When Is the Red Deer Rut? Roaring Stags and Antler Clashes

When does the red deer rut start and end?

The rut is triggered by shortening days. As daylight falls in late summer, stags’ testosterone rises, their antlers harden and they strip off the velvet skin. By September their necks swell, many grow a shaggy mane, and they start leaving the bachelor groups they lived in all summer.

Timing shifts a little with latitude, altitude, weather and the age of the stags. Prime stags usually rut at the peak, while young and old stags tend to hold hinds later in the season, when the strongest males are worn out.

Why do red deer stags roar?

A stag’s roar is a deep, rolling bellow that can carry far across a glen. It does two jobs. It warns rival stags that the harem has a strong defender, and it helps attract and keep hinds. Long-term research on the Isle of Rum in Scotland found that rival stags roar back and forth, and that a stag tends to back off from a rival that roars faster than he can. Because roaring hard is exhausting, the roaring rate is an honest signal of a stag’s condition.

Roaring is most intense around dawn and dusk, but at the height of the rut stags may call all through the night. Red deer roar, while their North American relatives, elk, make a high, whistling sound instead. Compare the two in why do elk bugle?

Parallel walks and antler fights

When roaring does not settle a contest, two stags often perform a parallel walk. They stride side by side, a few meters apart, stiff-legged and watching each other. This lets them judge size, antlers and stamina up close. Many contests end here, with one stag walking away.

If neither gives way, one suddenly turns and the two lock antlers, pushing and twisting to force the other backward or off balance. Fights usually last less than a minute. The loser breaks off and runs, and the winner rarely chases far. Even so, fighting is risky: some stags break antlers or suffer wounds, and a small share are seriously hurt each year. This is why so much of the rut is about display rather than combat.

Rutting stags also wallow in peaty mud, spray urine on their bellies and necks, and thrash vegetation with their antlers. The smell and dark, muddy coat advertise their status to hinds and rivals.

Harems and mating

A mature stag gathers a group of hinds, called a harem, and herds them together while keeping other stags away. Harems usually number from a few hinds to around 20, sometimes more. Younger stags hang around the edges, hoping to slip in and mate while the harem holder is busy.

Each hind is receptive for only about a day. If she does not conceive, she can come into season again about 18 days later. Because so much of a stag’s time goes into guarding and fighting, harem holders barely feed and may lose up to around a fifth of their body weight by the end of the rut. A stag in poor condition may not last until the peak.

On Rum, stags were most successful at around eight years old. Stags younger than about five rarely held harems, so most males have only a few good seasons to breed.

Where can you watch the red deer rut?

Red deer rut wherever they live, and many sites in Britain and Europe are famous for it:

• Scottish Highlands and islands, including the Isle of Rum, where red deer have been studied since the early 1970s. Read more in wildlife of Scotland.
• Exmoor in southwest England, home to a native population.
• Richmond Park and Bushy Park in London, where large herds live close to the city.
• Killarney National Park in Ireland, with the country’s oldest native herd.
• Veluwe in the Netherlands and Jægersborg Dyrehave near Copenhagen in Denmark, both popular autumn deer-watching areas.

Choose a calm morning or evening, use binoculars, and watch from paths, hides or a car. Rutting stags can charge if they feel threatened, so keep at least 50 m (about 55 yards) away, keep dogs on a lead and never stand between two stags. If anyone is seriously hurt, call 999 in the UK or 112 in the EU.

How does the red deer rut compare with other deer?

Each deer species has its own breeding season:

• Fallow deer rut in October, with bucks groaning from fixed rutting stands.
• Sika deer rut from September to November and give an eerie, high-pitched whistle.
• Roe deer rut in summer, mainly from mid-July to mid-August, but the embryo pauses its development until winter. See the roe deer profile.
• Elk in North America rut from about early September to mid October.

For more about the animals themselves, including how big stags get and why they need so much stamina, see the red deer profile.