The magpie-lark is generally a non-migratory species, although it may be partly migratory in some areas (2). Adults may join flocks of immature magpie-larks in autumn and winter, forming large flocks of up to 3,000 individuals. These birds frequently display communally, demonstrating incredible feats of acrobatic flying (3).
The magpie-lark is primarily a carnivorous species (4), feeding mostly on invertebrates such as insects, spiders, worms and crustaceans (2). However, small vertebrates, including reptiles and frogs, are also sometimes taken (3), and seeds are occasionally eaten (2). The magpie-lark is beneficial to humans as it feeds on pests, and in northern Australia it is known as a ‘stock inspector’, as it can often be seen perching on the backs of livestock, picking off ticks (3).
Feeding singly or in pairs, the magpie-lark mainly forages on open ground, including exposed tidal flats and urban lawns, opportunistically picking up food items or scratching at the ground to uncover prey. This species also uses a foraging technique known as ‘foot-trembling’ on very wet mud, which brings prey items to the surface. A very active species, the magpie-lark is constantly calling and fluttering about, and will sometimes take aerial prey during brief sallies into the air (2).
Breeding in the magpie-lark is related to rainfall (2), and usually begins after the onset of rain in the wet season (3). In southern Australia, breeding normally occurs from August through to February (4). Male magpie-larks advertise for mates at the beginning of the breeding season by making ‘pee-o-wit’ calls, and several males may compete for a single female. Once a female has chosen a male, the pair set up a territory (3), which is fiercely defended against other birds. The pair generally mate for life (3) (4), and often keep the same territory year on year (3).
In south-western Western Australia, nest building usually starts in July, with egg laying in August, whereas magpie-larks in south-eastern Australia do not begin nesting until late August, with egg laying in September (2). This species often nests near lakes or rivers (3), and the male and female magpie-lark both gather wet mud to construct the bowl-shaped nest (2) (4), which is built on a horizontal branch up to 20 metres above the ground (4). The magpie-lark uses its breast to mould the mud, reinforcing the nest walls with grass, feathers and horsehair (3), and lining the nest with soft vegetation and feathers (2) (4).
Each magpie-lark clutch contains between one and six eggs (2), although three to five is most common (3) (4). The eggs are incubated by both sexes (2) (3) (4) (5), for between 17 and 19 days (2). The chicks are cared for by both the male and female magpie-lark (2) (4) (5), and fledge at 19 to 23 days old (2). The young become independent approximately five weeks after fledging (2), and form flocks with other young birds (3). When conditions allow, second broods are commonly produced (2) (3) (4).
The magpie-lark first breeds at two years of age (2) (3), and has a lifespan of ten years or more (2).