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Gouldian Health Book
By Dr Rob Marshall

Part 1
The Gouldian in Nature

• Introduction
• Gouldians in Nature
• Breeding In Nature
• Moult in Nature

Introduction
The glorious colour of the Gouldian's plumage is equally matched by its appealing nature. Shy in nature but gregarious in an aviary with its own kind it had a reputation of being one of the more difficult finches to breed.

Nowadays, with increasing knowledge it has become a much easier finch to breed. The Gouldian Finch can be a prolific breeder and a joy to keep when its behaviour in the wild and idiosyncrasies in the aviary are understood. This knowledge allows for its special needs to be met.

The breeding of "coloured" mutations presents a completely new challenge for Gouldian breeders. The problems of "Normal" Gouldians are magnified in these far more sensitive and fragile coloured birds. Rarely are the coloured mutations in parrots and finches as beautiful as the colours in Nature, and the normal coloured Gouldian is a jewel in the crown of the bird kingdom. The colour combinations of mutation Gouldians can also be as stunning as the audacious hues of nature's Gouldian.

In this book normal coloured Gouldians are referred to as "Normals" and colour mutations as "Mutations".

Gouldians in Nature
Gouldians are classified as tropical finches. They breed within Savannah Woodlands and Scrublands of tropical Northern Australia, extending from Derby (West Australian coast) in the west to Burketown (north-west Queensland) in the east and about 180 latitude level with Halls Creek to the south. Breeding follows tropical summer rainfall patterns and may extend into winter after good summer and autumn falls. Temperatures across the range are high in summer but evaporation of water is far less than for the arid zones. Grasslands are suited to this environment and occupy much of the ground cover. These sheltered woodlands provide Gouldians with their daily requirement of grass seeds. In Nature Gouldians flock together and are more easily observed at water holes during the breeding season or when low rainfall and drought forces them to gather near scarce water soaks or holes.

Flocks of between thirty and one hundred birds may congregate at such water points in hot months and leave in small flocks of no more than thirty birds. In the wild, males outnumber females in a ratio of two to one (Pers. communication: Ray Ackroyd). During the wet season when water is plentiful they disperse making it almost impossible to follow their activities (Pers. communication: Ray Ackroyd). From one year to the next the climatic and seasonal conditions do vary considerably and Gouldian behaviour may vary accordingly. This fact explains the sometimes-conflicting opinions and observations of naturalists and researchers.

The Gouldian Finch is said to be a dietary specialist with seeds of annual grasses being important during the dry season and seeds of perennial grasses being important during the wet season (Dostine: Wildlife Research 28(4).2001). The dry season extends from April to November and the wet season from December to March. The start of the seasons may vary slightly from one year to the next depending upon prevailing climatic conditions.

After rain, the natural habitat of Gouldians provides an abundant supply of seeding grasses and long lasting water supplies. In Northern Australia most rain falls between December and March. During this time - the so-called wet season - Gouldian finches feed on seeds of perennial grass species including Themeda triandra, Alloteropsis semialata, Chrysopogon fallax and Heteropogon triticeus (Dostine: Wildlife Research 28(4).2001). It is the nutritional diversity and richness from these plants that prepares the Gouldian to breed. After a good wet season these perennial summer grasses may continue to seed for some time and together with annual grasses (e.g Spear grass -Sorghum spp.) create a breeding season that may span from January to June. Spear-grass is an especially prominent part of the Gouldians diet during the dry season (Dostine; Emu.102(2).2002).

By June breeding has finished (Ray Ackroyd 2003) although Tidemann (Emu.99(3).1999) noted egg laying to occur from January to August.

Juveniles remain "green" until August after which time they start to moult. The speed of the moult varies according to the availability of food. Wild Gouldians trapped in August and then provided with a continual supply of seed have completely coloured up by the end of September (Personal communication Ray Ackroyd 2003).

Spring is the natural time of the moult for Gouldians. In Nature the supply of food in spring is often limited after drought and the primary moult of juveniles will be more protracted. Moult at this time becomes a stressful event for Gouldians of all ages but especially for juveniles. After good summer rains a spring flush of seeding summer grasses is probable and may provide the improved level of nutrition required for a rapid growth of new feathers.

Drought conditions may have prevailed when Dostine and Tiddeman (Corella 22(3)1998) noted that "juvenile Gouldian Finches moult at a time of year when food availability is low. Juvenile Gouldian Finches tend to moult at the same time of the year as each other regardless of age. Post juvenile primary moult was much slower than that of the adults."

After drought, post-moult plumage colour of Gouldians in Nature may be more subdued and carry less sheen than healthy captive birds . Vivid "blood" fusion lines up to 1.5mm (1/16") wide and glossy feathers may however be seen during good seasons (Personal communication Ray Ackroyd 2003).

Wild Gouldians have the capacity to produce high numbers of offspring within a short space of time, producing between five and eight eggs per clutch and an egg-laying interval of 8 weeks, but this is an uncommon occurrence in Nature.

Tidemann (Emu.99(3).1999) recorded an average clutch size of 5 eggs and up to three clutches after a good season. Gouldians have adapted, however, to take advantage of breeding opportunities in their natural environment because drought is a recurrent threat in this part of Australia. In poor seasons these "breeder friendly" habitats become harsh and inhospitable for survival, let alone breeding. In order to survive drought conditions, Gouldians, like Budgerigars become nomads. Mike Fidler states: "It (Gouldian Finch) does not breed in the northerly part of its range, migrating southward before breeding (in the wet season) and migrating northward in the dry season following the breeding season".

Gouldian finches undertake regular seasonal shifts in habitat, from breeding areas in hill woodland in the dry season (breeding) to adjacent lowlands throughout much of the wet season, in response to seasonal changes in food availability. There is an annual pulse in abundance of fallen seed in the early dry season (the height of the Gouldian finch breeding season) that is depleted to near zero levels by the end of the dry season. From this time Gouldians depend upon seed from other sources principally ripe and ripening seed or perennial grasses (Dostine: Wildlife Research 28(4).2001).

In the wild, the breeding behaviour of Gouldian Finches follows a similar pattern to that of the Australian Budgerigar. Both respond sexually to the coming of seasonal rains that represent the imminent full growing time of plants and grasses. Gouldians, however, are not opportunistic breeders and have a well-defined breeding season. They must eat every day in order to survive and when food supplies run low they become nomadic.

Gouldians may be identified by their distinctive flight pattern from a distance (Pers. Communication Ray Ackroyd 2003). They do not fly with the typical undulating pattern of other grass finches. They ascend to great height and use prevailing winds to carry them across their tropical range in search of new seeding grasses and nearby water.

Gouldians start to breed in summer, and in the wild this breeding pattern is closely aligned to the summer rainfall of Northern Australia. In the tropical regions of Northern Australia, summer rainfall patterns prevail with worthwhile falls most likely to occur during the second half of the wet season between December and March. The breeding season commences in summer (between December and March) and, depending upon seasonal rains, ends by the beginning of winter in June (Pers. Communication Ray Ackroyd 2003). The wet season determines the start and extent of the Gouldian’s breeding cycle. The start of the wet season may vary from year to year and is dependent upon monsoonal activity further north and west of Australia.

Black head Gouldians are the dominant colour in Nature and Yellow head Gouldians are rare (1 per 2000 birds). Ray Ackroyd has never seen a mutation Gouldian in the wild.

El Nino events, which occur every 4-7 years, also have a major effect on the start of the wet season. The consequence of El Nino events varies according to their intensity. An intense El Nino results in drought and often a failure of Gouldians to breed. "Normal" years result in monsoonal activity starting in November and extending through until April. Breeding success and therefore Gouldian numbers in Nature may wax and wane according to the intensity of the El Nino and La Nina (the reverse of El Nino) events thought to follow a 1500-2000 year cycle. A late start and truncated breeding season should be expected during an El Nino event. Good breeding seasons may be predicted when La Nina event dominates the weather pattern of the Australian continent.

Weather patterns are believed to follow extremely long cycles (in the order of centuries rather than decades) and the breeding success and subsequent numbers of Gouldians seen in the wild will also fluctuate over an equally long period. This fact may explain the different observations regarding breeding patterns and fluctuations in numbers recorded by researchers.

Mr. Mobbs (1988) states: "(In Nature) Gouldian finches breed during the second half of the wet season (from approximately January to April). The first part of the wet season begins between November and December (last month of spring and first month of summer in Australia)."

Summer grasses respond to the first part of the wet season with second half rains providing the ideal time for the Gouldians to breed across their range.

Mr. Fidler (1989) comments, "The rain causes a dramatic change in the vegetation. The whole area springs to life as seeds that have been lying dormant for many months germinate and grow rapidly in the wet, warm soil. There is also an explosion of animal life. Insects, including mosquitoes and flying termites become abundant. This is a time of abundant food and the one during which most of Gouldians breed."

"It is possible (Pizzey and Knight 1997) that breeding may continue throughout winter (until September)" if food supplies persist as they are protected from cold autumn nights by nesting inside hollows of trees. Furthermore, winter night-time temperatures are mild and frosts are uncommon in the sheltered inland woodland and coastal scrubland they inhabit. Gouldians kept in captivity possess the same ability to breed in winter but require protection from the cold. Mutations, however, are weak and should not be permitted to breed in cold winters unless they are provided with artificial heating.

Breeding In Nature
Stony outcrops in sheltered savannah woodlands of north-western Australia support small stands of Salmon Gums (Western Australia) and Snappy Gums (Northern Territory), which provide perfect hollows for Gouldian nests. This habitat also provides small catchments of water that may persist for some time. Perennial grasslands form an important under-story layer to the eucalypt copses and are situated on the sides of shallow rocky gullies creating small catchment areas after rain. This is a perfect colony-breeding habitat for Gouldians, where in good seasons several pairs may share the same nesting tree. In dry seasons, Gouldians migrate in a north easterly direction to savannah scrublands closer to the coast, where mulga replaces eucalypts and termite mounds have been reportedly used as nest sites.

Gouldians respond to seasonal rain with cocks being the first to respond sexually followed quickly by the hens. The cock bird sings incessantly, attracting the hen, which leads to the formation of breeding pairs. Soon afterwards the cock chases the hen in search of a nesting site.

Hens accept the cock and allow mating only after an appropriate nest site has been located. Mating usually takes place inside the hollow rather than in the open. Gouldians do not make a nest but lay eggs directly into the log. Incubation does not normally commence until the final egg of the clutch has been laid. Both the cock and hen spend the daylight hours in the nest together whilst the eggs are being laid and roost outside the nest at night until the clutch is complete. They then take turns incubating the eggs with the hen spending the majority of the time on the eggs.

Incubation takes 14-16 days, the variation depending upon ambient temperatures and time spent away from incubation duties. Gouldians are not "tight" sitters, leaving the nest when temperatures are high. Hatching becomes obvious when the parents are seen to change shifts more often. Brooding stops when the chicks are 12-14 days old, leaving them to keep themselves warm. They remain very quiet in the nest until they are ready to leave the nest. Fledging (leave the nest) occurs at 25 days of age with the parents feeding the young until they are fully weaned at 5-6 weeks of age. The egg-laying interval in the wild can be as short as 8 weeks in very good seasons. As the next clutch is laid, about 6-8 weeks after the first clutch, the independent young are chased away by both parents. This is a time of hardship for young Gouldians in the wild and in captivity.

Moult in Nature
For Gouldians there is a special relationship between the moult and breeding behaviour with the moult priming them into breeding condition.

Most seed eating birds moult immediately after their breeding season. Gouldians experience a short, partial moult at the conclusion of breeding, replacing head and one or two flight feathers. The reason for this partial moult remains uncertain. It may be the result of hormonal influences, a remnant phenomenon of the ancestral moult pattern that occurs in many species at the conclusion of breeding. It may also represent a moult of old feathers not replaced during the previous annual moult due to breeding activity or drought. Whatever the reason, the short partial moult of head and wing feathers does not represent the main moult that occurs in spring.

The Gouldian Finch shares a similar annual pattern of moult (i.e. the once a year growth of new feathers that replaces the majority of old feathers) to the Budgerigar. They differ only in respect of the time of the moult. Gouldians have a spring time moult whereas Budgerigars have a summer moult. Importantly, both species moult prior to, rather than at the conclusion of the breeding season.

The spring moult cycle of Gouldians prepares them for a summer-autumn breeding pattern. A summer moult prepares Budgerigars for autumn breeding.

Both Budgerigars and Gouldians respond sexually to good summer rainfall. The more sedentary Gouldian is however less of an opportunistic breeder than the Budgerigar. The Gouldian Finch has a restricted although potentially long breeding season. Its length is restricted by the availability of food and permanent water. Under good conditions they have been reported (Pizzey & Knight 1997) to breed from December until September. In a "normal" season breeding ends by June.

Milton Lewis (Webpage: 2001) states that "the moult in the wild Gouldian begins at the end of the dry season (September-October) with some variation occurring between adults and juveniles. In general, most wild Goudians have completed the wing moult by late October and the body moult is finished by mid-December. There is however variation with some individuals taking longer to complete the moult". Tidemann (Emu. 94(1). 1994) states: "The Gouldian Finch began to moult after its breeding season (usually early February until October)."

The moult is a significant occasion for Gouldians and appears to be intimately related to their breeding cycle. In northern Australia, juvenile and adult Gouldians start to moult in spring, a time when food resources are often limited. In Nature the moult is usually completed by mid to late December. Supply of seeding grasses is necessary as the moult is an energy sapping process. The start of the moult may be delayed and its extent retarded by drought. During normal seasons the moult should have concluded by the end of December to coincide with the imminent start of breeding. Milton Lewis states "they begin breeding in February a month or so after the completion of the moult".

The moult in Gouldians starts two or three months before, but follows the same pattern as that of the wild Budgerigar (Melopsittacus undulatus). In good seasons, the wild Budgerigar starts its moult in December (the beginning of summer) and concludes the process by March (the beginning of autumn). March is the most favoured time for Budgerigars to breed in the desert regions of northern Australia. Under more adverse dry conditions, Budgerigars moult in a continuous pattern similar to the Zebra Finch who shares its nomadic ways and extensive desert habitat.

It is possible but unlikely that Gouldians may also fall into this opportunistic, intermittent but continuing moult pattern because prolonged drought is less likely throughout their breeding habitat. The ability of wild Budgerigars to adjust their moult to a more continuous pattern during droughts makes it difficult to predict when the moult of aviary Budgerigars should begin across the many different climatic regions of Australia, and throughout the world. Breeding strategies for aviary Budgerigars are consequently more difficult to plan because of the unpredictability of their moult.

The wild Gouldian is more sedentary and less nomadic across its range than the Budgerigar and its moult pattern can be more clearly defined, enabling enthusiasts to plan their breeding strategies more precisely. Spring is the natural time for Gouldians to moult. For continuing health and breeding success in captive Gouldians, breeding must not overlap the natural time for the moult.

Copyright © 2009 Rob Marshall, All Rights Reserved.