Results of a 15-year systematic survey of commensal rodents in English dwellings

Abstract

Population trends for commensal rodents are the subject of interest and speculation but accurate data are rarely available. Here we report data from a 15-year systematic survey of rats and mice in English dwellings and present national-level estimates of prevalence for 1996–2010. We found evidence for peaks in prevalence of mice inside and rats around dwellings in 2002 and 2008. Models containing twelve variables relating to the dwelling and local area explained some but not all of the variation in prevalence. Older dwellings, those in rural areas, those with litter, drainage faults and pets or other animals outdoors tended to have higher levels of rodent prevalence. Regional differences were found but there were no seasonal trends apart from lower prevalence of mice during summer. Rodent prevalence was generally higher in rented (compared to owner-occupied) dwellings, although apparently not due to reduced tendency to carry out rodent control. The percentage of households having taken some form of action against active rodent problems varied according to prevalence at the national level, and therefore appropriate data on number of rodent control treatments carried out each year could likely act as a useful index of household rodent prevalence.

Not in My Backyard: Public Perceptions of Wildlife and ‘Pest Control’ in and around UK Homes, and Local Authority ‘Pest Control’

“…A number of species are commonly regarded as problematic in and around UK homes and often acquire the label of 'pest' or 'vermin'. For example, brown rats (Rattus norvegicus) and house mice (Mus domesticus) pose human and animal health risks and damage property and food [4,5]. European mole (Talpa europaea) activity in gardens often results in what is considered 'damage' [6].…”

“…There is little information on the rate of wildlife conflict, or its causes, in and around UK homes, but useful data exist on rat and mouse problems. The prevalence of Norway rats and house mice in and around English domestic homes was estimated using a systematic survey between 1996 and 2010 [4,5]. Over the 15-year period, mice were found to be present in 1.7-2.65% of dwellings, while rats were present inside 0.28-0.46% of properties and outside 2.09-3.92% of dwellings [4].…”

Interplay between historical and current features of the cityscape in shaping the genetic structure of the house mouse (Mus musculus domesticus) in Dakar (Senegal, West Africa)

“…Deviations from the main genetic pattern resulting from historical processes can be attributed to the current heterogeneity of the cityscape in terms of habitat quality for the house mouse (Adrichem et al, 2013;Byers et al, 2019;Combs et al, 2018a,b;Lambert et al, 2017;Lucaccioni et al, 2016;Masi et al, 2010;Santos et al, 2017). Spatial variations in the level of genetic differentiation are often interpreted as reflecting the presence of physical barriers to individual dispersal, while they may actually result from variations in effective population size, i.e.…”

“…In these areas, the presence of numerous warehouses to stock different food products such as groundnuts, rice, sugar and flour (Ba et al, 2013) would allow to sustain large and continuous population of mice. The second situation could explain why high-standing residential areas, which are already known to be less prone to commensal rodent infestations (Adrichem et al, 2013;Byers et al, 2019;Combs et al, 2018a,b;Lambert et al, 2017;Masi et al, 2010), are characterized by low levels of genetic diversity (H s ) and high levels of differentiation.…”

“…Such genetic breaks have been attributed to physical barriers to dispersal (waterway in Baltimore, USA -Gardner-Santana et al, 2009; roads and topography in Pau de Lima, Salvador, Brazil -Kajdacsi et al, 2013;Richardson et al, 2017) or spatial heterogeneity in habitat quality that impacts local population size (resource availability varying with socioeconomic features of urban infrastructures, Manhattan, USA -Combs et al, 2018b). The need to integrate socioeconomic features of the urban environment in population dynamic and genetic studies of commensal rodents is advocated by previous works that have shown that areas with poor housing conditions (including building material quality, sanitation status within and outside the houses) and commercial premises are more prone to rodent infestations than high-standing residential or touristic areas (Adrichem et al, 2013;Byers et al, 2019;Combs et al, 2018a;Jassat et al, 2013;Lambert et al, 2017;Lucaccioni et al, 2016;Masi et al, 2010;Santos et al, 2017). In addition to current features, spatial genetic patterns may also reflect past demographic events related to cityscape evolution during the historical timeframe of urbanization Lourenço et al, 2017).…”