Australia has three species of mound-building birds, and by far the most well-known and widely distributed is the Australian brush-turkey.
Mound-building birds, which also occur throughout PNG, SE Asia and the S Pacific islands, rely on natural thermal processes to incubate their eggs once they are buried in the mound.
In the case of Australian brush-turkeys, the mound is constructed by the male out of leaf litter and can be over 4m in diameter and over 1m in height. The male senses and adjusts the temperature of the mound to keep it around 34 degrees Celsius, by either adding or removing leaf litter, which creates the heat as it composts. Females can lay around 20 eggs, and sometimes multiple females will lay in one mound.
When the chicks hatch, they are highly developed and don’t receive any support from their parents. They are fully feathered and highly mobile and are able to forage for food themselves. As with the Masked lapwings which we looked at recently, being this well-advanced gives them a higher chance of survival as a ground-based bird.
Within the last twenty or so years, a remarkable behavioural adaptation has occurred with Australian brush-turkeys – they have adapted extremely effectively to urban environments. Originally found on the east coast from Sydney to Cape York, they favoured rainforest and even inland woodlands like brigalow, but they are now found widely and very successfully in urban environments. They have shifted their diet to now include human garbage, and their habit of roosting safely in very high trees protects them at night. For a medium to large sized bird the success of their adaptation to human environments is surely only matched by that of the Australian white ibis.
This article first appeared in the High Country Herald 11th of December 2023