Most people think of cockroaches as disease-carrying dirty pests, found in homes and backyards. In reality, however, Australia is home to approximately 450 different species of cockroaches, and only about five species are actually considered serious pests.
When we talk about the typical ‘Aussie Cockroach’, we are typically talking about the larger ones – the Common Shining Cockroach or the Australian Cockroach, or the smaller light brown ones – the German Cockroach.
The cockroach life cycle
A female cockroach can lay up to 40 eggs at a time and on average around 30 batches of eggs in her lifetime. A cockroach may live up to 12 months, although dependent on the conditions they live and the type of cockroach. As cold-blooded insects, cockroaches live and thrive in warm, humid climates. This is why homes and buildings in South East Queensland are specifically prone to infestations.
The cockroach’s habitat
Cockroaches are nocturnal creatures and therefore experts in hiding. They like to establish themselves wherever they can find reliable sources of food, water and shelter, which is quite often why you will find them scurrying across your kitchen bench at night, or across your bathroom floor to access water.
The larger cockroaches you will most likely be seeing in and around your home generally live in the outside garden area, they do not normally breed inside – which is an excellent thing! It is, unfortunately, the smaller German cockroaches, which will happily breed and feed inside your home. You will typically see these German cockroaches in restaurants and fast food areas and love warm areas such as ovens, refrigerator motors and kitchens.
Can cockroaches actually cause harm?
Cockroaches are not the most sanitary insects. They generally feed on garbage, breed in sewage and lay waste all over your kitchen benches. Although they do not produce any form of poison and have no ability to sting, they have been known to bite humans however this is extremely rare!
Do cockroaches carry and spread disease?
It is understood that cockroaches may be the carrier for a range of bacteria and pathogens including salmonella, staphylococcus and streptococcus. According to the World Health Organisation https://www.who.int/water_sanitation_health/resources/vector288to301.pdf, cockroaches are known or suspected carriers of the microorganisms that can cause diarrhoea, dysentery, cholera, leprosy, plague, typhoid fever and viral diseases, such as poliomyelitis. Although they would be considered the main cause of spreading these diseases, they do play a supplementary role and their presence can exacerbate allergies and asthma.
Like the household fly, the cockroach will eat virtually anything ranging from food spills on a kitchen floor to faecal matter. Ingested bacteria can survive in the cockroach’s digestive system, sometimes for months or even years, and are passed in its droppings. Cockroaches will vomit and defecate on food and it is thought that disease may be transmitted to humans when humans eat food contaminated by cockroaches.