Current locust situation

The overall locust population likely remained at low to medium levels across inland eastern Australia with a moderate decrease in the Central West district of New South Wales but slight increase likely in some parts of inland in February. Surveys conducted from mid-February identified frequent medium-density adults remained in the Quambone-Coonamble-Baradine-Gulargambone-Collie areas with occasional nymphs detected. The decrease of adult population may be partially attributed to westward migration and dispersal. Some medium-density adults were identified in Urana, Tibooburra, and Broken Hill areas of NSW with only low-density nymphs observed. Several medium-density adults were also identified in the Burra-Hawker areas of South Australia. NSW Local Land Services received and assessed a half-dozen reports of locust nymph and adult activity from the Central West district in February with some landowner ground control undertaken. No locust captures were recorded by any light traps in Dulkaninna of South Australia, Fowlers Gap and White Cliffs of NSW, and Thargomindah of Queensland for February. The UNSW insect monitoring radar in Hay was still not accessible due to the disruption of Telstra mobile network upgrade. No surveys were conducted in other parts of the inland eastern Australia, nor any locust reports received.

Most habitats in the arid/semi-arid interior of eastern Australia, where nil–10 mm of rainfall was received, remained unfavourable for locust breeding and became even drier during February. The northeastern part of inland in Queensland recorded 50–250 mm of rainfall. February rainfall totals were from very much below average to average levels over much of the inland with the northeastern part at above average to very much above levels. February temperatures were above average to very much above average levels (1–4 degrees warmer) over much of arid interior with the northeastern part below average levels (1–2 degrees cooler). With the forecast for above average rainfall for March and April and warmer temperatures, localised breeding is likely to continue under favourable habitat conditions, and a moderate increase of locust populations is possible in some parts of inland eastern Australia. However, some eggs may enter diapause for overwintering.

The overall outlook is for low-medium density populations across inland eastern Australia, with localised high densities of nymphs developing possibly in parts of central west NSW and inland Queensland. Migration may occur under favourable weather conditions resulting a general spread of the locust population further into the arid/semi-arid interior. It is likely that some small locust bands will develop from untreated populations or aggregated populations after migration/dispersal into favourable inland areas that received heavy rainfall from early March onwards.

There is a low likelihood of widespread infestations developing during autumn.

The overall population likely remained at low levels across inland eastern Australia with some localised medium-density populations in parts that received heavy rainfall. Surveys conducted since mid-February identified some Isolated-Numerous density adults in northern New South Wales with occasional Present-density nymphs detected. Some Isolated-Scattered density adults were also detected in South Australia. No capture in February was recorded by any of light traps in Thargomindah of Queensland, White Cliffs and Fowlers Gap of New South Wales, and Dulkaninna of South Australia. With heavy rainfall in some parts of Queensland and the forecast for above average rainfall for March and April, habitat conditions should improve, and breeding is likely to continue under favourable habitat conditions. Localised high-density nymph populations may develop in some areas of Central West and North West Queensland.

There is a low risk of a widespread infestation. Though, a general increase in numbers is likely to continue with forecast rainfall in favourable habitats during autumn.

The overall population likely remained at very low levels across inland eastern Australia. Surveys conducted since mid-February did not identify any locusts in New South Wales or South Australia. With heavy rainfall during February over some parts of the traditional locust habitats in Queensland and NSW and the forecast above average rainfall for March and April, localised breeding is likely to continue under favourable habitats. High-density populations are unlikely to result from the current very low background population levels.

There is a very low risk of a widespread infestation developing during autumn.