How much grain does a field mouse eat?

How much grain does a field mouse eat? - briefly

A field mouse usually eats 2–3 g of grain daily, which corresponds to roughly 5–10 % of its body weight. This intake can vary with food availability and season.

How much grain does a field mouse eat? - in detail

Field mice (e.g., Apodemus sylvaticus) weigh 15–25 g and maintain a high basal metabolic rate. To sustain body temperature and activity, they must ingest a substantial proportion of their body mass each day.

  • Laboratory measurements report daily grain intake of 2–4 g, equivalent to 8–15 % of body weight.
  • Field observations show average consumption of 1.5–3 g per 24 h, with peaks up to 5 g during breeding season.
  • Energy derived from these grains provides roughly 10–12 kJ (2.5–3 kcal) per gram, meeting the mouse’s daily energy demand of 30–45 kJ.

Several variables modify these figures:

  • Seasonal grain availability: abundant harvests raise intake by up to 30 %; scarcity reduces it to 1 g or less.
  • Reproductive status: lactating females increase consumption by 40–60 % to support offspring.
  • Habitat temperature: colder conditions elevate metabolic costs, prompting higher grain consumption.

The cumulative effect of individual consumption can impact stored grain supplies. In a typical barnyard, a population of 200 mice may remove 300–600 g of grain per day, potentially causing significant loss over a harvest period.

In summary, a single field mouse ingests roughly 2 g of cereal seeds each day, with fluctuations driven by environmental and physiological factors. This intake translates to a modest but measurable portion of stored grain, especially when populations reach high densities.