Magpies have a long breeding season which varies in different parts of the country; in northern parts of Australia they will breed between June and September, but not commence until August or September in cooler regions, and may continue until January in some alpine areas. The nest is a bowl-shaped structure made of sticks and lined with softer material such as grass and bark. Near human habitation, synthetic material may be incorporated. Nests are built exclusively by females and generally placed high up in a tree fork, often in an exposed position. The trees used are most commonly eucalypts, although a variety of other native trees as well as introduced pine, "Crataegus", and elm have been recorded. Other bird species, such as the yellow-rumped thornbill ("Acanthiza chrysorrhoa"), willie wagtail ("Rhipidura leucophrys"), southern whiteface ("Aphelocephala leucopsis"), and (less commonly) noisy miner ("Manorina melanocephala"), often nest in the same tree as the magpie. The first two species may even locate their nest directly beneath a magpie nest, while the diminutive striated pardalote ("Pardalotus striatus") has been known to make a burrow for breeding into the base of the magpie nest itself. These incursions are all tolerated by the magpies. The channel-billed cuckoo ("Scythrops novaehollandiae") is a notable brood parasite in eastern Australia; magpies will raise cuckoo young, which eventually outcompete the magpie nestlings.