Cockroaches come in many shapes, colours and sizes – in fact there are over 3,500 cockroach species around the world. In Australia there are four main types of cockroach. And whilst most people want to spend as little time as possible thinking about cockroaches, identifying which type of cockroach can help to eradicate this unhygienic pest. Every cockroach species has their own distinct set of characteristics to deal with and using the right types of pest control is important.
The four main varieties of cockroach that you may have seen around your house and garden are the Australian, German, American and Oriental cockroaches.
Australian cockroaches are a large winged species, which are brown in colour and measure about 3cm in length. They’re often mistaken for an American cockroach, but the Australian version is slightly smaller. It also has a yellow pattern on the thorax and similar streaks near the wings. Despite the name, this species originated in Asia and is common around the world in warmer climates including the southern United States. They can travel quickly and fit into small cracks and under doors, despite their fairly large size.
German cockroaches are the most common variety found in homes. Once again despite their name this species of cockroach actually originated in Africa. A smaller species, they measure about 1.3cm to 1.6cm long and range from tan to almost black in colour, with two dark parallel streaks running from the head to the base of their wings. Although winged, they cannot fly. The German cockroach scavenges and is particularly attracted to starch, sugary foods, grease and meat.
The German cockroach multiplies extremely quickly – from a single female a home could be infested by 100,000 cockroaches by the end of one year. They are a difficult pest to control not only because of their rapid breeding, but also because surface treatments can often be ineffective against them as they stay hidden as immature insects.
American cockroaches are another cockroach species introduced from Africa – estimated to have occurred in the 17th century. The American species is larger than the German cockroach and as such are easier to spot and exterminate. They are winged and prefer warmer climates, where they also can fly. They don’t reproduce as quickly as the German cockroaches, so they can be easier to eliminate. They’re the largest species of the common cockroach, growing to about 4cm in length and are reddish brown in colour, with a yellowish colouring on the body region behind the head.
Oriental cockroaches are about 1.6cm long, dark brown to black in colour and have wings. The female Oriental cockroach has very small wings whereas the male has longer wings. This species is also more attracted to light, prefers the outdoors and is often found in sewers, drains and in gardens. The Oriental cockroach moves more slowly than other species and prefer dark, moist places. They are often seen under mulch, leaf cover or other damp outside places