Current Locust Situation and News
Locust situation in November 2009
This page summarises the known distribution of locusts during October 2009 and provides a brief outlook to mid-December 2009. The next Locust Bulletin will be published in December 2009.
- Australian Plague Locust Situation
- Forecast development dates
- Spur-throated Locust Situation
- Migratory Locust Situation
Australian Plague Locust (Chortoicetes terminifera)
The infestation in Central West New South Wales continued to develop during October and a number of swarms were reported in the Coonamble area at the end of the month. Hopper bands were identified in many parts of the Central West Livestock Health and Pest Authority (LHPA) throughout October, and in adjacent parts of Central North and Lachlan LHPA areas. Extended hatchings during September resulted in a range of nymphal stages and a proportion of fledgling adults from mid-October. Landholders and LHPA staff continued ground control of hopper bands in the Collie–Quambone, Coonamble–Gulargambone–Baradine, Nyngan–Tottenham and Tullamore–Parkes areas. The APLC aerially controlled a total of 5,135 ha of bands in an area east and south of Coonamble in mid-October. Fledging will follow in November in the Parkes–Peak Hill area.
The outlook is for more swarms to form in the Coonamble–Gulargambone–Baradine, Quambone–Warren, Nyngan–Tottenham and Tullamore–Peak Hill areas during November. Migration of young adults from Central West New South Wales to other regions is likely during November and these could form swarms in some areas. Swarm density egg laying is likely in early November in areas which received heavy rainfall at the end of October. There is the potential for a second generation of nymphs in Central West NSW during December and of an expansion of the infestation area to other regions including the Northwest Plains and Central North of New South Wales and southern Queensland.
Surveys in western New South Wales indicated that dry conditions have resulted in some mortality of nymphs in the Ivanhoe–Menindee area and reduced the risk of a large infestation. However, there were small mid-instar bands in the Ivanhoe–Mossgiel area in mid-October. Band density nymphs were reported from one location in the Narrandera area of the Riverina in mid-October.
There was no significant population change in Queensland during October and no reports of activity of this species. Conditions remained dry in most regions and were unsuitable for locust breeding. Heavy rainfall at the end of October in the South Central and Darling Downs regions and storm rains in the Southwest will provide soil and vegetation conditions for a population increase. Significant immigration from New South Wales is possible during November.
No locust activity was reported from South Australia during October and vegetation was very dry in the Far Northeast region. Rainfall in the Northeast and parts of the Northwest regions in the first half of October will provide suitable conditions for locust breeding and a small increase in population is possible.
Low numbers of adults and mid-instar nymphs were reported from the area around Echuca in North Central Victoria in mid-October.
In Western Australia nymphs were reported from many properties in the Central Agricultural region, including the Southern Cross, Merredin and Lake Grace areas during October. Nymphs were also reported from the Salmon Gums and Jerramungup areas in the Western Agricultural region.
Forecast development dates for indicative locations in NSW, Queensland and South Australia
| Location - NSW | Egg laying | Hatching | Mid-instar | Fledging |
|---|---|---|---|---|
| Coonamble-Collie | 6 November | 27 November | 7 December | 22 December |
| Coonamble-Quambone | 5 June | 15 September | 27 September | 20 October |
| Peak Hill-Parkes | 24 March | 30 September | 15 October | 5 November |
| Nyngan-Tullamore | 11 November | 2 December | 12 December | 27 December |
| Walgett-Goodooga | 10 November | 30 November | 10 December | 24 December |
| Narrabri - Wee-Waa | 11 November | 3 December | 13 December | 27 December |
|
Location - Qld |
Egg laying | Hatching | Mid-instar | Fledging |
| Cunnamulla-St George | 11 November | 27 November | 7 December | 21 December |
| Quilpie | 5 November | 22 November | 1 December | 15 December |
|
Location - SA |
Egg laying | Hatching | Mid-instar | Fledging |
| Coober Pedy | 12 October | 31 October | 11 November | 26 November |
| Hawker-Orroroo | 12 October | 9 November | 20 November | 6 December |
Forecast dates in the table above are based on development models for egg laying by known or possible adult populations and assuming sufficient soil moisture for direct development. Development dates are estimated from longtern average temperatures. Dates indicate the start of the majority of the population entering the life stage. Forecast dates will be updated regularly. Expect variation around these dates as any actual egg laying will vary from nominated dates and hatchings could extend for several weeks.
Spur-throated Locust (Austracris guttulosa)
There were several reports of swarms in the Mt Isa area in Northwest Queensland during October. There were also swarms reported in the Winton, Dajarra, Richmond and Julia Creek areas during winter, and several reports of tree damage. The number of locusts caught in the Julia Creek light trap fell during October after high numbers during August and September. Surveys in September and October identified a widespread Scattered–Numerous density adult population in Central West Queensland, and mainly Isolated density adults in the Central Highlands and South Central Queensland, and the Northwest Plains of New South Wales.
The development of over-wintering swarms is common in Queensland after immature adults redistribute in late autumn. These swarms feed on tall grasses and trees during winter. There are also likely to be a number of swarms in the Queensland Gulf and parts of the Barkly Tableland at this time of year. Adults will migrate and disperse to commence breeding from the start of the northern wet season.
Migratory Locust (Locusta migratoria)
There were no surveys in areas where this species is common during October. There were Isolated density adults in parts of the Central Highlands NSW Northwest LHPA during early spring. Pasture conditions were generally dry in the Central Highlands and South Central Queensland, but with the seasonal rainfall expectation for these areas some localised breeding and population increase is possible during the forecast period
2 November 2009