Cervus elaphus scoticus – subspecies found throughout Britain and the only species of deer that can be classed as indigenous. The species has been here in some form or another since Britain was joined to mainland Europe. The largest mammal in Britain it is also one of only two native mammal species found in Lewis. How they arrived on the island isn’t exactly clear but it is known that deer are extremely good swimmers and it may be possible that the deer on Lewis are related to those on Rum which may have gradually moved up through the islands.

 

Their name comes from the reddish brown colour of their coats in summer; however, in winter they can appear dark brown or grey. Cervus genus can be traced back 112 million years, it survived the ice age and there was a large population in heavily wooded post glacial Britain. Although they are historically a natural woodland dweller, they have been forced to adapt to a moorland environment due to the demise of pine woodland and as a result are smaller in size than those seen in other parts of the country. This is partly due to poorer quality nutrition available on open moor.

 

The average lifespan is 15 years. Hinds will normally breed between 3 and 13 years, males between 5 and 15 years of age. Death by old age is governed by the deers ability to consume food which is determined by tooth wear.

 

Females monopolise the better, relatively grass rich habitats whilst males tend to utilise poorer heather dominant areas. Grasses, sedges and rushes make up the summer diet, dwarf shrubs such as heather being more important in the winter.

 

The stags and hinds live in separate herds for most of the year. Stags can travel over large distances but hinds are ‘hefted’ which means that they remain close to their birthplace. In late summer the males move to where the hinds are and an increase in testosterone levels means they start to be come intolerant of each other. They break away from each other and take possession of and defend harems, this signifies the start of the breeding season which is known as the rut. During this time they become very noisy, roaring and bellowing and they spend a lot of time sizing each other up. Most of the time this is enough to deter a weaker opponent but occasionally fighting will occur, deer will lock antlers and push against each other until one gives up. Immediately prior to the rut the stag’s neck will visibly thicken and a mane will develop. This provides extra muscle and protection when fighting during the rut. The most successful stags will mate with around 15-20 hinds.

During the rut the stags don’t eat and they can lose around 20% of their body weight which dramatically affects their condition. This lack of condition and nutritionally poor grazing over the winter months leads to a high rate of male mortality over the winter.

 

Calves are born in June, dominant hinds tend to have male calves while lower ranking hinds will have female calves, this usually results in a slightly higher proportion of male calves – this is perhaps to compensate for the high mortality rate in winter.

 

Only stags have antlers and they are thought to represent dominance, particularly during the rut. Most stags will start to develop antlers at 2 yrs of age and they continue to grow in length, weight and number of points until they are 7-9 years old, although the development is influenced by food and shelter availability.

Antlers are cast when testosterone levels fall in march and april, older stags cast their antlers first which cause a brief period of unrest in terms of dominance. Almost as soon as they are cast, new velvet covered replacements begin to grow. Velvet is a soft, blood-filled bone forming tissue that is very sensitive, at this time stags will ‘box’ with their front feet to protect the antlers.

Once at full size the blood supply to the antlers is stopped and they begin shedding the velvet which becomes very itchy and uncomfortable, this is thought to be the time when stags cause most damage as they look for suitable trees, shrubs and other objects to rub against to remove the velvet.