How many mice does an owl eat in a year? - briefly
A common owl typically ingests about 300–600 mice over the course of a year, with variation due to species size and local prey density. Larger raptors, such as great‑horned owls, can approach 1,000 small‑mammal captures annually.
How many mice does an owl eat in a year? - in detail
The amount of rodent prey an owl captures over twelve months varies with species, body size, habitat quality and seasonal prey abundance.
A typical barn owl (Tyto alba) in temperate regions consumes roughly 2–3 mice each night when small mammals are plentiful. Multiplying by 365 days yields an annual intake of about 730–1,095 individuals. In areas with lower prey density, nightly captures may drop to 1–1.5 mice, resulting in 365–548 per year.
A great horned owl (Bubo virginianus) is larger and can handle bigger prey, but it still includes mice in its diet. Average nightly intake of 1–2 mice (often supplemented with larger vertebrates) translates to 365–730 mice annually.
Factors influencing the yearly total include:
- Species – smaller owls rely more heavily on mice; larger species diversify diet.
- Age and reproductive status – breeding pairs increase hunting frequency to feed chicks.
- Habitat productivity – grasslands and agricultural fields support higher rodent populations.
- Seasonality – winter scarcity reduces nightly captures; spring and autumn peaks raise numbers.
- Human impact – pesticide use and habitat loss can depress local mouse abundance, lowering owl consumption.
For a rough baseline, most medium‑sized owls in environments with stable rodent populations ingest between 500 and 1,200 mice per year. Adjustments upward or downward depend on the specific conditions listed above.