Locusts on your windscreen

Locusts belong to the same order of insects as grasshoppers, katydids and crickets - the Orthoptera which are readily identified by their large back legs which enable them to hop or jump.

The high yellow fat content of locusts make them hard to wash off your car windscreen!

Locusts are insects that can be devastating pests to agriculture due to their ability to develop very large populations and to form dense and highly mobile swarms. Each locust can eat its weight in plants each day.

Adult locust population levels increased throughout Victoria during March and isolated locusts were reported as far south as Melbourne. A number of small swarms were identified across northern Victoria and there are reports from the Bendigo and Shepparton areas. Most of these adult locusts are a result of flights into Victoria from NSW over the last two months from much heavier populations present in NSW. Autumn egg laying began in late March but hatchings will not occur until October. A serious infestation is likely during spring following significant immigrations during April.

Adults of the Australian plague locust can be distinguished from other species by the large dark spot on the tip of the hindwings and distinctive scarlet hindleg shanks. Adults measure 25-45 mm long, are able to fly and migrate and their body colour is variable (grey, brown or green).

What is the difference between a locust and a grasshopper?

Locusts and grasshoppers are similar in appearance - how they differ is in their behaviour. Locusts can exist in two different behavioural states (solitary and gregarious) whereas grasshoppers generally do not. When the population density is low, locusts behave as individuals, much like grasshoppers. However, when locust population density is high, individuals undergo physiological and behavioural changes, known as phase change, and they form into gregariously behaving bands of nymphs or swarms of adults.

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