Guide to the Cockroaches of Australia

Australian Cockroach Guide

Understanding the types of critters in your home can equip you better to curb infestations. If you have become aware of cockroaches, you might be wondering what kind of cockroaches you have.

Since different species thrive in different environments, it can be tricky to identify them correctly. The various Australian cockroach species tend to look similar, which often means smaller species are mistaken for young cockroaches when in actual fact, they’re a different type.

Cockroaches remain one of the most common critters that plague households. Their uncanny ability to remain undetected leaves only their droppings and brief glimpses of them, before they disappear, as evidence of their existence.

Cockroaches pose a legitimate health risk to humans. They spread dangerous bacteria via their back legs and their mouths. One of the best ways to keep cockroach populations to a minimum is to remove any food sources (like food scraps) and seal away water.

1.  German Cockroach

• Size and Shape

This cockroach is rather petite in comparison to other members of the cockroach family. It is usually less than 2 CM in length, reaching around 1.6 CM. It looks like the Asian cockroach ad probably one of the most widespread household pests. This cockroach does not fly, unlike the Asian cockroach which does.

• Breeding and life cycle

German cockroaches reproduce at prolific rates. In fact, they breed faster than any other domestic cockroach. Their short reproductive cycle means that babies are mature and ready to reproduce as soon as 50 days after hatching. This makes them very difficult to manage as a pest.

• Habitat

German cockroaches will stay out of sight and they prefer tight corners. This means that they are thigmotactic. They’re skilled at hiding, slipping into tiny cracks and crevices. They only come out at night when all the lights are off, which means most people are unaware that they have German cockroaches taking up residence in their homes.

• Food

The German cockroach will practice cannibalism when food is scarce. They are opportunistic feeders, seeking starchy and fatty foods. They thrive on human scraps and will even feed on household items like soap and other compounds we wouldn’t generally consider edible.

2.  Australian Cockroach

• Size and Shape

This tropical cockroach, the Australian cockroach (Periplaneta australasiae) is significantly larger than the German cockroach, measuring around 2.3 CM in length. They are generally brown in colour and pale or yellow towards the end (the tegmina).

• Breeding and life cycle

Like the other cockroach species, the Australian cockroach breeds fast. Females typically have around 25 eggs at a time and she will breed 20 – 30 times in her lifetime. That is around 750 babies per female!

• Habitat

This cockroach only survives in warm and moist conditions. During chilly months, they will seek warmth in human homes in order to thrive. This cockroach is common in areas of the USA, Africa, and Australia. Despite its misleading name, it probably doesn’t originate in Australia. You’ll find Australian cockroaches in the following areas around your home;

1. Drains
2. Greenhouses
3. Piles of firewood
4. Sinks
5. Toilets
6. Tree bark
7. Water pipes

• Food

Like most cockroach species, this insect is omnivorous, meaning it eats both plant matter and animal matter. It will seek out starchy and fatty foods.

3.  American Cockroach

• Size and Shape

These giants can reach lengths of up to 4 CM. They are a warm brown colour and the area behind the head tends to be a yellowish colour. They’re incredibly fast, they’re one of the quickest scuttling insects. They can avoid detection by darting out of sight incredibly quickly and disappearing into tiny cracks and crevices.

• Breeding and life cycle

Females can reproduce up to 150 babies in one lifetime. Their reproduction cycle lasts for as long as 600 days. The females have an egg case which protrudes from the abdomen. When the eggs are mature the mother deposits the egg case somewhere safe and the nymphs emerge, ready for the world.

• Habitat

Ideally, these cockroaches enjoy warm and moist conditions of around 29 °C. They will survive in hot dry conditions provided they can reach a water source. These cockroaches are common in basements, near sewers, between cracks in floorboards, under porches and in crawl spaces.

• Food

These cockroaches are famous for their love of fermented foods. They often eat dead and decaying matter. This makes them fond of beer, cheese, bread, leather and even the glue in book bindings.

4.  Oriental Cockroach

• Size and Shape

This cockroach is also known as a water bug, but its scientific name is Blatta orientalis. They’re generally just under 2 CM in length with glossy and dark colour.

The males and females look very different. The female has ornamental wings that are short but her body is broad. The male has longer wings which are also no-functional but a much thinner body.

• Breeding and life cycle

The females lay egg cases containing eggs in a safe space. These egg cases form within a day of fertilisation. They hatch between 42 and 81 days after the female deposits the eggs, depending on the temperature. In warm moist conditions, they hatch much sooner.

• Habitat

Their nickname “water bug” comes from the fact that these bugs require lots of moisture in order t survive. More than other cockroaches. They lurk in marshy conditions, near compost heaps and around decaying matter.

• Food

Oriental cockroaches prefer decaying plant matter in nature. That’s why they prefer to live near watery areas where trash and decaying food matter is readily available. They also crawl in sewer pipes and eat dirt and bacteria-ridden matter. It is important to keep these bugs out of your home.

Managing cockroaches and other pests

Insects, like cockroaches, and others pests like rats can be difficult to manage. Laying out bait and traps may not be enough. Unfortunately, unless you know how to seek out and identify these pests, you’re probably unaware of the extent of an infestation.

Spotting the off insect is the first sign that it’s time to get a pest controller in. From there, you can decide how you’d like to handle the situation.