Many deer species—including fallow deer—have a social organization which can be tremendously plastic depending on their environment, meaning that group size and habitat type are closely linked to herd size.
It is important to note that most of the detailed research on the ecological characteristics and behaviour of fallow deer occur in large blocks of woodland, which means there may be some bias present.
Fallow deer can be found in a variety of habitats, which can range from cool and wet to hot and dry.
Fallow deer seem to have a preference for older forests with dispersed areas of grass, trees, and a variety of other vegetation.
The largest herd occurs right before the rutting season, while the smallest groups are females with fawns.
Throughout a large portion of the year the sexes remain separated and only congregate during the mating months; however, other patterns may be described, such as bachelor groups and even mixed groups.

In male fallow deer, their low frequency groans are produced by vocal tracts that are of consistent but complex shape.
Experimentation showed that vocal production of these groans are dependent on both their nasal and oral cavities.

Ruts are characterized by males gaining the best territory possible to increase their odds for mating and are often characterized by the presence of females on stands.
During this time, males will stop feeding to defend their ruts from subordinate males.
Males defending this territory will often lose an average of 17% of their body weight, and the liver will exhibit steatosis, which is reversible.
Throughout breeding seasons, the male may obtain the same rut; in some cases, ruts can be held by more than one individual; some possibilities for this include high population density and less rut space, or more suitable habitats which can be shared.
Many deer species—including fallow deer—have a social organization which can be tremendously plastic depending on their environment, meaning that group size and habitat type are closely linked to herd size. It is important to note that most of the detailed research on the ecological characteristics and behaviour of fallow deer occur in large blocks of woodland, which means there may be some bias present. Fallow deer can be found in a variety of habitats, which can range from cool and wet to hot and dry. Fallow deer seem to have a preference for older forests with dispersed areas of grass, trees, and a variety of other vegetation. The largest herd occurs right before the rutting season, while the smallest groups are females with fawns. Throughout a large portion of the year the sexes remain separated and only congregate during the mating months; however, other patterns may be described, such as bachelor groups and even mixed groups.
In male fallow deer, their low frequency groans are produced by vocal tracts that are of consistent but complex shape. Experimentation showed that vocal production of these groans are dependent on both their nasal and oral cavities.
Ruts are characterized by males gaining the best territory possible to increase their odds for mating and are often characterized by the presence of females on stands. During this time, males will stop feeding to defend their ruts from subordinate males. Males defending this territory will often lose an average of 17% of their body weight, and the liver will exhibit steatosis, which is reversible. Throughout breeding seasons, the male may obtain the same rut; in some cases, ruts can be held by more than one individual; some possibilities for this include high population density and less rut space, or more suitable habitats which can be shared.
Fallow deer