Oriental Cockroaches - Biology & Control

Oriental Cockroach (Blatta orientalis)

Origins and distribution

Found worldwide and throughout the UK.


Oriental cockroaches are about 17 – 30 mm in length and are shiny dark brown to black in colour. They have long flexible antennae with their head is tucked under the pronotum with well-developed spiny legs.


Egg cases (ootheca) contain about 16 eggs, which are carried by the female on the rear of her abdomen for 6 – 12 weeks, dependent upon temperature and deposited just before hatching.  Nymphs go through 7 – 10 moulting stages before reaching maturity, which takes about 6 – 18 months. Adults are winged, the males having longer wings but cannot fly in the UK and live for an average of 6 months.


Primarily nocturnal and prefer warm conditions in buildings, but can tolerate cold conditions. They have been found indoors in buildings such as restaurants, shops, hospitals and office blocks. They can also be found in refuse tips, drain systems and outdoors near buildings. We have experienced infestations in roof areas where bird guano has accumulated.

Signs of activity

  • Black faecal marks or spotting around the harbourage area.
  • Shed moulted skins.
  • Empty ootheca (egg cases).
  • Particular smell from their faecal deposits, associated with large numbers.


Oriental cockroaches can become a serious pest in buildings where they are able to harbour in the fabric of the building. They are known to carry various human disease organisms and cause contamination and tainting of foodstuffs.

How we control Oriental Cockroaches

Oriental cockroaches are generally controlled by the placement of gel bait, which acts as a stomach poison which starts killing the insects within hours after ingestion. The bait formulation also has the ability to disrupt the eggs if being carried by the female at the time of poisoning. Oriental cockroaches are scavengers and cannibalistic in nature and this habit of scavenging on another dead Oriental cockroach that has been poisoned acts as a domino effect with secondary poisoning occurring.

The gel bait is applied to various cracks, crevices, around pipes and where they harbour along with insect monitors (glue traps) that attract them in to be caught. This helps as a monitoring tool and establishing numbers, areas of activity and when riddance has been achieved. Depending upon the environment and legislation requirements regular routine maintenance or service visits may be necessary. We can tailor our service to customer needs.

Bookings & Enquiries

If you require any advice or a no obligation quote for our Insect Pest Control Services, please feel free to contact us...

0800 056 8834

Call today for a Free No Obligation Quotation on 0800 056 8834