Polyandry enhances offspring survival in an infanticidal species

The adaptive significance of polyandry is an intensely debated subject in sexual selection. For species with male infanticidal behaviour, it has been hypothesized that polyandry evolved as female counterstrategy to offspring loss: by mating with multiple males, females may conceal paternity and so prevent males from killing putative offspring. Here we present, to our knowledge, the first empirical test of this hypothesis in a combined laboratory and field study, and show that multiple mating seems to reduce the risk of infanticide in female bank voles Myodes glareolus. Our findings thus indicate that females of species with non-resource based mating systems, in which males provide nothing but sperm, but commit infanticide, can gain non-genetic fitness benefits from polyandry

Interspecific information on predation risk affects nest site choice in a passerine bird

Abstract Background: Breeding site choice constitutes an important part of the species niche. Nest predation affects breeding site choice, and has been suggested to drive niche segregation and local coexistence of species. Interspecific social information use may, in turn, result in copying or rejection of heterospecific niche characteristics and thus affect realized niche overlap between species. We tested experimentally whether a migratory bird, the pied flycatcher Ficedula hypoleuca, collects information about nest predation risk from indirect cues of predators visiting nests of heterospecific birds. Furthermore, we investigated whether the migratory birds can associate such information with a specific nest site characteristic and generalize the information to their own nest site choice. Results: Our results demonstrate that flycatchers can use the fate of heterospecific nesting attempts in their own nest site choice, but do so selectively. Young flycatcher females, when making the decision quickly, associated the fate of an artificial nest with nest-site characteristics and avoided the characteristic associated with higher nest predation risk. Conclusions: Copying nest site choices of successful heterospecifics, and avoiding choices which led to failed attempts, may amplify or counter effects of nest predation on niche overlap, with important consequences for between-species niche divergence-convergence dynamics, species coexistence and predator-prey interactions

Multiple predators induce risk reduction in coexisting vole species

Large predators may affect the hunting efficiency of smaller ones directly by decreasing their numbers, or indirectly by altering their behaviour. Either way this may have positive effects on the density of shared prey. Using large outdoor enclosures, we experimentally studied whether the presence of the Tengmalm's owl Aegolius funereus affects the hunting efficiency of the smallest member of the vole-eating predator guild, the least weasel Mustela nivalis, as measured by population responses of coexisting prey species, the field vole Microtus agrestis and the sibling vole M. levis. We compared the density and survival probability of vole populations exposed to no predation, weasel predation or combined predation by a weasel and an owl. The combined predation of both owl and weasel did not result in obvious changes in the density of sibling and field vole populations compared to the control populations without predators, while predation by least weasel alone decreased the densities of sibling voles and induced a similar trend in field vole densities. Survival of field voles was not affected by predator treatment while sibling vole survival was lower in predator treated populations than in control populations. Our results suggest that weasels are intimidated by avian predators, but without changing the effects of predators on competitive situations between the two vole species. Non-lethal effects of intraguild predation therefore will not necessarily change competitive interactions between shared prey species

Socio-Economic tools for rodent management research: recent experience from Africa and Asia

The scientific development of anti-coagulant rodenticides led to a complete transformation of rodent pest control services throughout the world. Suddenly it became economically practical to eradicate localised rodent populations in agricultural or urban environments. The success of chronic poisons became doctrine among rodent experts. However, understanding how rodent behaviour was exploited by chronic poisons, the differences between chronic and acute poisons, and the way poisons need to be delivered, continue to be poorly understood by the general public and people attempting to manage their own rodent pest problems. The success of chronic rodenticides has its limitations prescribed by human knowledge, socio-cultural context and, of course, by the nature of the rodent pest problem experienced. In short, our best rodent management tools can and do fail when individuals and experts do not understand the circumstances and tools with which they are attempting to carry out rodent management. Recently completed research to develop ecologically-based rodent management (EBRM) strategies for rural agricultural communities in Bangladesh and South Africa has shown that it is vitally important to understand the knowledge, attitudes and practices (KAP) of people experiencing rodent pest problems. Tools for evaluating ethno-ecology and human behaviour were developed and implemented as part of these EBRM research projects. Community focus groups were used to understand the decision making process and the risks and benefits of rodents and management actions. Resource maps, cropping calendars and decision analysis matrices helped describe the opportunities and constraints experienced by community members; while changes in human behaviour in response to rodent management interventions were monitored through the use of individual KAP survey questionnaires and farmer diaries. By using these socio-economic tools, it was possible to quantify the impact of rodent pests on people’s livelihoods as well as the cost-benefits of new rodent management strategies. Data from these studies showed that communities could cost-beneficially reduce rodent impacts. Participatory approaches of research were adopted which allowed rodent ecology research to be carried out that would not have otherwise been feasible, while at the same time improving knowledge among community members about rodents and appropriate management strategies. The prospects of positive long-term changes in human behaviour were enhanced through using these socio-economic tools. Anthropological and economic studies are essential when trying to understand the impact of rodents on people’s lives. Research in the RatZooMan project studying the role of rodents in the transmission of zoonotic diseases in southern Africa showed that human behaviour and actions are often responsible for the persistence and spread of zoonosis in the environment as well as affecting the individual risk of exposure to disease. Socio- economics also affect people’s health care seeking behaviour, causing delay or inappropriate treatment choices. Witchcraft, curses, superstitions and religion can influence the fundamental knowledge within a community about human disease and can even affect the way in which rodent pest problems are perceived and managed. Scientists who desire to be praised (and not cursed) for their research on rodent pest management would ignore the socio-economic aspects of rodent management at their per

Socio-Economic tools for rodent management research: recent experience from Africa and Asia

The scientific development of anti-coagulant rodenticides led to a complete transformation of rodent pest control services throughout the world. Suddenly it became economically practical to eradicate localised rodent populations in agricultural or urban environments. The success of chronic poisons became doctrine among rodent experts. However, understanding how rodent behaviour was exploited by chronic poisons, the differences between chronic and acute poisons, and the way poisons need to be delivered, continue to be poorly understood by the general public and people attempting to manage their own rodent pest problems. The success of chronic rodenticides has its limitations prescribed by human knowledge, socio-cultural context and, of course, by the nature of the rodent pest problem experienced. In short, our best rodent management tools can and do fail when individuals and experts do not understand the circumstances and tools with which they are attempting to carry out rodent management. Recently completed research to develop ecologically-based rodent management (EBRM) strategies for rural agricultural communities in Bangladesh and South Africa has shown that it is vitally important to understand the knowledge, attitudes and practices (KAP) of people experiencing rodent pest problems. Tools for evaluating ethno-ecology and human behaviour were developed and implemented as part of these EBRM research projects. Community focus groups were used to understand the decision making process and the risks and benefits of rodents and management actions. Resource maps, cropping calendars and decision analysis matrices helped describe the opportunities and constraints experienced by community members; while changes in human behaviour in response to rodent management interventions were monitored through the use of individual KAP survey questionnaires and farmer diaries. By using these socio-economic tools, it was possible to quantify the impact of rodent pests on people’s livelihoods as well as the cost-benefits of new rodent management strategies. Data from these studies showed that communities could cost-beneficially reduce rodent impacts. Participatory approaches of research were adopted which allowed rodent ecology research to be carried out that would not have otherwise been feasible, while at the same time improving knowledge among community members about rodents and appropriate management strategies. The prospects of positive long-term changes in human behaviour were enhanced through using these socio-economic tools. Anthropological and economic studies are essential when trying to understand the impact of rodents on people’s lives. Research in the RatZooMan project studying the role of rodents in the transmission of zoonotic diseases in southern Africa showed that human behaviour and actions are often responsible for the persistence and spread of zoonosis in the environment as well as affecting the individual risk of exposure to disease. Socio- economics also affect people’s health care seeking behaviour, causing delay or inappropriate treatment choices. Witchcraft, curses, superstitions and religion can influence the fundamental knowledge within a community about human disease and can even affect the way in which rodent pest problems are perceived and managed. Scientists who desire to be praised (and not cursed) for their research on rodent pest management would ignore the socio-economic aspects of rodent management at their per