Insect pests

German wasp (Vespula germanica). Photo: Bernie Kohl

There are many species of insect pest in New Zealand. They include species that affect the New Zealand economy such as the gypsy moth and the varroa mite and species that affect our indigenous biodiversity. Some examples are provided here:

Wasps

Four pest wasp species have been accidentally introduced to New Zealand. They are the Asian paper wasp, the Australian paper wasp and the German and common wasps. The German wasp was introduced with US aeroplane parts in the 1940s and the common wasp arrived only recently but is already widespread.

New Zealand has some of the highest densities of common and German wasps in the world since they have no natural predators here. They are especially problematic in beech forests where they consume honeydew which is produced by a native scale insect and is an important food for native birds, bats, insects and lizards. Wasps also prey on insects and have even been seen killing newly-hatched birds.

Argentine ants

Argentine ants (Linepithema humile) are one of the worlds most invasive and problematic ant species. They are aggressive and although they are not poisonous, they do bite people. Argentine ant colonies co-operate with each other and, over winter, can combine over winter into super-colonies. Argentine ants are small (2-3 mm long) and honey-brown in colour, while most other common household ants in New Zealand are black.

Argentine ants are highly active in searching for food and their trails are often five or more ants wide. Unlike most other ants, they climb trees to get to food sources. Argentine ants can have a massive impact on the natural environment. These threats include eliminating other species of ants, competing with birds and lizards for food such as insects and worms and displacing and killing native invertebrates. They are known from parts of Auckland and Northland, as well as Bay of Plenty, Hawkes Bay, Wellington, Nelson and Christchurch.

For more information go to:

 

This page last updated on 13 Dec 2012