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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]

This paper examines how a move from traditional post-harvest operations of smallholder rice farms in the Ayeyarwaddy delta, Myanmar, to improved post-harvest operations affected income, energy efficiency and greenhouse gas emissions (GHGE). Harvest and post-harvest losses were investigated in a field experiment with 5 replications per scenario. A comparative analysis on energy efficiency and cost-benefits was conducted for different practices of rice production from cultivation to milling. GHGE of different practices were also considered using a life-cycle assessment approach. The study demonstrates that the mechanized practices increased the net income by 30–50% compared with traditional practices. Despite using additional energy for machine manufacturing and fuel consumption, the mechanized practices significantly reduced postharvest losses and did not increase the total life-cycle enegy and GHGE. Combine harvesting helped to significantly reduce harvesting loss in a range of 3 to 7% (by weight of the rice product). Improved post-harvest management practices with a flatbed dryer and hermetic storage reduced the discoloration of rice grains by 3 to 4% and increased head-rice recovery by 20 to 30% (by weight of rice product). The research findings provide empirical evidence that improved post-harvest management of rice in the Ayeyarwaddy delta, compared to traditional post-harvest operations by smallholder farmers, reduce post-harvest losses and improve the quality of rice. The findings provide valuable information for policy makers involved in formulating evidence-based mechanization policies in South and Southeast Asia. [ABSTRACT FROM AUTHOR]

Rice farmers in Southeast Asia are hesitant to adopt the water-saving technology, alternate wetting and drying (AWD), for fear the practice will lead to increased rodent pest activity, consequently exacerbating yield loss. We examined the effects of AWD on the population dynamics, habitat use and damage levels inflicted on rice crops by the most important rodent pest of rice in Indonesia and the Philippines, Rattus argentiventer and R. tanezumi, respectively. Rice crop damage levels were not affected by the water management scheme employed. Rodent activity in rice fields was not influenced by water level. Both species tended to use the rice paddies over bunds regardless of water level, indicating that something other than water affects their habitat use, and we argue it is likely that the perceived risk of predation is the primary factor driving habitat use. Activity levels and damage inflicted by rodent pests on rice were not correlated. AWD had no effect on breeding and population dynamics of these species. Breeding of R. argentiventer is tied to the growth stages of rice, while available resource dictates breeding by R. tanezumi. Our findings clearly indicate that rice farmers in both Indonesia and the Philippines have no cause to reject AWD based on concerns that AWD would exacerbate crop losses by rodents. Given AWD is being promoted as a climate-smart technology for rice production in Asia and Africa, we strongly recommend its adoption without concerns that it would aggravate rodent pest impacts in lowland irrigated rice cropping systems. [ABSTRACT FROM AUTHOR]

Food quantity and especially food quality are thought to be key factors driving reproductive changes in the house mouse, Mus domesticus, leading to outbreaks of house mouse populations in the Australian grain-growing region. Characteristic changes during an incipient mouse plague are an early start of breeding, a high proportion of females breeding at a young age and a prolonged breeding season. We conducted a large-scale food manipulation during an incipient mouse plague, which started with early breeding and relatively high spring numbers of mice. We measured background food availability in four farms throughout the study and conducted a food manipulation experiment from November to March in two of them. After harvest in December 100–200 kg/ha spilled grain remained in the stubble. This was depleted by March. In two treatment farms we added high-protein food pellets on a weekly basis between November and March and two farms served as controls. We measured changes in mouse numbers by capture-mark-recapture trappings and changes in reproduction by scoring embryos and recent placental scars at necropsy. Mouse numbers did not differ between treatments and controls. There were no differences in the litter size or the proportion of females breeding between treatments and controls. We observed the normal pattern of high litter size in spring and decreasing litter size towards the end of summer in treatments and controls. In all farms reproduction stopped in March. Mouse numbers were high but not at plague densities. Contrary to our prediction we did not observe food constraint affecting the reproduction of female mice. Our field experiment seems to rule out food quality as the driving factor for improved reproduction and formation of an outbreak of mice. We suggest that physiological mechanisms in mice might not enable them to take advantage of food with a high protein content in arid summers in southeastern Australian grain fields because of the lack of free-standing water. [ABSTRACT FROM AUTHOR]

The social behavior and reproductive success of individual house mice were monitored in an enclosure. The subjects were obtained from natural populations and were selected on the basis of the genotype at five genetic loci. Male mice formed a three-tiered social hierarchy. In two replicate experiments α-dominant males formed two well defined territories which they constantly patrolled and strongly defended for periods of 120-200 days. The subdominant and subordinate males resided along the periphery of the enclosure and were most active when the dominant males were resting. In the second experiment the subdominant males were able to establish territories after a period of 140 days. Reproductive females generally confined their movements to within the territorial boundaries of a single α-dominant male. Once a female occupied a nest box within a particular male's territory, she rarely entered the territory of the other a-dominant male. Genetic analysis of five segregating loci enabled ascertainment of the paternity of 13 of the litters born and indicated a strong association between social dominance and reproductive success. There was only one instance of gene flow between social breeding units. The genetic analysis therefore indicates that social organization has the potential to restrict gene flow within local populations of house mice. [ABSTRACT FROM AUTHOR]

Authors would like to correct error in affiliation in the original publication of the article. [ABSTRACT FROM AUTHOR]