Australian Plague Locust Commission Research Articles

Daily mapping of Australian Plague Locust abundance

Locust population outbreaks have been a longstanding problem for Australian agriculture. Since its inception in the mid-1970s, The Australian Plague Locust Commission (APLC) is responsible for monitoring, forecasting and controlling populations of several locust pest species across inland eastern Australia (ca. two million km2). Ground surveys are typically targeted according to prevailing environmental conditions. However, due to the sheer size of the region and limited resources, such surveys remain sparse. Here we develop daily time-step statistical models of populations of Chortoicetes terminifera (Australian plague locust) that can used to predict abundances when observations are lacking, plus uncertainties. We firstly identified key environmental covariates of locust abundance, then examined their relationship with C. terminifera populations by interpreting the responses of Generalized Additive Models (GAM). We also illustrate how estimates of C. terminifera abundance plus uncertainties can be visualized across the region. Our results support earlier studies, specifically, populations peak in grasslands with high productivity, and decline rapidly under very hot and dry conditions. We also identified new relationships, specifically, a strong positive effect of vapour pressure and sunlight, and a negative effect of soil sand content on C. terminifera abundance. Our modelling tool may assist future APLC management and surveillance effort.

Modeling spatiotemporal dynamics of outbreaking species: influence of environment and migration in a locust.

Many pest species exhibit huge fluctuations in population abundance. Understanding their large-scale and long-term dynamics is necessary to develop effective control and management strategies. Occupancy models represent a promising approach to unravel interactions between environmental factors and spatiotemporal dynamics of outbreaking populations. Here, we investigated population dynamics of the Australian plague locust, Chortoicetes terminifera, using density data collected between 1988 and 2010 by the Australian Plague Locust Commission over more than 3 million km2 in eastern Australia. We applied multistate and autologistic multi-season occupancy models to test competing hypotheses about environmental and demographic processes affecting the large-scale dynamics of the Australian plague locust. We found that rainfall and land cover predictors best explained the spatial variability in outbreak probability across eastern Australia. Outbreaks are more likely to occur in temperate than tropical regions, with a faster and more continuous response to rainfall in desert than in agricultural areas. Our results also support the hypothesis that migration tends to propagate outbreaks only locally (over distances lower than 400 km) rather than across climatic regions. Our study suggests that locust outbreak forecasting and management systems could be improved by implementing key environmental factors and migration in hierarchical spatial models. Finally, our modeling framework can be seen as a step towards bridging the gap between mechanistic and more phenomenological models in the spatial analysis of fluctuating populations.

Satellite normalized difference vegetation index data used in managing Australian plague locusts

The Australian Plague Locust Commission (APLC) has a mandated role in monitoring, forecasting, and managing populations of key locust species across four Australian states. Satellite normalized difference vegetation index (NDVI) imagery is used to monitor vegetation condition in locust habitat and is integrated with mapping software to support forecasting and operations within the strategic framework of APLC activities. The usefulness of NDVI data for monitoring locust habitats is tested using historical control and survey records for the Australian plague locust, Chortoicetes terminifera (Walker). In arid habitat areas, control of high-density nymphal populations was consistently associated with high and increased relative NDVI during summer and autumn, providing important information for locating possible infestations. Regression models of NDVI data and regional biogeographic factors were fitted to summer survey records of C. terminifera presence and abundance. Models identified increased vegetation greenness, measured by a one-month positive change in NDVI, as having a significant positive relationship with nymph distributions, while NDVI was significant in adult distributions. Seasonal rainfall regions and a binary habitat stratification were significant explanatory factors in all models.

Beyond all Utterance: Reflections on the making of the films Memoirs of a Plague and Locusts: Creatures of the flood

All visible objects, man, are but as pasteboard masks.- Herman Melville, Moby Dick1This paper reflects on the making of two very different films by the author. Both films were on the same subject: our relationship with locusts. One film, Memoirs of a Plague, was a personal inquiry, informed by an ethnographic filmmaking approach. The other film, Locusts: Creatures of the flood, was created from the same source material as Memoirs of a Plague, but was made for an international cable television channel, according to the demand for a magazinestyle documentary.2BackgroundIn 2008 I started making an independent film called Memoirs of a Plague. The numerous journeys I undertook to make the film over the next three years took the form of a personal and idiosyncratic inquiry into locust control around the world. My initial thesis was that our reactions to the natural phenomenon of locusts may arise from long-held prejudices and myths, rather than the reality of the threat that they pose. The film was based on found situations where individuals and governments were confronting what they perceived to be a locust menace. The bulk of the funding for Memoirs of a Plague came from Screen Australia's Innovation Program.In the course of my filming of Memoirs of a Plague, National Geographic became interested in the project and commissioned the making of a television version. This was to be a bespoke film, which came to be called Locusts: Creatures of the flood. It was to be made from the same source material as Memoirs of a Plague.1While the cinematography in both films was inspired by National Geographic's leadership in natural history filmmaking, the film that I was to make for them would have to conform to a style to which their audiences had become accustomed. A commissioning editor explicitly told me that the form of Memoirs of a Plague was completely unsuitable for the audience to which they marketed their films; however, there was no manual to explain this difference or the process by which Memoirs of a Plague needed to be reconfigured for television.The stark difference in logic instantiated in Memoirs of a Plague and Locusts: Creatures of the Flood, and the approaches to filmmaking they stand for, is revealed when we reflect upon the way the two films were constructed. In what follows, I will compare and discuss some aspects of the making of the two films. I hope this discussion may contribute to critical understandings of how different the process of filmmaking can be when confronting the same subject. My own filmmaking practice has been strongly influenced by ethnographic films, modelled on the approach of filmmakers such as Jean Rouch, David MacDougall and Lucien Castaing-Taylor. In this spirit, I approached the filming of Memoirs of a Plague as an open-ended inquiry. I attempted to incorporate a sense of the process of filming as well as acknowledging my own relationship to the subject.In the case of Creatures of the Flood, the approach was to be very different. I was aware that this film was to be created as content for a market dominated by television-style documentary films, and where it is expected such films will provide an audience with both questions and answers.Filmic BeginningsMoby Dick inhabited my mind in 2007. I was nearing the end of three years of work on my film End of the Rainbow.* Reading about whales and the ocean was one way of escaping the intensity of finishing the film. I was fascinated by Ahab's obsessive pursuit of Moby Dick. The white whale speaks for many hounded creatures. This association led me to develop an idea I already had for a film on locusts - a subject that had interested me since my employment as a field officer with the Australian Plague Locust Commission when I first left university. I chose to ignore Herman Melville's advice. He cautioned against casting a character such as a locust: 'To produce a mighty book, you must choose a mighty theme. …

Predicting avian distributions to evaluate spatiotemporal overlap with locust control operations in eastern Australia

Locusts and grasshoppers cause considerable economic damage to agriculture worldwide. The Australian Plague Locust Commission uses multiple pesticides to control locusts in eastern Australia. Avian exposure to agricultural pesticides is of conservation concern, especially in the case of rare and threatened species. The aim of this study was to evaluate the probability of pesticide exposure of native avian species during operational locust control based on knowledge of species occurrence in areas and times of application. Using presence-absence data provided by the Birds Australia Atlas for 1998 to 2002, we developed a series of generalized linear models to predict avian occurrences on a monthly basis in 0.5 degrees grid cells for 280 species over 2 million km2 in eastern Australia. We constructed species-specific models relating occupancy patterns to survey date and location, rainfall, and derived habitat preference. Model complexity depended on the number of observations available. Model output was the probability of occurrence for each species at times and locations of past locust control operations within the 5-year study period. Given the high spatiotemporal variability of locust control events, the variability in predicted bird species presence was high, with 108 of the total 280 species being included at least once in the top 20 predicted species for individual space-time events. The models were evaluated using field surveys collected between 2000 and 2005, at sites with and without locust outbreaks. Model strength varied among species. Some species were under- or over-predicted as times and locations of interest typically did not correspond to those in the prediction data set and certain species were likely attracted to locusts as a food source. Field surveys demonstrated the utility of the spatially explicit species lists derived from the models but also identified the presence of a number of previously unanticipated species. These results also emphasize the need for special consideration of rare and threatened species that are poorly predicted by presence-absence models. This modeling exercise was a useful a priori approach in species risk assessments to identify species present at times and locations of locust control applications, and to discover gaps in our knowledge and need for further focused data collection.

Estimating and reducing the amount of Plains-wanderer (Pedionomus torquatus Gould) habitat sprayed with pesticides for locust control in the New South Wales Riverina

The potential effects of pesticides used to control locusts in the New South Wales Riverina on the endangered Plains-wanderer (Pedionomus torquatus) have been of concern since the early 1980s. We used geographical information systems (GIS) to determine the intersection of primary and secondary Plains-wanderer habitat areas with historical locust-control data and provide estimates of the area of Plains-wanderer habitat sprayed by the Australian Plague Locust Commission for control of locusts between 1977 and 2005. Peaks among these estimates, expressed as a percentage of the identified habitat occurring on nine 1:100000 map sheets within the New South Wales Riverina study area, corresponded with years of peak locust control activity, although the proportion of habitat affected was less than expected. The maximum amount of habitat exposed to pesticides occurred in 1993–94, when ∼16% of primary and 12% of secondary Plains-wanderer habitat was sprayed. Locust-control protocols during 2004–05 were altered to reduce the amount of Plains-wanderer habitat sprayed with fenitrothion from 16% to 1.5%, and to increase the use of the biological control agent, Metarhizium anisopliae var. acridum (Green Guard®), over plains-wanderer habitat from 0% to 3.6%. The use of Green Guard® during future locust control within Plains-wanderer habitat in the Riverina has been recommended in the draft NSW Plains-wanderer recovery plan (New South Wales National Parks and Wildlife Service 2002).

A case study of the Australian plague locust commission and environmental due diligence: Why mere legislative compliance is no longer sufficient for environmentally responsible locust control in Australia

The Australian Plague Locust Commission (APLC) manages locust populations across 2 million square kilometers of eastern Australia using the aerial application of chemical and biological control agents to protect agricultural production. This occurs via a preventative control strategy involving ultralow-volume spray equipment to distribute small droplets of control agent over a target area. The economic costs of, and potential gains stemming from, locust control are well documented. The application of insecticides, however, to fragile arid and semiarid ecosystems is a task that brings with it both real and perceived environmental issues. The APLC is proactive in addressing these issues through a combination of targeted environmental operational research, an ISO-14001-aligned Environmental Management System (EMS), and links with environmental regulatory and research institutions. Increasing due diligence components within Australian environmental legislation dictate that mere legislative compliance is no longer sufficient for industries to ensure that they meet their environmental obligations. The development of external research links and the formulation of an EMS for locust control have enabled the APLC to identify environmental issues and trends, quantify objective environmental targets and strategies, and facilitate continuous improvement in its environmental performance, while maintaining stakeholder support. This article outlines the environmental issues faced by the APLC, the research programs in place to address these issues, and the procedures in place to incorporate research findings into the organization's operational structure.

Advances in the control of locusts (Orthoptera: Acrididae) in eastern Australia: from crop protection to preventive control

Abstract Locusts can form dense bands and swarms that can cause substantial damage to pastures and crops. For many years, State Departments of Agriculture aimed to protect crops by conducting locust control programs in their agricultural areas but in recent years the Australian Plague Locust Commission (APLC) has conducted preventive control programs that begin in locust source areas in the interior. The current preventive control programs are the culmination of more than 70 years of continuous research, conducted for many years by CSIRO and State Departments of Agriculture and more recently, by the APLC. Early research followed the sequence of outbreaks in agricultural areas but by the 1960s, there was increasing evidence that locusts commonly bred in the interior and then migrated to agricultural zones. These migrations covered long distances, often from one state to another and in 1974 the APLC was established with the specific mandate to control locusts that posed an interstate threat. The rationale was for the APLC to control locusts both at source in the interior as well as in the agricultural zone. Controlling locusts in the interior had never been attempted before and an intense research program was initiated as part of APLC operations that has culminated in the current preventive locust control programs. Preventive control involves early intervention, where treatment begins with localised populations present early in breeding sequences and continues every generation thereafter. To rapidly locate and control localised locust infestations over a large part of eastern Australia, a Decision Support System for locust management was developed that integrates data from a wide variety of sources to help operations staff determine when and where to concentrate survey and control efforts. When threatening locust populations are detected, control teams can be rapidly deployed to wherever treatment is required. An integral part of locust control programs is limiting environmental and monetary costs so that an important component of APLC research has been to focus on reducing chemical use by using the lowest effective dose and by using products that can be applied in barriers 300–500 m apart so that only a small proportion of the area is sprayed. Increasing constraints on insecticide use, including the production of organic beef in locust source areas, has led to the development of a biological alternative. The latter program led to nearly 25 000 ha of locusts being treated with the biological agent Metarhizium during the 2000–01 locust season, the first large‐scale operational use of this biopesticide anywhere in the world.

THE OPERATION OF A GIS‐BASED DECISION SUPPORT SYSTEM FOR AUSTRALIAN LOCUST MANAGEMENT

Abstract The Australian Plague Locust Commission (APLC) is responsible for the monitoring and control of locust populations that pose a threat to agriculture in the inland areas of four Australian States, a total area of 2 million km2. A GIS‐based decision support system (DSS) is used to co‐ordinate the collection, processing, analysis and display of a range of spatial data for the forecasting of locust population development and to assist control operations. The resultant forecasts are used to help locate population aggregations early in a breeding sequence so as to enable effective preventive control. The data collection components of the DSS include wireless direct transfer of locust survey data from the field and daily internet collections of weather data. Locust distribution and age information is collected by APLC officers on regular vehicle surveys using GPS‐connected palmtop computers, and sent directly to a GIS server via high frequency (HF) radio modems. Locust reports from landholders and state extension staff are also incorporated into the system. The current survey data are used to estimate broad distributions, and to seed spatially‐explicit development models that can identify the timing of life stages that can be effectively managed. Information on the distribution of rainfall, temperature and wind‐fields is collected automatically from the internet and integrated with habitat information and locust distributions. Online weather data products from the Bureau of Meterology are also accessed regularly to assist in operational decision making.

FORECASTING AND MANAGEMENT OF MIGRATORY PESTS IN AUSTRALIA

Abstract The Decision Support System (DSS) used by the Australian Plague Locust Commission for management of several important migratory insect pests in Australia is described. The DSS is based on a Geographic Information System that integrates data on weather and habitat condition with the migration, development and distribution of the pest to prepare forecasts and aid decisions for control. The GIS is module based with the number and nature of the modules easily modified depending on the detail of data required to manage the pest concerned.

Recent developments in the use of fungi as biopesticides against locusts and grasshoppers in Australia

Abstract Since October 2000, the commercial product Green Guard®, based on the entomopathogenic fungus Metarhizium anisopliae var. acridum produced by SGB Pty. Ltd. Wodonga, Victoria, has been used by the Australian Plague Locust Commission for operational control of the Australian plague locust, Chortoicetes terminifera. The production, formulation, storage, efficacy and non-target effects are reviewed. Between October 2000 and January 2001 over 23,000 ha were treated at doses of 12 - 25 g/ha in 500 ml of oil. Under most temperate or hot conditions, control of over 90% of Australian plague locusts was obtained by day 14 post spraying, but under less favorable conditions control could take up to 21 d. The factors which make Green Guard® attractive for locust control in Australia include low cost, the absence of environmental effects, especially on aquatic organisms, and its suitability for use in organic beef production areas and where the use of chemical pesticides is undesirable. Large-scale field trial...

Review of the effects of organophosphorus and carbamate insecticides on vertebrates. Are there implications for locust management in Australia?

The Australian Plague Locust Commission uses the organophosphorus insecticide fenitrothion to control locust population increases across 2000000 km2 of eastern Australia. Although the impact of fenitrothion on non-target invertebrates has been studied, effects on vertebrates are largely unquantified. Lethal and sublethal impacts on vertebrates are a consequence of the use of organophosphorus and carbamate insecticides. Information detailing the effects of exposure on free-living animals, particularly for herpetofauna, is lacking. This paper reviews literature concerned with the impacts of organophosphorus and carbamate insecticides on terrestrial vertebrates and highlights the need for continued research into the effects of these chemicals, especially in Australia.

Comparison of measured fenitrothion deposits from ULV aerial locust control applications with those predicted by the FSCBG aerial spray model

The deposit of fenitrothion on vegetation arising from aerial control of the Australian plague locust, Chortoicetes terminifera (Walker), was compared with deposition predicted by the FSCBG aerial spray model. The correlation between predicted and actual data suggests that the FSCBG spray model can be used to indicate the impact of varying application parameters, for example, track spacing and flying height, on locust control as practised by the Australian Plague Locust Commission. Any operational changes suggested by the model can then be validated in field trials.

Droplet size spectra produced by the atomization of a ULV formulation of fenitrothion with a Micronair AU5000 rotary atomizer

The atomization of fenitrothion ULV by a Micronair AU5000 rotary cage atomizer was evaluated in a wind tunnel with an air velocity of 180 km h −1. The study involved characterization of the droplet size spectra produced by nine blade settings from 35 to 80 degrees with flow rates of 3.5, 4.0, 4.5 and 5.0 l min −1. As the flow rate rose the volume median diameter (VMD) increased but to a lesser degree as the rotational speed decreased. A 50 degree blade angle with flow rates of 3.5 and 5 l min −1, which is used by the Australian Plague Locust Commission for locust control, gave rotational speeds of 5510 and 5410 rev min −1, and droplet spectra with VMD values of 78 and 92 μm, respectively.

Likely locust infestation areas in western New South Wales, Australia, located by satellite

Abstract A retrospective investigation was undertaken of the area around Broken Hill in the Western region of New South Wales, where Australian plague locust (Chortoicetes terminifera) nymphal band control took place during September ‐ November (spring) of 1987. Processed Landsat‐5 multispectralscanner data for March 1987 (autumn) were used to locate the likely spring/summer locust infestation areas using habitat type, condition and soil type as the delineating parameters. The results show that a vegetation index (indicating the degree of vegetation greeness in an area) is useful for predicting where locusts are most likely to aggregate, a classification of vegetation types is needed for determining likely breeding sites, and that there is an additional relationship between soils/geology and the location of locust infestations. These results are discussed in relation to the future operational use of the techniques in the Australian Plague Locust Commission.

Acquisition and use of low-cost meteorological satellite data in the Australian Plague Locust Commission

Recent studies have shown that satellite data can be used in the detection and monitoring of potential outbreak areas of the Australian plague locust. However, the routine monitoring of such areas using Landsat MSS data is precluded by the high cost of the data, although it is still used selectively for forecasting. An alternative approach has been to make use of lower-cost meteorological satellite data with lower spatial resolution, for example that of the NOAA and GMS satellites, which provide an acceptable compromise between frequency of monitoring, relevant data and cost. This paper describes the acquisition of GMS LRFAX and NOAA APT data and other relevant meteorological data at the Australian Plague Locust Commission (APLC) Headquarters in Canberra and the use of the data in the APLC.

Digitally processed satellite data as a tool in detecting potential Australian plague locust outbreak areas

This paper presents an investigation into the use of digital satellite data as a tool in identifying potential Australian plague locust ( Chortoicetes terminifera (Walker)) outbreak areas at an early stage in semi-arid areas of south west Queensland. The results show that standard processing techniques of the digital data allow areas of green vegetation to be discriminated from soil background information (a problem encountered in an earlier investigation using commercially produced false colour imagery of the same data), thus enabling the detection of potential outbreak areas. The results are discussed in relation to future applications of satellite data in the Australian Plague Locust Commission.

The use of Landsat MSS data to determine the locust eggbeds of locust eggbeds in the Riverina region of New South Wales, Australia

Processed Landsat multispectral data were used to determine areas in the Riverina region of New South Wales, Australia, in which eggs were likely to have been laid by swarms of the Australian plague locust ( Chortoicetes terminifera (Walker)), which invaded the region at the end of March 1987. A map was produced from the processed data with potential eggbed areas highlighted, which could be used for field survey purposes in the spring and summer when hatching started. The results showed that > 95 per cent of all nymphal band targets were in the areas defined by a normalized difference vegetation index as being those where vegetation growth had resulted from rain during March. Furthermore, a maximum-likelihood classification using a known eggbed location as a training area, produced an excellent correlation with locusts hatching in September/October 1987. The results are discussed in relation to the future operational use of such techniques by the Australian Plague Locust Commission.