Distribution and abundance of the Asian paper wasp <i>Polistes chinensis antennalis</i> Perez and the Australian paper wasp <i>P. humilis</i> (Fab.) (Hymenoptera: Vespidae) in New Zealand

Abstract

Abstract Between 1987 and 1991, nearly 1500 samples of wasps were collected by the public after two national publicity campaigns. The Asian paper wasp (Polistes chinensis antennalis) arrived in 1979 and by 1990 was widespread throughout the upper North Island and present as far south as Lower Hutt and Nelson. It had also reached various islands near the coast of Northland and Auckland. P. c. antennalis populations increased the most between 1987 and 1990 in the central North Island. The Australian paper wasp (P. humilis) arrived in the 1880s and its distribution did not change between 1987 and 1991. It was still restricted to the upper North Island, apart from one record from Manawatu. It had not been displaced by P. c. antennalis. Most paper wasps were collected from urban habitats. A survey of natural habitats in Northland showed that P. c. antennalis also reached high population densities in open warm shrublands, flax swamps, and salt meadows. Paper wasps were rarely collected at altitudes above 100 m a.s.l. P. c. antennalis appeared in the samples earlier in the season than P. humilis, and both were most abundant during March and April. High populations of P. c. antennalis have increased the danger of stings to people by paper wasps, the predation of indigenous invertebrates, and also the beneficial reduction of lepidopteran pests in gardens.