How many mice are there on Earth? - briefly
Approximately one to two billion mice inhabit the planet, based on global wildlife surveys and population modeling. This figure includes both wild and commensal species across diverse ecosystems.
How many mice are there on Earth? - in detail
The global mouse population is estimated in the low billions. Recent analyses, combining data from agricultural surveys, urban pest‑control reports, and ecological studies, suggest a range of roughly 1 – 2 billion house mice (Mus musculus) and an additional 3 – 7 billion wild mouse individuals (including species such as the field mouse, wood mouse, and various peridomestic species). The aggregate figure therefore lies between 4 and 9 billion individuals.
Key factors influencing the estimate:
- Habitat coverage – cultivated land, urban environments, and natural ecosystems collectively provide millions of square kilometres of suitable habitat.
- Reproductive capacity – a single female can produce up to 10 litters per year, each containing 5‑8 offspring, enabling rapid population growth under favourable conditions.
- Mortality rates – predation, disease, and human control measures reduce local densities but do not prevent overall abundance.
Methodological approaches used to derive these numbers include:
- Capture‑Mark‑Recapture (CMR) – repeated trapping in defined plots yields local density estimates, which are extrapolated to larger regions.
- Agricultural loss assessments – reports of grain damage quantify pest pressure, allowing back‑calculation of mouse numbers in farming areas.
- Urban pest‑control records – service companies provide data on trap counts and bait usage, offering insight into city‑wide populations.
- Ecological modeling – habitat suitability models combine climate, land‑use, and vegetation data to predict potential mouse distribution and density.
Uncertainties remain due to uneven data quality across continents, seasonal fluctuations, and the cryptic nature of many wild species. Nevertheless, the convergence of multiple independent sources supports a worldwide mouse population on the order of several billion individuals.