Cockroaches are common household pests in most parts of Aotearoa, with over 30 known species present, most of which are native bush varieties that feed on leaf detritus.
In Tasman, one accidentally introduced species of cockroach that has exploded in numbers in recent years is the Gisborne cockroach.
Native to Australia, where they are known as the ‘Eastern wood runner’ cockroach, these shiny, dark brown cockroaches have a distinctive cream-coloured stripe on either side of their thorax.
They were bestowed the name ‘Gisborne cockroach’ in honour of the place where they were first recorded in New Zealand, back in the 1960s.
Gisborne cockroaches prefer to stay outside under bark or wood chips, however they will come inside if it’s too wet or too hot.
In the Tasman District over the past few months, many residents have noticed a heightened presence in their homes.
While cockroaches are only a low-level health risk, some introduced species, such as German and American cockroaches, thrive in unhealthy environments and can transmit several diseases, such as dysentery, salmonella and diarrhoea. If cockroaches contaminate your food or the surfaces you use, you could become sick.
Fortunately, the Gisborne cockroach does not spread disease. They are often seen outside on building walls at night and can fit into tiny, confined spaces such as recesses in aluminium joinery.
A range of surface contact sprays containing the active ingredient Bifenthrin will provide good control of cockroaches (and ants) and can be purchased through most hardware stores.
For more information on insect control, check out the ‘controlling pest insect invaders guide (pdf 1.4 MB)’ or pick up a pamphlet at one of our service centres.