The Mallee fowl (Leipoa ocellata) is a ground-dwelling bird that is native to Australia. It inhabits semi-arid mallee scrublands and is well-known for its unique nesting behaviour, where it builds large mounds of vegetation and soil to incubate its eggs.
The Mallee fowl is a stocky bird with cryptic plumage that provides camouflage in its habitat. Its most distinguishing feature is the large, flattened tail with distinctive barred feathers. Other notable features include its short, thick neck, large feet, and long toes adapted for scratching.
Mallee fowl belong to the family Megapodiidae, which contains birds known as “mound-builders”. Instead of incubating their eggs with body heat, megapodes use environmental heat sources like the sun or decomposing vegetation to warm their eggs inside nest mounds.
What does a Mallee fowl look like?
The Mallee fowl is a medium to large ground-dwelling bird, growing up to 65 cm long and weighing 700-1500 g. Here are some of its key identifying features:
- Stocky body shape with a small head, short thick neck, large feet and flattened tail
- Sandy brown and grey mottled plumage provides camouflage in dry scrublands
- Distinctive barred pattern on long tail feathers
- Yellowish or reddish wattles around eyes and throat
- Stout grey-black bill with a horn-like protrusion above the nostrils
- Thick strong legs with large feet and long toes suited for scratching
- Sexes similar but males are slightly larger on average
The cryptic plumage pattern allows the Mallee fowl to blend into its scrubland habitat. When threatened, it can freeze motionless with its neck extended to look like a broken branch. The barring on the tail breaks up its outline so it resembles foliage.
Where does the Mallee fowl live?
The Mallee fowl is endemic to Australia and is found only in semi-arid mallee scrublands. Mallee is an Aboriginal term for the multi-stemmed, low-growing eucalyptus trees that dominate these ecosystems.
The range stretches from the Eyre Peninsula and Murraylands of South Australia north through western Victoria, inland New South Wales and to south-western Queensland. Isolated populations also occur in the Kimberley region of Western Australia.
Within mallee habitats, Mallee fowl prefer areas with a sandy soil type and plenty of leaf litter. The litter is incorporated into the nest mounds and provides nutrients as it decomposes.
Mallee fowl habitat range in Australia:
- South Australia – Murraylands, Eyre Peninsula, Yorke Peninsula
- Victoria – Murray Sunset National Park, Wyperfeld National Park
- New South Wales – Riverina region, Murray-Darling basin
- Queensland – south-western corner
- Western Australia – isolated populations in Kimberley
The total occupied range is estimated to cover an area of over 600,000 km2. However, mallee habitats have declined by over 90% since European settlement. This has led to a significant contraction of the Mallee fowl’s distribution.
What does the Mallee fowl eat?
The Mallee fowl is an omnivore and consumes a varied diet. Their foraging behaviour typically involves scratching leaf litter to uncover food items. Their diet includes:
- Invertebrates – ants, beetles, caterpillars, insects, spiders, worms
- Seeds and fruits – native berries, Acacia and Banksia seeds
- Herbs, flowers, roots, tubers
- Fungi
The strong legs and large feet with long talons are adapted for powerful scratching of the ground litter. The nostrils have horn-like protections to prevent invertebrates from crawling in while foraging.
Moisture obtained from food enables Mallee fowl to survive without drinking water. They obtain any extra needed water from dew and rain collected in their mound nests.
| Food source | Examples |
|---|---|
| Invertebrates | Ants, beetles, caterpillars, spiders, worms |
| Seeds | Acacia, Banksia |
| Fruits | Native berries |
| Herbs/Roots | Tubers, flowers |
| Other | Fungi |
How does the Mallee fowl build its nest?
The most unique feature of the Mallee fowl is the large nesting mounds it constructs to incubate its eggs. Building these massive mounds is a labour intensive process.
Key facts about Mallee fowl nests:
- Diameter up to 5 metres and height up to 2 metres
- Constructed from sand, soil and leaf litter
- Litter decomposes and produces heat for incubating eggs
- Temperatures maintained at 33-36°C throughout incubation
- May take 90 days for pair to build the nest mound
- Maintained and reused annually with new litter added
Nest building begins around April or May. The male and female work together gathering material and excavating a pit in the centre. This is filled with layers of sand, soil and most importantly, leaf litter.
The litter provides insulation and generates heat as it decomposes. Temperature sensors in the female Mallee fowl’s beak enable her to meticulously maintain incubation temperatures. More material is added or removed as needed.
A large mound may contain over 500 kg of material and takes around 90 days to construct. The mounds are reused for multiple years, with new organic litter continually added. Some active nests may be over 40 years old.
How does the Mallee fowl reproduce?
Here is an overview of the Mallee fowl’s unique reproductive behaviour:
- Mound preparation – Between April-May, nest mounds are built or restored.
- Egg laying – Typically August-October, the female lays between 8-24 eggs within the nest.
- Incubation – Eggs incubated by heat of decomposing litter for around 60 days.
- Hatching – Chicks independently dig themselves out of the mound in November-January.
- Development – Chicks are fully independent, parents provide no further care.
Key facts about Mallee fowl reproduction:
- No pair bonds, males may mate with multiple females.
- Eggs are large, about 10-15% of female’s body weight.
- Eggs laid at intervals of 4-10 days for a total clutch of 8-24.
- Incubation temperature maintained at 33-36°C by the female.
- Hatching success around 80% in ideal conditions.
After the physically demanding mound building and egg laying, the adult Mallee fowl play no further role in rearing the chicks. The young must dig out of the mound and immediately fend for themselves.
What threats face the Mallee fowl?
Once a common sight in mallee scrublands, Mallee fowl numbers have declined drastically since European settlement. Ongoing threats contributing to its endangered conservation status include:
- Habitat loss – Over 90% of mallee habitat cleared for agriculture.
- Predators – Foxes and feral cats. Chicks especially vulnerable.
- Grazing – Rabbits, sheep and cattle degrade habitat.
- Fire – Too frequent fires can disrupt breeding.
- Climate change – Projected to worsen impacts of drought and heatwaves.
The total Mallee fowl population is estimated to have declined from 1 million to less than 100,000 mature individuals. Conservation efforts focus on habitat restoration and predator control in national parks and reserves.
Mallee fowl conservation status:
| Authority | Status |
|---|---|
| IUCN Red List | Endangered |
| EPBC Act | Vulnerable |
| SA, Victoria | Threatened |
| NSW | Critically endangered |
Conclusion
In summary, the Mallee fowl is a uniquely adapted Australian bird that builds impressive nesting mounds to incubate its eggs. This remarkable breeding strategy enables it to thrive in the harsh semi-arid conditions. However, extensive habitat loss over the past two centuries has led to a serious decline, and the Mallee fowl faces an uncertain future unless ongoing conservation efforts can ensure the survival of this iconic species. Protecting remaining mallee scrublands will give the Mallee fowl its best chance.
