compared to other seed-feeding birds. These birds avoid human housing however they are quite social and form colonies. Shallow waterholes protected from predators are convenient. They need to drink every day, so viable water sources are a necessity.
These birds drink by drawing water and drink a lot considering their weight. High temperatures are the reason, why these birds look for habitats with water sources. In southern parts of their habitat, where the temperature is lower than in the north, it is 22☌ on average. Night temperatures vary, but rarely go under 20☌. In the area populated by Gouldian Finches the maximum temperature goes over 40☌ and even during wet season it stays as high as 30☌.
Gouldian Finches avoid dense woods and they also do not live in the tropical forests of Cape York Peninsula. Usually, it is a bright eucalypt savanna. The land, where these birds live is scarcely populated. The grassy undergrowth of the woodlands in the area of Gouldian Finch habitats provides a food source in times when seeds are scarce and throughout the wet season. The lay of the land, not to mention natural barriers, such as rivers and streams, stop the spreading of wildfires and thus reduce their impact on the availability of food – grass seeds. For the survival of the population the number of landscape elements is very important, for example large areas of craggy hills with dense vegetation, including endemic grass undergrowth, characteristic for the natural nesting season biotopes of these birds. In the wild, these birds populate the northern part of the Australian continent they live as far south as 19° southern latitude.
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