The German cockroach is found widely throughout Europe and in Britain It is a pest of warm indoor environments. The adult is about 12-15 mm long with long antennae and long spiny legs. The area in front of the wings is yellowish / brown with two dark brown stripes.

Biology

The mated female cockroach produces a complicated egg-case called an ootheca which contains up to 30 eggs. This is carried by the adult until the young nymphal adults, after between2-4 weeks, burst through the seam of the casing.

The freshly hatched nymphs are pure white, but rapidly darken to a medium brown and undergo a variable number of skin moults. At each moult the insect grows slightly larger resembling a small adult.

The adult cockroaches emerge from the final nymphal stage between 2 and 6 months later and are sexually mature. They are gregarious insects and eventually produce sizeable population groups and these often produce a strong sour smell.

They are not active during the day, but emerge in the dark to forage for suitable food and water. Since they need a free water source for drinking they invariably hide during the day in the vicinity of taps, sinks, drains or other water sources. They are omnivorous and will scavenge on any form of organic material, including human waste products. Warm conditions of around 30c are needed for optimum breeding and although they are resistant to cold temperatures continuous exposure to frost is fatal.

Importance

The German cockroach is known to carry human disease organisms. Its habit of walking over and feeding on putrefying waste materials and then freely walking over food preparation areas, cutlery, crockery and human food enables the easy transmission of such organisms.

In addition to the above the unexpected rapid scurrying if insects when a light is turned on can be upsetting especially if the occupiers were unaware of the existence of an infestation.

Control

A systematic, integrated approach to cockroach control is essential. Firstly the extent of the infestation should be determined using sticky traps and the species identified. The treatment should then start at the periphery of the infested area , working inwards to the sources of infestation. Any treatment undertaken will require scrupulous attention to cleanliness with the removal of any food residues.

Unsound surfaces should be made good and any possible harbourage sites sealed.

The actual treatment and distribution of poison is a specialist activity and should be carried out by a specialist contractor.

The Council will charge to treat for cockroaches.