Rodent management and cereal production in Asia: Balancing food security and conservation

Abstract

Rodents present a major problem for food security in Asia where smallholder farming families are particularly vulnerable. We review here recent developments in the biology and management of rodent pests in cereal cropping systems in Asia. The past decade has seen a strong focus on ecologically‐based rodent management (EBRM), its adoption in field studies significantly increased rice yields (6–15%) and income (>15%) in seven Asian countries. EBRM principles have also been successfully applied to maize in China. We provide case studies on EBRM in Cambodia, on interactions between rodent pests and weeds, and on the importance of modified wetlands for biodiversity and rodent pest management. Knowledge on post‐harvest impacts of rodents is increasing. One research gap is the assessment of human health impacts from a reduction of rodent densities in and around houses. We identify 10 challenges for the next decade. For example, the need for population modelling, a valuable tool missing from our toolbox to manage rodent pests in cereal systems. We also need to understand better the interactive effects of cropping intensification, conservation agriculture and climate change. Finally, new management approaches such as fertility control are on the horizon and need to be considered in the context of smallholder cereal farming systems and mitigating health risks from zoonotic diseases associated with rodents. © 2021 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Optimizing the capture of neophobic rice field rats in lowland Asian rice ecosystems

“…13 In Vietnam, detailed modelling of rodent impacts in lowland rice systems using the APSIM-Oryza rice model concluded that the CTBS approach was effective for the Vu3 crop in the Mekong Delta. 59 The CTBS has also been effective in China (see Singleton, et al 60 for review).…”

Rodents in agriculture and public health in Malawi: Farmers’ knowledge, attitudes, and practices

“…It is important to invest in research and innovation in order to introduce EBRM, which helps simultaneously reduce yield losses by rodents and the risks of rodent-associated infections in an environmentally friendly manner (Singleton et al, 1999;Makundi and Massawe, 2011;Singleton et al, 2021). EBRM is an approach that relies on a deep understanding of the diversity, behavior, ecology, and population dynamics of rodents as well as the perceptions and practices of humans (Singleton, 2014;Singleton et al, 2021). It mobilizes an array of rodent management methods that are integrated into robust community-based actions adapted to local situations.…”

“…Additionally, it minimizes the development of resistance by rodents to rodenticides. The effectiveness of EBRM has been documented in Southeast Asian agroecosystems, especially in rice fields, where local farmers seem to largely favor using EBRM in a community-based approach (Singleton, 2014;Singleton et al, 2021). However, despite its promising potential, progress in implementing EBRM in Africa has been very slow, apart from recent small-scale trials in smallholder settings (see Makundi and Massawe, 2011;Swanepoel et al, 2017;Constant et al, 2020).…”

“…There has been little focus on the impact of rodents on crop yields during production in Malawi, and the public health risks associated with them have not been fully considered. Furthermore, since effective management of rodents is a communal and not an individual matter (Singleton et al, 2021), it is important to document the knowledge, attitudes, and practices (KAP) of these farmers regarding rodents in Malawi. It is also important to document the rodent species that occur in Malawi's agroecosystems.…”

The status of fertility control for rodents—recent achievements and future directions

“…This could require planting more crops per year and will lead to an increase in the duration of breeding of pest rodent species (see review, Singleton et al . 2021). The basis for the occurrence of such outbreaks is the high reproductive potential of small rodents that allows them to produce many large litters in a short time (Andreassen et al .…”