They are grazing animals and typically live in single-sex groups of up to 150 deer until mating season, when the males spread out among their territory. In areas with high human populations, they tend to become nocturnal.

They do much of their feeding in open grassy areas but like tree cover and undergrowth for shelter during the winter.

Mating season occurs between October and November, and one calf is usually born in June or July, after a 229-day gestation period. Although males do not live longer than 10 years, females can live up to 16 years.

Fallow deer are not threatened, and their populations are often controlled through hunting.

They are native to Eastern Europe, but have been introduced to the United States and the U.K.