Acorns play an important role in forest ecology when oaks are the dominant species or are plentiful. The volume of the acorn crop may vary widely, creating great abundance or great stress on the many animals dependent on acorns and the predators of those animals. Acorns, along with other nuts, are termed mast.
Wildlife that consume acorns as an important part of their diets include birds, such as jays, pigeons, some ducks, and several species of woodpeckers. Small mammals that feed on acorns include mice, squirrels and several other rodents. Acorns have a large influence on small rodents in their habitats, as large acorn yields help rodent populations to grow.
Ponies eating acorns. Acorns can cause painful death in equines, especially if eaten to excess amounts.
Large mammals such as pigs, bears, and deer also consume large amounts of acorns; they may constitute up to 25% of the diet of deer in the autumn. In Spain, Portugal and the New Forest region of southern England, pigs are still turned loose in dehesas (large oak groves) in the autumn, to fill and fatten themselves on acorns. Heavy consumption of acorns can, on the other hand, be toxic to other animals that cannot detoxify their tannins, such as horses and cattle.
The larvae of some moths and weevils also live in young acorns, consuming the kernels as they develop. Happy hunting!
