General information about deer
Deer belong to the group ruminants. The males usually have branching antlers, which are shed and regrown each year. In Sweden, there are four wild species of deer: moose, red deer, fallow deer, and roe deer. The reindeer also belongs to the deer family, but wild reindeer in Sweden were exterminated as late as the end of the 1800s. However, wild reindeer can still be found in both Norway and Finland.
Most deer live in larger or smaller groups. Group size varies with the species and the time of year.
Deer are polygamous, meaning that one male will, if possible, mate with several females. For all deer species except roe deer, mating season or rut occurs in the fall, and the young are born in spring or early summer the following year. Roe deer rut already at the turn of July–August, and is the only one of our deer species that has delayed embryo development. The embryo develops extremely slowly in the womb during the fall, and development doesn’t accelerate until around the turn of the year. The gestation period for roe deer is therefore long, about 300 days, compared to the moose’s 240 days.
FLIGHT ANIMALS
The survival strategy of deer relies on detecting danger as early as possible and fleeing. They are fast and enduring and have very well-developed senses. The sense of smell and hearing are the sharpest. A moose, a human, or a predator can be detected from several hundred meters away under good conditions, and the deer reacts instantly to weak noises such as the rustling of clothes or the safety being switched off on a firearm. Hunters’ experience also considers their vision to be good, especially in red and fallow deer.
Although most deer flee from danger, they are not defenseless. Adult moose and deer often defend themselves successfully using hooves and antlers. Moose hunting with barking dogs is based on the moose’s natural behavior of defending itself against predators. Even red deer may occasionally stand their ground when approached by dogs.
RUTTING SEASON
During the rut, or mating season, the males compete for the attention of the females. In red deer, which rut in September, this occurs through dominant males, known as territorial stags, attracting as many females as possible to mate with each of them. These stags must use a lot of time and energy to keep their harems together and scare off rival males from mating with any of the hinds.
Many large stags are so worn out after the rut that they don’t survive the winter.
Roe deer rutting is not as dramatic as that of red deer, but even the roe buck loses weight and condition during this time. He defends his territory energetically and monitors intruding bucks while courting the local females. He often doesn’t let a selected doe out of his sight for several days and mates with her multiple times.
During the rut, moose bulls can walk long distances to find cows to mate with. A moose cow is only receptive to mating for about one day and the bull must be present then. The cow may actively seek out a suitable bull. Otherwise, she will enter heat again about three weeks later and repeat the process several times during the fall. Late-born calves with low body weights may be a sign of bull shortage. The rutting period is also very demanding for bull moose, and they use up all the extra fat reserves built up over the summer.
RUMINANTS
Plant food consists largely of cellulose, which is difficult for the digestive system to break down. Different animal groups have solved this problem in various ways. Deer do it through rumination.
Ruminants chew their food twice. They have four stomachs and a highly specialized digestive system. New food first ends up in the rumen, which is the largest of the stomachs, and then in the reticulum. After being partially broken down and mixed with saliva, it is regurgitated, chewed again, and then swallowed into the omasum. Water is absorbed there before the food is broken down further in the abomasum.
Despite this complex procedure, not all plant matter is fully digested, and ruminant droppings can therefore serve as nutrition primarily for many insects.
Ruminating explains some of the animals’ behavior. Anyone who has observed a moose, deer, roe deer, or perhaps even a cow for a while has likely noticed that the animal grazes for a bit and then lies down to ruminate the food just eaten. This is behavior worth noting—especially for stalking hunters. Too many stalking hunts have been ruined because the game was hidden in the vegetation and suddenly got up and fled.
THE HOOVES
Deer, like wild boar and mouflon, have hooves. A hoof is a toe tip reinforced on the outer edges with keratin, the same material our fingernails are made of. Hoofed animals have two forward-pointing hooves on each leg, which carry the animal’s full weight, and two small backward-pointing dewclaws. These are placed slightly higher and only leave tracks when the animal is running, jumping, or if the ground is soft.
THE ANTLERS
Deer antlers are made of bone. The antlers act as a kind of rank indicator among males. They are used to impress, and more rarely for fighting or defense. A male that for some reason loses his antlers ends up at the bottom of the hierarchy.
The size of the antlers is determined by genetics, nutrition, and the animal’s age. They grow from pedicles, bony outgrowths on the skull. During the entire growth phase, the antlers are covered in a blood-rich velvet. When the antlers are fully developed, the velvet dries up and is rubbed off against trees and bushes – a process called antler rubbing.
Freshly rubbed antlers are red from the velvet but later turn dark brown. The color depends largely on the types of plants the antlers have been rubbed against.
The antlers are shed when the layer between the pedicle and the antler base, called the burr, weakens and loosens. Velvet begins quickly to form over the broken pedicle, and new antlers start growing again.
Roe bucks start shedding their antlers already in October. Moose bulls and stags don’t lose their antlers until late winter. A general rule is that the animals that rut first—usually the older bulls—shed their antlers first, and the younger ones last.
A moose bull, roe buck, red deer or fallow buck is said to be in their prime when they carry their largest antlers. In general, antler volume and mass increase with age and then decline again, producing so-called regression antlers.
Antlers are not only the status symbol of males but also serve as the hunter’s trophy. Beautifully mounted, they often decorate the walls of homes or hunting cabins as memories of a successful hunt. Antlers are scored using a special system, and trophies that exceed certain point thresholds receive the Swedish Hunters’ Association’s horn medals. The purpose of scoring is not to reward the shooter but to acknowledge the landowner or hunting rights holder. The scores are seen as a measure of the land’s wildlife productivity and the quality of game management practiced.
TEETH AND AGE
When determining the age of deer, teeth provide good guidance. With increasing age, they wear down, and the chewing surfaces are smoothed out. To roughly estimate an animal’s age, however, its teeth must be compared to a so-called tooth scale or age scale, with a number of reference jaws from animals of known age from the same area.
A more accurate method is called tooth sectioning, where a tooth is cut, for example with a hacksaw blade or knife, and the annual growth rings in the cementum (the tissue that fastens the tooth to the jaw) are counted under magnification. The cementum continues to grow with a certain seasonal variation. A wide band is laid down during summer and a narrow one during winter, similar to tree rings.
With moose, it can sometimes be difficult to distinguish a large, well-developed calf from a yearling. However, a calf only has four molars in each side of the lower jaw. A yearling has six, even though the innermost may not be fully developed. A yearling can in turn be distinguished from an older, adult moose by the appearance of the first three molars. In yearlings, these are significantly lighter in color than the inner teeth, and the milk teeth may remain as “shells” on the emerging permanent teeth.
IMPORTANT FOR HUNTERS AND PREDATORS
In nature, deer are a very important prey species, primarily for large predators. Wolves and lynx rely heavily on deer or their carcasses. The fox is a significant predator of roe deer fawns, and the bear preys on moose calves.
Since ancient times, deer have also been an important food resource for humans, and even today, moose hunting has great local significance for household meat supply. Measured in kilograms of meat, the yield from Swedish moose and deer hunting is many times greater than that of all other hunting combined. Of other game species, only wild boar can compare to moose, deer, and roe deer in this regard.
Due to the large carnivores’ strong recovery in recent decades, Swedish hunters have had to settle for harvesting fewer animals. Even if it’s not the wolf itself that is disliked, the concern is often about the wolf’s impact on hunting. A moose calf taken by a wolf is, according to some studies, often over a month old, having followed its mother for weeks. For many hunters, the reduced opportunity to hunt moose is felt more keenly than the loss of the meat itself. The wolf’s tendency to attack hunting dogs causes particular worry and frustration.
Loose dog hunting for moose and hare hunting with scent hounds are traditional hunting methods that have declined in areas with wolves. The loss of the opportunity to hunt roe deer with one’s dog can, in the same way, be experienced as more difficult than the lack of roe deer meat for the household.
Apart from the increasing impact in recent years from wolves, bears, and lynx, the past decades have been very successful for deer game in Sweden. Moose and roe deer populations increased significantly at the end of the 20th century but had already begun to decline again before the turn of the millennium. Red deer and fallow deer are steadily increasing. Especially red deer have recently expanded their range northward.
Hunting is the main cause of death and the most important regulating factor for our deer species. They are primarily hunted during stand hunting, drive hunting, and push hunts. Dogs are often used: barking dogs for moose and driving or short-driving dogs for other deer game. Stalking is a common method, especially for roe bucks. Other cloven-hoofed game is hunted in the fall, usually in combination with stalking or stand hunting.
SUMMARY
- The sense of smell and hearing, and often also vision, are well developed in deer.
- The mating period in deer is called the rut.
- Deer are ruminants, which means they lie down from time to time and chew their food again.
- The antlers of deer are made of bone. They are shed and regrown each year. Among our wild deer species, only males carry antlers.
- Growing antlers are covered in blood-rich velvet, which dries and is rubbed off when the antler is fully developed.
- A deer’s antlers generally grow larger and more robust each year until the animal reaches peak age. It is then called a “capital” male. After that, the antlers shrink again, and the animal is considered to be in decline.
- By studying the teeth, it is sometimes possible to determine the age of deer. A moose calf has only four molars in each half of the lower jaw, while an adult has six.
- Hunting is the most important regulating factor for our wild deer populations and the leading cause of death.