How many offspring does a field mouse have at one time?

How many offspring does a field mouse have at one time? - briefly

A field mouse usually gives birth to 4–8 young per litter, averaging around 5–6 offspring. Litter size can fluctuate depending on species, season, and environmental conditions.

How many offspring does a field mouse have at one time? - in detail

Field mice (e.g., Apodemus sylvaticus, Microtus spp.) reproduce with a relatively short gestation of 19–23 days. A single breeding event typically yields a litter of 3–12 young, with most populations averaging 5–7 individuals per litter.

  • Species differences: wood mice usually produce 4–8 pups; meadow voles often reach the upper end of the range.
  • Seasonal influence: litters in spring and early summer tend to be larger than those in autumn.
  • Maternal condition: well‑fed, mature females generate more offspring than juveniles or nutritionally stressed individuals.
  • Habitat quality: abundant cover and food resources correlate with higher litter sizes.

Females can breed every 4–5 weeks under favorable conditions, allowing 5–7 litters per year. Consequently, a healthy adult may contribute 25–45 offspring annually, although predation and disease reduce the number that survive to independence.

Survival rates drop sharply after birth; approximately 30–50 % of neonates reach weaning age (≈3 weeks). The combination of high reproductive output and elevated juvenile mortality sustains field‑mouse populations despite intense predation pressure.