Introduced sparrows turned pest, prompting bounties and poison in 19th-century New Zealand

In 1867 the Canterbury Acclimatisation Society released forty house sparrows, expecting them to feed on crop-eating insects. While the chicks initially consumed caterpillars and beetles, adult sparrows turned to grains and fruit, damaging wheat, barley and maize fields. Their prolific breeding, aided by abundant food, mild climate and few predators, caused their population to explode.

Within two decades, farmers and authorities organized “sparrow clubs” modeled on English groups, employing poisoned grain, shooting and financial incentives for sparrow eggs and heads. Bounties encouraged even schoolchildren to gather hundreds of thousands of eggs. The sparrow problem was part of a broader pattern of European birds introduced to New Zealand, many of which later required similar control measures.