spring 2011 will be massively reduced compared to the situation in spring 2010. While there was egg-laying in various districts, the density and size of predicted hatching areas is not expected to cause landowners exceptional difficulties in most situations. No mass autumn migrations of locusts (from interstate) have occurred, but patches of localised activity can be expected in agricultural areas where locusts were present during autumn. Locust patches were reported from a wide range of agricultural areas this autumn ranging from Naracoorte in the South East to Ceduna in the Far West, but were generally small in size and/or low in density compared with 2010. Locust numbers in most cropping areas are expected to be within the normal capacity of landholders to manage through targeted ground spraying or spot spraying in spring. A small, highly
Following the major Australian plague locust outbreak that occurred in South Australia, Victoria and other Australian states in 2010 and early 2011, locust numbers have returned to near normal levels in most areas. Landholders mounted a tremendous response to the emergence of locust hoppers across large parts of these states in spring 2010, and continued their treatment efforts into the summer and autumn of 2011. This widespread treatment, coupled later in the season with natural factors, has resulted in a dramatic fall in locust numbers. Locust activity has declined in all agricultural areas with the onset of winter. Surveys in recent months have indicated that the risk from locusts in
targeted aerial program may be required to control bands in some locations in the North of South Australia (Hawker –Orroroo–Burra). Biosecurity SA will continue to monitor these situations closely. Years of major plagues are rare, and are mainly influenced by particular weather conditions similar to those experienced in 2010, particularly in the home breeding areas in north-west New South Wales and south-west Queensland. More detailed information is available on the Australian Plague Locust Commission website ( www.daff.gov.au/animal-plant- health/locusts/current ) including advice on how to monitor your property for locusts, how to treat locust hoppers and what impact they may have on particular agricultural businesses.
Forecast Australian plague locust development 2011 Location - NSW Egg laying Hatching Mid-instar Fledging Cootamundra-Junee 15 March 1 October 15 October 6 November Wagga-Lockhart 20 March 7 October 18 October 9 November Corowa-Oaklands* 10 March 9 October 22 October 12 November Location - Victoria Egg laying Hatching Mid-instar Fledging Yarrawonga-Echuca 20 March 15 October 28 October 16 November Bendigo-Boort 15 April 17 October 31 October 22 November Horsham-St Arnaud* 15 April 23 October 2 November 26 November Stawell-Ararat* 15 April 25 October 5 November 2 December Hamilton-Lake Bolac* 15 April 5 November 25 December 12 December Location - SA Egg laying Hatching Mid-instar Fledging Hawker-Orroroo* 15 April 4 September 22 September 15 October Port Augusta-Jamestown* 15 April 26 August 16 September 12 October Burra-Clare* 15 April 10 September 28 September 20 October Sedan-Mannum* 15 April 22 September 1 October 31 October Elliston-Kimba* 15 April 25 September 10 October 2 November Keith-Naracoorte* 15 April 16 October 1 November 20 December Location - QLD Egg laying Hatching Mid-instar Fledging Thargomindah-Quilpie 15 April 18 August 5 September 29 September
DPI staff collect locust hopper samples at Red Cliffs in 2010 Photo courtesy DPI VIC
Locust spraying in spring 2010 near Patchewollock Photo courtesy DPI VIC