“The mere mention of cockroaches brings about a strong reaction in many people. However, the fast moving, shiny, black or brown cockroaches commonly encountered by people in their homes are almost never native New Zealand cockroaches, but introduced pests.” New Zealand Museum
The native Cockroach rarely, if ever, ventures into houses. They prefer to forage among the vegetation, leaf litter and soil in undisturbed habitats.
Cockroaches are a very ancient group of invertebrates, and can eat almost anything. Over the course of a year some female cockroaches can produce over 20,000 young. Their sheer numbers and indiscriminate feeding habits mean they may spread disease-causing organisms, and they can cause strong allergic reactions in some people. Many introduced species carry bacteria such as Salmonella, which they can pass to humans via their saliva and faeces.
The introduced species can often be found in sewers and around garbage, from where they can convey contaminated material into dwellings. Cockroaches are found all over the world. There are more than 3,500 species of cockroach. The most common pest varieties in New Zealand include the German, American and Oriental cockroaches. American cockroaches are large and black. German cockroaches are smaller and brown. Oriental cockroaches are medium sized and dark brown to black in colour.
The Life Cycle of a Cockroach:
A female cockroach lays between 10 and 40 eggs at a time within a protective case called an ootheca. The ootheca may be carried for some time by the female before being deposited on the ground or buried in the soil.
The female can lay on average around 30 batches of eggs in her lifetime.
Hatched young look the same as adult cockroaches, but smaller and without wings.
Cockroaches thrive in warm, humid conditions.
Depending on the conditions and type, a cockroach can live for up to 12 months.
Where to find Cockroaches in Your Home:
Kitchens and food preparation areas, especially where they have access to water.
In any deep crack, in confined spaces, such as under the refrigerator, in the pantry or underneath magazines, newspapers or cardboard boxes.
They particularly enjoy electrical appliances where running the appliance generates warmth.
In drains, grease traps, and around kitchen sinks.
In the spaces between the bottom of kitchen cupboards and the floor.