Port Macquarie Pest Control 02 65845536 Email pmqpestcontrol@gmail.com

                          Cockroaches

There are 428 species of cockroach in Australia and a number of introduced species have become pests. The two most significant pest cockroaches are the German cockroach and the American cockroach.

Cockroaches live and feed in unhygienic places such as sewers and drains, or feed on garbage that may be contaminated. These insects are cold-blooded and thrive in warm, humid conditions. This is why buildings in the northern parts of Australia are particularly prone to infestations.

However cockroaches will make their home wherever they find food, moisture and shelter.

 

Lifecycle


A population of cockroaches can build quickly if not kept in check. A female cockroach lays between 10 and 40 eggs at a time. On average, the female can lay around 30 batches of eggs in her lifetime. The hatched young look the same as adults, only smaller and without wings. Very small nymphs hatch from the egg capsule and then develop through a series of nymph stage to become adults. Depending on the conditions and type, a cockroach can live for up to 12 months. 

German cockroach
The German cockroach is the most common cockroach found in houses and apartments in Australia. Their small size means that human occupants, many of whom do not recognize early nymphal stages as cockroaches, initially tolerate them. 

Their rapid reproduction rate enables a few individuals to become a pest problem over one season. From an original female German cockroach there could be potentially more than 100,000 cockroaches in a home by the end of one year! 

German cockroaches are nocturnal and forage for food and water at night when they are less likely to be seen. In the daytime, they hide in cracks and crevices in cupboards and kitchen appliances and so are easily overlooked. You can find them around refrigerators, dishwashers, stoves, washers and dryers, and water heaters. They do not fly.
The German cockroach is the most difficult pest cockroach species to control.

American cockroach

The American cockroach is the largest of the pest species. It is red-brown, with fully developed wings that cover the abdomen, and it will fly in warm conditions. The American Cockroach has a great potential for producing offspring.

Because of the large size of both adults and nymphs, people are less tolerant of this species, and the cockroaches also find fewer places inside to hide in the daytime. When established in homes they are normally found in wall voids or behind cupboards, in underfloor areas or in roof spaces.

Normally they enter living rooms, kitchens and bathrooms when they are foraging for food and water. They are most associated with the areas around homes or buildings. Common areas where they are found include gardens, around garbage, inside drains and in outhouses such as sheds or garages.

American cockroaches can coexist with German Cockroaches with no negative effects on either cockroach population.

Brown-banded cockroach

A single brown-banded female cockroach has the potential to produce about 250 offspring. But, because of the longer time that it takes nymphs to grow into sexually mature adults, large populations are not produced as quickly as those of the German cockroach. In addition, because the egg cases are glued to objects in the environment soon after formation, they are susceptible to drying out, attack by fungi and other factors that contribute to produce a low hatch rate

This translates into a much lower potential for offspring production than for the German cockroach.
They are often found dispersed through the house behind picture frames and in light switches and furniture. Because they require less water than German cockroaches, they often survive in drier locations that are unsuitable for German cockroaches. They frequently occur in locations at eye-level or above such as in cabinets, around closet shelves, behind pictures, in warm areas near motors of refrigerators, electric clocks, timers and television sets. Other favourite habitats are around the braces of kitchen chairs and tables, around objects on the wall and in showers.

The oriental cockroach

found in the cooler areas of Australia. They are dark brown or black and may be found under floors, in sewers and drains, and around garden rubbish.

A single female oriental cockroach has a much lower potential for producing offspring than either the German or the brown-banded females.

 

They are more sensitive to lack of water than other cockroaches and like cool, damp locations. Look for oriental cockroaches in dark, damp basements, crawl spaces, areas between soil and the foundation, underneath sidewalks, in sewer pipes, floor drains and any other cool, moist place. Outside, they sometimes aggregate near or under garbage cans.

Economic and health impacts of cockroaches
Cockroaches are a health hazard. They carry bacteria on their bodies from sewers, drains and garbage areas and then transmit it to you and your family by visiting your kitchen and bathroom areas. Feeding in such areas as sewers, drains and garbage areas brings them in contact with disease organisms including salmonella and other organisms associated with dysentery, typhoid, hepatitis and tuberculosis.

Ingested bacteria can survive in the cockroach's digestive system, sometimes for months or even years, and are passed in its droppings. It is thought that disease is then transmitted to humans when they eat cockroach droppings on contaminated food.

Cockroach allergies and asthma
People can become allergic to cockroaches and their faeces. This allergic reaction is a worldwide phenomenon, with sensitivity to cockroaches ranging from 23–60% of the population tested. Cockroach allergens are present mostly in settled dust, rather than air, as the particles are large and do not remain airborne unless disturbed. There seems to be a particular association between cockroach allergens and asthma but they can also cause rhinitis and dermatitis. The allergens are potent sensitisers of children and exposure to cockroach allergens early in life has been found to be a predictor for the development of asthma.