Story: Introduced land birds
Page 6 – Australian magpies
Introduction and distribution
Australian magpies (Gymnorhina tibicen) were introduced in the 1860s and 1870s in Canterbury, Otago, Auckland (Kawau Island), Hawke’s Bay and Wellington. They came from Victoria and Tasmania.
These populations expanded slowly, remaining separate for many years. The original Otago population has disappeared altogether, but magpies are now found over most of the country except the most densely forested regions, such as Fiordland, or the most open country, such as Central Otago.
Magpies reportedly peck away at power-line fittings, sometimes causing lines to short circuit and electrocuting themselves. They have been blamed for starting fires after catching alight and falling into dry vegetation in a ball of flames.
Magpies were introduced to control pasture pests, which is why they were protected until 1951.
Australian magpies have black heads and patchy black-and-white bodies. Their heavy bill is cream with a dark tip. They are about 350 grams in weight and 41 centimetres long.
In the past, there were thought to be two distinct Australian magpie species introduced – white-backed and black-backed. However, they are now known to be the same species.
Australian magpies eat a mix of plants and animals, including grass and clover seeds, invertebrates (grass grubs, caterpillars, worms, spiders, crickets, snails, flies), and some vertebrates and carrion. They often eat on the ground.
Impact on native birds
Magpies are reputed to reduce the number of native birds, particularly tūī and kererū. Magpies sometimes raid native birds’ nests for eggs and nestlings. They also mob or attack other birds – harriers in particular – and often kill smaller bird species in acts of territorial defence.
Magpies attack, and occasionally injure, humans and other animals that come within range of their nests during the breeding season.
The call of magpies evokes country life in New Zealand’s dry, eastern regions. In his poem ‘The magpies’, Denis Glover told a story of rural hope and despair against the backdrop of the ever-present magpie cry. His version of their call – ‘quardle oodle ardle wardle doodle’ – has become familiar to many.
Their nests, which they usually build in tall exotic trees, are often made of a mixture of natural and man-made fibres, such as fencing wire, pieces of string and broken china. They lay three to four eggs, but only one or two chicks are reared. Eggs are usually bluish-green with olive blotches.
Magpies are good mimics, repeating neighbourhood sounds such as barking dogs. They are sometimes kept as pets and taught to mimic words.