Mice infestation& Population dynamics in a urban

environment

Daniel Neves, PCO.BSc (HONS)

Mice significance

• Hazardous to health• Damage to food stocks• Damage to building• Aesthetics and Nuisance

Mice Biology

• Secretive, small size, very mobile and nearly everywhere

• Primarily nocturnal• Sporadic eaters 3-4g. per day, can survive without

water• Fast Breeders, population can double every 3-4

weeks• Small territory 10-12 m. Arround nest

2001 English House Condition Survey

•EHCS based on 26,300 property with adequate data on approximately 17,500 of these.

•Mice activity reported in last 12 months or noticed by surveyor.

•Average infestation level 1.4%.

Percentage of rodent infestations treated at the time of survey.

Whether Pest Control carried out by a professional

Infestation levels in 2001 categorised by whether or not properties were infested in 1996.

Infestation rates by severity of problems in the area

•Surveyors rated factors such as litter, neglected buildings, scruffy gardens, vacant buildings and vandalism.• Results were combine and plotted against overall ratings, total sums up to 100%.

Infestation rates by age of property

Growth of a population of mice•growth rate is small when the population size is either small or large•Growth rate is highest when at an intermediate level relative to the carrying capacity•Limiting factors make the birth rate decrease, the death rate increase or both

How mice population behave

• Size of mice population is limited to the food supply and harbourage available in any given environment .

• If allowed, mice population will build up to the carrying capacity, then it will transit toward the surrounding areas.

Limitation of baiting and trapping

Benefit of proofing and tidying

Infestation remediation

• Educating customers and the community• Keep living space clean, dry and well

maintained• Reduce food, water, shelter and movement• Exclusion from rooms, buildings and other

structures• Apply judiciously pesticide when necessary

Main References

• Rodent infestations in domestic properties in England, 2001. Department of Environment, Food and Rural Affairs. Website: www.defra.gov.uk

• Commensal Rodent – Biology, Population Dynamics & IPM. Bio-Integral Resource Center. Website: www.birc.org

The end