Sambar is a large deer native to Southern and Southeast Asia and is scientifically known as Rusa unicolor. The term Sambar is sometimes also used for the Philippine deer and the Rusa deer. The size and appearance of this animal has led to a number of taxonomic confusions. Sambar may attain a height of 102-160 centimeters and weighs about 546 kg. Head and body length may be 162-246 cm with a tail of 25-30 cm. western subspecies is somewhat larger as compared to that of the Eastern subspecies.
The antlers are large and typically rusine and the brow tines are simple and the beams are forked so they have only three tines. The antlers may be 110 cm in length in adult animals. Like all the deers only males bear antlers. The fur may be yellowish brown to grey-black in colour. Some species have a chestnut coloured mark on the rump and underparts. They have small and dense mane found only in males. The tail is somewhat longer than deer and black above but whitish on the underside. Adult males and pregnant or lactating females have a prominent hairless, red spot on the underside of the throats. This spot sometimes oozes a whitish glandular secretion.
Sambar inhabits much of the Southern Asia, mainland Southeast Asia, Taiwan, and the islands of Sumatra and Borneo in Indonesia. They can be found in the habitats ranging from tropical seasonal forests, subtropical mixed forests to tropical rainforests. They dwell at places far from water and are hardy animals. They prefer dense cover of deciduous shrubs and grasses but the exact nature varies with the environment. They are found in woodlands and feed on a wide variety of vegetation including grasses, foliage, browse, fruit, and water plants, depending on the local habitat. They can be preyed by sympatric mugger crocodiles. Leopards and dholes will take young or sickly deer. They are favourite food items for tigers and Asiatic lions. Large herds of these animals are well protected in national parks and nature reserves in India, Sri Lanka, and Thailand. In Taiwan the antlers of sambar and sika deer are highly priced.
They are nocturnal or crepuscular animals. The males live alone for most part of the year while females prefer to live in group which may be comprised of about 16 individuals. In some areas the group of females may be small consisting of only 3-4 individuals including her most recent young, a subordinate and an immature female. This is an unusual pattern among these animals as most of the deer tend to live in large groups. They often congregate near water and are good swimmers. Like all deer they are calm and quite animals but the males may bellow during the rut. All individuals can scream or produce high or short pitched voices when alarmed. They generally communicate by scent marking and foot stamping. The adults wallow and dig their antlers in urine soaked soil and then rub it on the tree trunks. They are capable of bipedalism. The male can also psray the urine directly over his face with the help of highly mobile penis. Although the female lacks antlers but she is capable of fighting and defending her young one from the predators. When attacked by domestic dogs they lower their mane and lash it against them. When sensing any danger they start stamping their feet and produce sounds known as belling.
They generally reproduce throughout the year but the oestrus lasts for about only 18 days. Rutting is a very usual feature in these animals. The male establishes a territory and then attracts the female but does not form a harem as found in all stags. The male stomps on the ground, makes a discrete patch and often wallow in mud and also displays its fur colour which is darker than the females. The male often bellows. The male also defends the territory. The female signals the male when she is ready to mate. Gestation period lasts for about 8 months or it may be slightly longer. Generally a single calf is born and the percentage of birth of twins is only 2%. The young weighs about 5-8 kg at the time of birth and may be spotless but in some species spots are present which vanish after few days. They start taking solid food when they are 5-14 days old and begin ruminating at the age of one month. They have an average lifespan of about 12 years in the wild but when kept in captivity they can live up to 28 years.
The subspecies of sambar in India and Sri Lanka are the largest of the genus with largest antlers both in size and body proportion. Fossil record suggests that they evolved during Pleistocene. They have entered the category of endangered and are protected in national parks and nature reserved in different parts of the world.