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BACKGROUND Reduction of vegetation height is recommended as a management strategy for controlling rodent pests of rice in South-east Asia, but there are limited field data to assess its effectiveness. The breeding biology of the main pest species of rodent in the Philippines, Rattus tanezumi, suggests that habitat manipulation in irrigated rice-coconut cropping systems may be an effective strategy to limit the quality and availability of their nesting habitat. The authors imposed a replicated manipulation of vegetation cover in adjacent coconut groves during a single rice-cropping season, and added artificial nest sites to facilitate capture and culling of young. RESULTS Three trapping sessions in four rice fields (two treatments, two controls) adjacent to coconut groves led to the capture of 176 R. tanezumi, 12 Rattus exulans and seven Chrotomys mindorensis individuals. There was no significant difference in overall abundance between crop stages or between treatments, and there was no treatment effect on damage to tillers or rice yield. Only two R. tanezumi were caught at the artificial nest sites. CONCLUSION Habitat manipulation to reduce the quality of R. tanezumi nesting habitat adjacent to rice fields is not effective as a lone rodent management tool in rice-coconut cropping systems. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Context. Asynchronous or aseasonal planting of rice crops can extend the period when high-quality food is available to rodents. Consequently, rodents may extend their breeding season, increasing population densities. An improved understanding of the effects of food availability and quality on rodent reproduction may enable better forecasts of high rodent population densities in response to asynchronous or aseasonal planting of crops. Aim. The present study examined the association between the quality and quantity of food and the reproductive success of female rice-field rats, Rattus tanezumi and Rattus argentiventer, in a lowland rice landscape in the Philippines. Methods. We evaluated the main dietary components of female rats on two different islands through a cropping season during the 2010 wet season. The breeding performance of 60 female R. tanezumi and 60 R. argentiventer individuals was measured. Key results. Our findings indicated the following: (1) the main dietary items for females of both rodent species during the main breeding season (the booting stage to harvest) were rice panicles and rice seeds; (2) the high protein content of the rice crop at the tillering stage triggered the onset of the main breeding season, leading to the highest rates of conception during the booting and ripening stages; (3) the quantity of food available at the stubble stage provided sufficient nutrient to maintain pregnancy and lactation by females; and (4) asynchronous planting and poor harvest technology could extend the breeding season of rice-field rats. Conclusions. We contend that the extension of the growing season by 3-4 weeks provides high-quality food for rodents, which in turn provides sufficient conditions for higher population densities. The availability of spilled rice grain at the stubble stage is a source of good-quality food for pregnant and lactating females, allowing extension of the breeding season. Implications. Synchronous planting (within 2 weeks) with good post-harvest management of rice stubble are important to prevent high population densities of rice-field rats in lowland rice landscapes in the Philippines. [ABSTRACT FROM AUTHOR]

BACKGROUND: Massive rodent population outbreaks occurred in the Ayeyarwady Delta, Myanmar, in July 2009, 15 months after cyclone Nargis. Satellite imagery with high temporal frequency was used to identify the area and planting time of rice at a landscape scale of > 80 000 ha, and household surveys of farmers were conducted to validate the mapping and to quantify losses. RESULTS: Farmers did not have problems with rodents in 2007-2008; rodents were the principal problem in the 2009 summer and monsoon rice crops. The landscape scale modeling indicated that high rodent densities in 2009 were associated with extended or delayed cropping and harvesting time because of asynchronous planting, and with an increase in the amount of abandoned agricultural land after cyclone Nargis. CONCLUSION: Asynchronous planting following cyclone Nargis provided abundant high-quality food for an extended period, which in turn led to a lengthened breeding season of rodents. The outbreak of populations 15 months after cyclone Nargis is consistent with the time it would take rodent populations to build from a low base after a major flooding event. To prevent rodent outbreaks effectively, synchronous planting, use of rice varieties with a similar maturation date and good field sanitation are important actions for subsequent rice crops after a major weather event. © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Context. Overabundant rodents cause considerable crop damage and, in developing countries of South-east Asia, rodents can be an obstacle to attempts at alleviating poverty. Management is often based on the use of chemicals that can harm non-target species. Therefore, an effective and environmentally benign management approach such as ecologically based rodent management (EBRM) is desirable. Aims. We compared the effectiveness of EBRM to that of conventional management on populations of rice-field rats (Rattus argentiventer). Methods. The study was conducted as a large-scale replicated field trial in lowland irrigated rice fields in West Java, Indonesia. EBRM actions included habitat manipulations, removal of rats with trap barrier systems, coordinated rat-control campaigns and synchrony of cropping on the village level. We measured abundance, population structure, and breeding of rice-field rats as well as rice production and crop damage caused by rats. Key results.Although there was no overall effect of the EBRM treatment on rat abundance, we found decreasing rat abundance in rice-field habitats at the late cropping stage in treated villages and a decrease in body size of rats. In addition, we found fewer reproducing females when EBRM was applied than with the application of conventional methods, whereas male reproductive condition did not decrease. Overall, there was a reduction in mean crop damage when EBRM was applied (4.4 ± 0.4% in treatments v. 2.5 ± 0.4% in experimental controls), which translated into 6% higher rice production. Conclusions. The results demonstrated that EBRM is an appropriate approach to manage overabundant rodents in irrigated lowland rice-based agro-ecosystems and possibly in other agro-ecosystems. This will provide substantial benefits for smallholder farming communities in developing countries and most likely benefits for ecosystem health. Implications. The EBRM approach should be used routinely in irrigated lowland rice crops that are at risk of damage by rice-field rats. [ABSTRACT FROM AUTHOR]

Several rodent species damage rice crops and commensal rodents cause damage to stored produce and infrastructure, hygienic problems and they can transmit zoonotic pathogens. In the first such study in Sri Lanka, we identified the main rodent and shrew species and the extent of post-harvest damage caused in rice storage facilities of smallholder farmers. Netting of rice bags was trialled as a new measure of protection. Field experiments were performed in the three main agro-ecological zones of Sri Lanka. Five rodent species and one shrew species were captured in storage facilities. Rattus rattus , Bandicota indica and Suncus murinus were the dominant species in storage facilities. The small mammal composition was more related to season than to region. In storage, depending on region, 3.2–9.1% (mean 7.6%) of rice was lost to rodents when rice was stored indoors in unprotected polyethylene bags. Netting around bags reduced damage by 89% - equivalent to the annual rice consumption of one person per storage facility, reduced the presence of rodent droppings by 92% and the bag area damaged by rodents by 96%. Our findings clearly show the considerable amount of damage caused by rodents to rice post-harvest across three agro-ecological zones of Sri Lanka and indicate that netting bags considerably reduces damage and contamination. This netting can be used to aid the development of an ecologically-based rodent management (EBRM) program tailored to local conditions. More detailed studies are needed to fully understand the population and breeding ecology of the relevant rodent pest species in relation to damage patterns to optimize management beyond individual structural measures. [Display omitted] • Rattus rattus and Suncus murinus were dominant in Sri Lankan rice storage facilities. • The small mammal composition was more related to season than to region. • 7.6% of rice was lost to rodents when rice was stored indoors in polyethylene bags. • Netting around bags reduced damage by 89% and damaged bag area by 96%. • Netting around bags reduced the presence of rodent droppings by 92%. [ABSTRACT FROM AUTHOR]

Identifying the adverse impacts of pesticide exposure is essential to guide regulations that are protective of wildlife and human health. Within rice ecosystems, amphibians are valuable indicators because pesticide applications coincide with sensitive reproductive and developmental life stages. We conducted two experiments using wild cane toads (Rhinella marina) to test 1) whether environmentally relevant exposure to a commercial formulation of butachlor, an acetanilide herbicide used extensively in rice, affects amphibian development and 2) whether cane toad tadpoles are capable of acclimatizing to sub-lethal exposure. First, we exposed wild cane toads to 0.002, 0.02, or 0.2 mg/L of butachlor (Machete EC), during distinct development stages (as eggs and hatchlings, as tadpoles, or continuously) for 12 days. Next, we exposed a subset of animals from the first experiment to a second, lethal concentration and examined survivorship. We found that cane toads exposed to butachlor developed slower and weighed less than controls, and that development of the thyroid gland was affected: exposed individuals had smaller thyroid glands and thyrocyte cells, and more individual follicles. Analyses of the transcriptome revealed that butachlor exposure resulted in downregulation of transcripts related to metabolic processes, anatomic structure development, immune system function, and response to stress. Last, we observed evidence of acclimatization, where animals exposed to butachlor early in life performed better than naïve animals during a second exposure. Our findings indicate that the commercial formulation of butachlor, Machete EC, causes thyroid endocrine disruption in vertebrates, and suggest that exposure in lowland irrigated rice fields presents a concern for wildlife and human health. Furthermore, we establish that developmental assays with cane toads can be used to screen for adverse effects of pesticides in rice fields. Image 1 • Realistic exposure to butachlor affected development of cane toad tadpoles. • Animals developed slower, weighed less, and the thyroid gland was affected. • Non-monotonic response; low concentration, 0.002 mg/L, produced the largest effects. • Exposure caused extensive downregulation of transcripts. • Cane toad tadpoles can acclimatize to some herbicide exposures. Environmentally relevant exposures to a commercial formulation of butachlor, an herbicide used extensively in rice, affect development, morphology, and gene expression of cane toad tadpoles. Developmental assays with cane toad tadpoles can be used to screen for adverse effects of pesticides in rice fields. [ABSTRACT FROM AUTHOR]

Evidence-based information for smallholder farmers on where and when to conduct rodent management is vital given that most are resource poor and depend on agriculture for food and income. However, there is scarce information on how the foraging activity of rodent pests changes over agricultural cropping seasons. We used the concepts of giving-up-density (GUD) and landscape of fear to monitor how the foraging activity of rodent pests changes in and around maize (Zea mays) fields over the cropping season. We tested the hypothesis that the foraging activity of rodent pests will be influenced by vegetation cover, perceived predation risk and food availability. Mastomys natalensis was the dominant species in all maize fields (n = 3, 87.05 % of the total captures). We observed that the foraging activity of rodents was influenced by vegetation cover and food availability. During the germination stage, rodent activity in the natural habitat and along the border was higher than inside the maize fields. During land preparation, planting, weeding, maize tasselling, maturity, and post-harvest stages, there was no difference in the foraging activity in and around the maize fields. During the harvest stage, the foraging activity was higher in the maize fields than along the border and in the natural habitat. These results can be used to guide smallholder farmers where and when to focus rodent control measures during different stages of the cropping season. An additional approach would be to develop strategies that could potentially increase rodent fear perceptions in cropping landscapes. • Giving-up-density and landscape of fear used in monitoring the foraging activity of rodent pests. • Mastomys natalensis was the dominant species in all maize (Zea mays) fields. • Rodent foraging activity was influenced by vegetation cover and food availability. • These results of foraging activity of rodent pests can be used to guide where and when to focus rodent control measures. [ABSTRACT FROM AUTHOR]

1. Pest mammals have severe economic, environmental and social impacts throughout the world. Fertility control could reduce these impacts. Virally vectored immunocontraception (VVIC) has been proposed as an economic way to achieve this. However, the ability of an immunocontraceptive virus to control populations may be compromised if: (i) sufficient infected mice are not made infertile; (ii) the virus does not transmit at a sufficient rate; (iii) there is competition with field strains of virus; or (iv) its ability to induce infertility is altered by the presence of field strains. We tested this with stochastic, individual-based, disease–host models based on murine cytomegalovirus (MCMV) and house mice Mus musculus domesticus. 2. Using field estimates of the MCMV transmission rate, immunocontraceptive MCMV (icMCMV) could prevent mouse populations from growing rapidly to damaging levels provided > 70% of mice infected with the virus became infertile. Successful control was possible even if engineering icMCMV reduced its transmission rate to c. 30% of the field-estimated value, but greater reductions in the transmission rate compromised successful control. 3. Effective control was compromised if there was competition between icMCMV and field strains because of cross-immunity to infection or if previous infection with field strains blocked the development of infertility in mice subsequently infected with icMCMV. In these cases effectiveness was diminished, particularly if the transmission rate of icMCMV was reduced relative to field strains, or if close to 100% infertility of infected mice could not be achieved. If the blocking developed early after infection with field strains, doubling the transmission rate of icMCMV relative to field strains still could not produce successful control. 4. Synthesis and applications. VVIC requires preliminary estimates of its efficacy to satisfy regulatory requirements before it can be released into the environment. Our models indicate that successful control of an outbreaking species using VVIC is possible if high levels of infertility can be achieved, but this is compromised by cross-strain protection and low transmission rates of engineered virus. Future research effort should focus on determining whether these compromising effects occur for specific engineered viruses and, if so, whether they can be overcome. [ABSTRACT FROM AUTHOR]

The advent of 'conservation agriculture' (CA) farming using zero- or no-tillage practices and an accompanying change in crop rotations in the last 10–15 years has potentially led to less disturbance of mouse burrows and increased cover and food supply. Given the irregular outbreaks of mice in grain cropping regions in Australia and the damage they cause, it is important to understand when and where mouse populations increase so that management strategies can be improved. We utilised a 20-year long-term mouse population data set collected prior to the introduction of CA farming practices and a more recent 8-year data set after CA to compare changes in mouse population abundance in a typical dryland grain cropping system in north-western Victoria, Australia. Mouse trapping data were used to compare abundance in crop and margin habitats during crop growth and non-crop (fallow) periods before ('conventional') and after introduction of CA. Mice are now resident year-round within crops and stubble and appear to only spill over into margin habitats. Previously developed recommendations for mouse management that include their control while in margin habitats may no longer be valid. [ABSTRACT FROM AUTHOR]

Most small rodent populations in the world have fascinating population dynamics. In the northern hemisphere, voles and lemmings tend to show population cycles with regular fluctuations in numbers. In the southern hemisphere, small rodents tend to have large amplitude outbreaks with less regular intervals. In the light of vast research and debate over almost a century, we here discuss the driving forces of these different rodent population dynamics. We highlight ten questions directly related to the various characteristics of relevant populations and ecosystems that still need to be answered. This overview is not intended as a complete list of questions but rather focuses on the most important issues that are essential for understanding the generality of small rodent population dynamics. [ABSTRACT FROM AUTHOR]

• Yield gap of 24–42%, profit gap of 36–82% and gaps in other indicators exists in six Asian countries. • In Vietnam, >80% of pesticide application practices are unsustainable. • Decrease fertilizer rates in Guangdong and Yogyakarta and increase in Bago, and increases labor productivity in Yogyakarta. • A greenhouse gas reduction potential of 25–35% exists across the six Asian countries. • SRP indicators could make rice production systems profitable with reduced environmental footprint. Quantifying and comparing sustainability indicators are essential to improve the sustainability of smallholder rice cropping systems. The sustainability of rice production systems can be measured based on economic, environmental, social, and institutional indicators. In this paper, we restrict our assessment to economic and environmental indicators. During 2012–2015, farmers were interviewed from 847 households from intensively irrigated rice production regions in Vietnam, Thailand, Indonesia, Myanmar, Sri Lanka, and China. We assessed the sustainability of their farming practices using economic and environmental indicators, i.e., eight of the 12 performance indicators (PIs), as defined by the Sustainable Rice Platform (SRP). Across the six sites, there was a yield gap of 24–42% and a profit gap of 36–82% between the 10% highest-performing farms (mean of top decile) and the mean-performing farms. In addition, there was a labor productivity gap of 12–32%, a nitrogen use efficiency (NUE) gap of 11–20%, a phosphorus use efficiency (PUE) gap of 1–29%, and a water productivity gap of 12–42%. Deliberate modification of conventional practices, including not flooding the field for >30 days before rice planting, incorporating pre-rice crop residue >30 days before planting, and adoption of mid-season drainage or alternate wetting and drying irrigation rather than continuous flood irrigation during the rice growing period, could substantially reduce the greenhouse gas (GHG) emission in irrigated rice fields without yield penalty. There is an urgent need to adopt improved management strategies for nitrogen (N), phosphorus (P), potassium (K) fertilizer, irrigation water-use efficiency, as well as for decreasing pesticide use frequency, without sacrificing profitability and yield. We identified the following priority interventions for each site: a) increasing fertilizer use and adopting higher-yielding varieties in Bago, Myanmar; b) reducing pesticide application rates in Can Tho, Vietnam; c) reducing fertilizer use in Guangdong, China; d) reducing nitrogen and labor use in Yogyakarta, Indonesia; e) reducing fertilizer and water use in Polonnaruwa, Sri Lanka and; f) reducing fertilizer use in Nakhon Sawan, Thailand. Additional uses of the PI analysis clearly demonstrated that rice yield and profit gaps can sustainably be closed by increasing efficiencies that will also lead to reduced environmental footprint. [ABSTRACT FROM AUTHOR]

• We examined the diet of two rice field amphibians across two separate rainy seasons. • We identified prey items and tested for differences in diet composition. • The native Luzon wart frog consumed more rice pests (54.1%) than the cane toad. • The invasive cane toad consumed a disproportionate amount (89.4%) of predators. • The Luzon wart frog may provide pest control in rice agro-ecosystems. Lowland irrigated rice fields serve the dual purpose of providing an essential food crop to the world's most populous regions and functioning as man-made wetlands that harbor a diversity of organisms. Amphibians occupy rice fields throughout Asia and South America, but little is known about their functional role in the rice ecosystem. We conducted field surveys in Los Baños, Philippines over two separate rainy seasons (2015 and 2017) to determine whether native Luzon wart frogs and invasive cane toads consume rice pests, and if so, which species was more effective in doing so. We also examined diet composition to test whether the two species compete for food resources in rice fields. We found that despite smaller body sizes, the Luzon wart frog consumed the same total mass of prey as the cane toad (although it consumed fewer total prey items), and that pests made up the largest proportion (54.1%) of its total diet. In contrast, the majority (89.4%) of the cane toad's diet consisted of beneficial arthropod predators. Taxonomic analyses of diet composition and breadth revealed that the diet of Luzon wart frog was distinct from that of the cane toad, although there was overlap, and that both species consumed diverse array of prey. Taken together, these data suggest adult Luzon wart frogs may provide effective pest control services, and that they may not be in direct competition over food resources with adult cane toads in rice fields. We also present the first evidence suggesting that cane toads may indirectly damage rice crops by consuming beneficial predators integral to the function of lowland rice ecosystems. We suggest that rice agro-ecosystems should be managed to promote species such as the native Luzon wart frog, and to reduce populations of the introduced cane toad in order to safeguard native biodiversity while simultaneously improving yields and reducing insecticide input. [ABSTRACT FROM AUTHOR]

The desire to increase agricultural productivity through the high usage of agrochemicals is causing substantial environmental deterioration. Many developing countries lack the capacity to quantify agro-pollution, especially in the case of chemical inputs such as pesticides, preventing them from formulating action plans to mitigate the negative environmental impacts of agro-chemicals. This study aims to address the knowledge gap in Sri Lanka by assessing water quality at a temporal and geospatial scale, focusing on areas with significant agricultural inputs in the Deduru Oya river basin of Sri Lanka. To assess water quality, 183 samples were collected biweekly in the 2019 dry season (Yala) and 2019/2020 wet season (Maha) and analyzed for 39 parameters, including pesticides, heavy metals, minerals and physico-chemical properties. Of the twenty pesticides tested, ten were detected in the water samples (pretilachlor, oxyfluorfen, thiamethoxam, chlorantraniliprole, fenobucarb, fipronil, diazinon, etofenprox, tebuconazole, and captan) and concentrations of all detected pesticides exceeded national regulatory threshold limits. Heavy metal residues were not detected in the water. Pesticide and mineral levels varied widely and exhibited lack of evenness across seasons and locations. Pesticide contamination was higher in the wet season than the dry season. Temporal variation was more pronounced than spatial variation for many of contaminants. No clear trend in contaminant accumulation was observed as sampling progressed downstream from the main reservoir. In both seasons, natural or inorganic fertilizer mineralization and pesticide inputs into the agricultural systems were identified as the main factors underlying water pollution in the study area. [Display omitted] • Ten pesticides detected in water at various non-source points of Deduru Oya basin. • Significant temporal variability in water quality. • Underlying factors for water quality in each season were discovered. • Basin scale studies are important to assess water quality. [ABSTRACT FROM AUTHOR]

Sustainability of rice production systems is a prime concern for Asia to maintain food security and to support economic growth. This gain in productivity not only depends on agricultural inputs but also depends on social and environmental factors. To address these emerging issues, new resource- and capital-efficient and profitable technologies have been introduced. The conventional method of rice production (puddling and manual transplanting, PTR) is considered as highly input intensive. As an alternative, dry direct seeded rice (DSR) using seed drill has been promoted to save labor and production costs compared with PTR. Similarly, machine transplanted rice (MTR) has been also considered and promoted in many rice growing countries of South and East Asia. Economic, environmental, and social performances of DSR and MTR (alternative rice establishment technologies) were compared to the PTR using Sustainable Rice Platform (SRP) defined 12 Performance Indicators (PIs) (version 1.0) as a gauge to measure their sustainability. For that, a household survey was conducted on 652 households in Odisha India during 2016. The gaps, i.e., the target to achieve better sustainability, were computed for most of the indicators from the difference between top 10th percentile and the population mean value of the indicator. The results indicated a yield gap of 1.35 t ha−1, a profit gap of $273 ha−1, labor productivity gap of 21 kg day−1, nitrogen (N) use efficiency gap of 22 kg grain kg−1 N, phosphorus (P) use efficiency gap of 105 kg grain kg−1 P, and water productivity gap of 0.00010 kg grain L−1 water in rice production systems in Odisha. Among the compared technologies, MTR results in the highest yield, profit, labor productivity, nitrogen-, phosphorus-use efficiency, and water productivity (at par), and is positive for children's welfare and the overall energy productivity, indicating better sustainability and has the potential to replace PTR. Direct seeded rice has the highest yield gap (1.57 t ha−1; 38%) but has the lowest production cost (can reduce the cost of production by $130 ha−1), and the highest greenhouse gas (GHG) reduction potential. SRP PIs are capable for assessing the sustainability of rice establishment technologies except for a few indicators, for example food safety and workers health and safety, which are more applicable to watershed and household level indicators, respectively. The SRP PIs provide scientific evidence and practical impetus for the selection and promotion of sustainable rice production technologies. Image 1 • Significant yield, profit, labor productivity, nutrient-use-efficiency gaps exist with current practice of rice production. • Machine transplanted rice had relatively minimal trade-off than manual transplanting & dry direct seeded rice. • Optimization of fertilizer, water, pesticide, labor, and production costs are necessary for improving sustainability. • Direct seeded rice has the highest greenhouse gas reduction potential than conventional and machine transplanted. • A significant scope exists to further improve the sustainability indicators to well define sustainability of rice production. [ABSTRACT FROM AUTHOR]

Background: The mechanisms that regulate multi-annual population dynamics of rodent pest species of cereal crops is often unknown. Better knowledge of such aspects can aid pest management and in turn improve food security and human health. The patterns and processes of the population dynamics of Rattus argentiventer, in rice fields of Indonesia, and Rattus tanezumi, in rice fields of the Philippines were assessed in this article., Results: The meta-analysis of trapping data over 20 years in Indonesia, and 16 years in the Philippines indicated that rodent populations in rice fields did not show a regular multi-annual pattern. Rattus argentiventer populations in Indonesia responded to less rainfall from the current year. Rattus tanezumi populations in the Philippines responded positively to both rainfall and rainfall anomaly with a 1-year time lag., Conclusions: Our study of long-term population data indicates that certain combinations of rainfall parameters could be useful to predict years when there is higher rodent abundance in rice fields. The key rodent pest species in rice fields in Indonesia (R. argentiventer) and the Philippines (R. tanezumi) differ, and the populations of each species respond differently to rainfall anomalies. Other factors such as crop cover and water availability may also be important and should be considered in future work. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry., (© 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.)

Current reactive pest management methods have serious drawbacks such as the heavy reliance on chemicals, emerging genetic rodenticide resistance and high secondary exposure risks. Rodent control needs to be based on pest species ecology and ethology to facilitate the development of ecologically based rodent management (EBRM). An important aspect of EBRM is a strong understanding of rodent pest species ecology, behaviour and spatiotemporal factors. Gaining insight into the behaviour of pest species is a key aspect of EBRM. The landscape of fear (LOF) is a mapping of the spatial variation in the foraging cost arising from the risk of predation, and reflects the levels of fear a prey species perceives at different locations within its home range. In practice, the LOF maps habitat use as a result of perceived fear, which shows where bait or traps are most likely to be encountered and used by rodents. Several studies have linked perceived predation risk of foraging animals with quitting-harvest rates or giving-up densities (GUDs). GUDs have been used to reflect foraging behaviour strategies of predator avoidance, but to our knowledge very few papers have directly used GUDs in relation to pest management strategies. An opportunity for rodent control strategies lies in the integration of the LOF of rodents in EBRM methodologies. Rodent management could be more efficient and effective by concentrating on those areas where rodents perceive the least levels of predation risk. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry., (© 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.)

1. Outbreaks of feral house mice, Mus domesticus, in Australia represent a fundamental failure of the behavioural control mechanisms of population density, as proposed in the hypothesis of self-regulation. 2. Mice have the potential to keep numbers in check via a suite of spacing behaviours; however, the self-regulation hypothesis implies that some social change occurs that permits the population to erupt. It also suggests that at different phases of an outbreak, distinct patterns of social activity are evident. 3. We compare predictions from two models encapsulating the self-regulation hypothesis as applied to feral house mice in south-eastern Australia. Each model may be distinguished by the timing of aggressiveness between mice that leads to a closed social system. We compare individual turnover, residency and territoriality in each sex and age cohort during the increase, peak and low phases of a population outbreak that peaked in 2001. 4. The activity of 438 mice was monitored via intensive mark-recapture trapping and an automated event recording system that detected the activity of 300 marked individuals at burrow entrances. 5. Our findings support the second model, which suggests that mice switch from an almost asocial structure at low densities to a territorial system as abundance increases. Adult females appear more likely than males or juveniles to make the significant social shift. The trigger for this change remains unclear and several alternative mechanisms are proposed.