Cockroaches
Advice leaflet about Cockroaches
Often confused with black beetles from the garden, cockroaches are distinguished by their very long whip-like antennae, flat oval bodies and rapid jerky running about.
The adult small brown German cockroach is 10 50 15mm long, and the Common or Oriental cockroach is 20 to 24mm long.
They are rarely able to survive out doors in the British climate but thrive around the heating ducts and boiler rooms of large centrally heated buildings, in hospitals, bakeries, hotel and restaurant kitchens, laundries and blocks of flats. They cluster around pipes, stoves and sinks, especially in humid areas.
Significance
Cockroaches are potential vectors of diseases such as dysentery, gastro-enteritis, typhoid and poliomyelitis. Their diet is omnivorous and includes fermenting substances, soiled septic dressings, hair, leather, parchments, wallpaper, faeces and food for human consumption. Cockroaches and their faeces may cause allergic reactions especially amongst sensitive individuals e.g. asthmatics. Exposure may result from ingestion or through the inhalation of materials derived from cockroaches in airborne dust. In addition, food may be tainted with the characteristic smell of the cockroach, which is produced by faeces and salivary/abdominal gland secretions, or by the dead insects.
Life Cycle
Oriental cockroach
The female produces 5 egg capsules at monthly intervals. The thick-walled resistant capsules, 12mm in length, each contain up to 16 eggs and are cemented to the substrate or dropped in the vicinity of a food supply. This may then be covered over with debris. Nymphs emerge 6-12 weeks later and progress through 7-10 moults before reaching maturity, a process that takes 10 months to 2 years depending upon temperature and food supply. With each successive moult the wings, antennae and cerci (paired appendages located at the tip of the abdomen) develop and the nymph becomes progressively more like the adult. Adults live approximately 4.5 months at 25C.
German cockroach
The female of this species produces 4-8 egg capsules at approximately 1-month intervals. Each thick-walled resistant capsule is 6mm long and contains up to 30 eggs. Efforts are made to conceal the capsules near a food source, where the nymphs will hatch and pass through 5-7 moults before reaching maturity. At a temperature of 25C maturity is reached in 3.5 months, but this time can be profoundly influenced by temperature. Adults live approximately 8.5 months at 25C. The German cockroach is particularly successful for the following reason:
- A large number of eggs per capsule.
- The female protects the egg capsule by carrying it until just before hatching.
- Short development period to hatching and maturity.
- Small size therefore readily conceals itself.
Control of Infestation
a) Hygiene/management
A high standard of hygiene is important in the control of cockroaches and involves the following components:
- Deny access to food and water. This will increase cockroach activity and directed movement improving the opportunity for the insects to encounter insecticides.
- Deny access to harbourages in buildings or equipment that would otherwise provide hiding places, a means of gaining access and dispersing and breeding sites.
- Ease of cleaning. Buildings and equipment should be designed to minimise the accumulation of debris and facilitate ease of cleaning.
- Surveillance of incoming materials including packages and laundry.
b) Insecticidal control
Surface Sprays (Crawling Insect)
Effective treatment depends upon the selection and thorough application of a suitable insecticide. Many insects and egg cases are well hidden; therefore the insecticide must be placed at and around these harbourages and maintained over the developmental period of the particular species. To control an infestation the insecticide should ideally persist until all egg cases have hatched but continued immigration may demand routine treatments.
Do the Solihull Council Offer a Service for the Treatment of Cockroaches?
If you would prefer a Pest Control Officer from the Public Health Department to visit and treat for cockoaches within the property, then please telephone Solihull Connect on 0121 704 8000 to arrange an appointment. However, a charge is made for this visit, but it is not possible to guarantee 100% eradication.
We accept the following credit/debit cards when booking the appointment (please have these details ready): VISA, VISA DELTA, MATERCARD, SWITCH and SOLO