Global Warming and Pests 

Kiwicare has noticed a southward spread of some insect pests over recent years. This is, perhaps, associated with warming temperatures as well as a natural spread of introduced pest species. Ten years ago, some insect pests were very uncommon south of Christchurch. It was thought that conditions, particularly winter cold, would prevent the establishment of pest ants, cockroaches and others in southerly regions. At that time, ants such as Darwin and Argentine ants were beginning to establish in Christchurch, but it was thought they would be unlikely to move further south. These ants have now been reported as pests in Invercargill.

Examples:

Ants

There has been a significant increase in visits from southern regions as compared to the general increase over the years. We now get website visits and enquiries from cities such as Invercargill, Queenstown, Dunedin and Timaru. Five years ago, we would not have had enquiries regarding ants from these cities. In 2018 website page visits from these cities were up 62% on 2017 this compares to an increase of 19% for all New Zealand for the same period.

Cockroaches

There has been a significant increase in visits from southern regions as compared to the general increase over the years. We now get website visits and enquiries from cities such as Invercargill, Queenstown, Dunedin and Timaru. Five years ago, we would not have had enquiries regarding cockroaches from these cities. In 2018 website page visits from these cities were up 6% on 2017 this compares to a decrease of 1% for all New Zealand for the same period.

Carpet Beetle

There has been a significant increase in visits from southern regions as compared to the general increase over the years. We now get more website visits and enquiries from south of Christchurch. In 2018 website page visits from these cities were up 70% on 2017 this compares to a decrease of 13% for all New Zealand for the same period.

David Brittain
Kiwicare