How many offspring does a field mouse have per litter? - briefly
A field mouse usually bears 4 to 7 offspring per litter, averaging roughly five pups. Litter size can vary with species, season and environmental conditions.
How many offspring does a field mouse have per litter? - in detail
Field mice typically produce between three and seven pups in a single birth, though litters as large as twelve have been recorded in optimal conditions. The average litter size for the common European meadow mouse (Apodemus sylvaticus) falls near five offspring.
Several variables influence this number:
- Seasonality – Breeding during late spring and summer yields larger litters because food availability peaks.
- Maternal age and condition – First‑time mothers often have smaller litters; experienced females with ample body reserves can increase offspring count.
- Habitat quality – Areas with abundant seeds and insects support higher reproductive output.
- Genetic factors – Certain populations exhibit genetically driven differences in litter size.
The gestation period lasts approximately 19–21 days. Females may become pregnant again within a few days after giving birth, allowing up to five or six litters per year in temperate zones. Consequently, a single female can produce 20–30 young annually under favorable circumstances.
Survival to weaning is variable; roughly 40‑60 % of pups reach the age of three weeks, after which mortality declines sharply. Predation, competition, and environmental stressors are the primary causes of early loss.
In summary, a field mouse generally gives birth to five young per reproductive event, with the range extending from three to twelve depending on environmental and physiological factors. Multiple breeding cycles per year amplify the species’ reproductive potential, enabling rapid population growth when conditions permit.