(Blatta orientalis)
Oriental Cockroach


Primarily nocturnal, a pest of warm environments but tolerant of colder conditions. Nymphs and adults cluster in groups in harbourages when inactive attracted by aggregation pheromone. Forage on wide range of foods but need access to free water. Found indoors in heated buildings, underground heating ducts and also in drains, refuse tips and outdoors near buildings. May even survive winter outside in protected environments but will not breed below 10°C. Climbs rough surfaces and may reach upper floors via vertical ducts, lifts. Does not tolerate extremely hot and dry conditions.


Egg - nymph - adult. Eggs - in ootheca (case) about 5 per female each containing average 16 eggs, laid at intervals. Deposited when fully formed in harbourage. Incubation period 6-12 weeks, longer if cool. Nymph - 7-10 moults taking from 6-18 months to reach maturity. Live and feed with adults. Adults - dark brown/black, robust living up to 6 months. Partial wings or wing buds, incapable of flight.


Serious pest in heated buildings such as hotels, laundries, institutions and multi-occupation dwellings, particularly in large urban areas. Can carry disease organisms.


Application of residual insecticide to all known harbourages, flooring, walls, cracks and crevices etc. Only to be undertaken by qualified technicians.

Interesting facts

A cockroach has the ability to survive having its head decapitated. It can remain alive an average of 2 weeks or even longer. Eventually it will die due to dehydration.