Landholders in cropping areas are encouraged to take action now to control any locusts they find ahead of mid-December.
Patches of developing small hopper bands of Australian plague locust (Chortoicetes terminifera) have been detected by the Department of Primary Industries and Regions' (PIRSA) helicopter and ground surveillance teams in localised areas north of Hawker, north-east of Yunta, and on Upper Eyre Peninsula including the Gawler Ranges.
Until mid-December, locusts will continue to feed and develop through five juvenile/hopper stages ('instars') before reaching the adult stage. Juveniles/hoppers cannot fly but have wing buds that increase in size as they grow. Detailed information on the growth stages of locust nymphs can be found on the About locusts page of the Department for Agriculture, Fisheries and Forestry website.
Adults migrate in search of green feed, creating a potential threat to crops. In maturing cereal crops, locusts often feed on the remaining green part of the stem below the head, resulting in lopped grain heads.
Areas likely to see adults include the Mid and Upper North, Upper and Western Eyre Peninsula, and the SA Mallee. Adult locusts may move into some northern cropping areas where crops are close to maturity.
Landholders are responsible for locust control on their properties. PIRSA helps with control where there are large outbreaks (above 100 hectares) in pastoral areas to reduce overall populations. None of the hopper bands identified through surveillance have met the minimum target requirements for aerial spraying control by PIRSA; many of the surveyed sites had nil or low locust numbers.
Hopper bands should be sprayed directly with an Australian Pesticides and Veterinary Medicines Authority (APVMA) registered or permitted insecticide. Products containing synthetic pyrethroids, chlorpyrifos, or malathion, are available. See apvma.gov.au for more information; local chemical resellers and consultants can provide more specific chemical recommendations.
The ideal time to spray locusts is when they are around 2–3 weeks old, when they are more mobile and march and feed in bands. Hopper bands are usually a couple square metres or larger.
Any sightings of Australian plague locust bands should be reported either through the Exotic Plant Pest Hotline on 1800 084 881 or the Locust Locator form. For more information see Australian plague locusts.