A thousand deer forty minutes from central London: what the rut is and why you must not approach

From late September two London parks host something other countries run special tours for: the red deer rut. It is free to watch and forty minutes from the centre. There are rules, and breaking them is genuinely dangerous.

When and where is the deer rut?

From late September to early November, in Richmond Park and Bushy Park. Between them the two parks hold more than a thousand free-roaming red and fallow deer.

The red deer is Britain's largest wild land mammal. During the rut a stag weighs around 350lb, reaches 30mph and can lose a third of its body weight in a fortnight. A dominant stag holds a harem of up to forty hinds.

Fallow deer do it differently: bucks do not hold harems but form a lek, where four or five males display to a group of around forty does.

What actually happens?

Roaring comes first, and it is the main tool: rivals size each other up by voice, and in most cases that settles it. If it does not, the stags walk parallel to one another, measuring up, and only then lock antlers.

What are the safety rules?

The Royal Parks put it briefly.

Keep at least fifty metres away. This is not politeness: an animal of a third of a tonne accelerates faster than you do.

Dogs on leads — but if a stag moves towards you, let the lead go: the dog can run, and you, attached to it, cannot.

Do not surround the animals or move in for a photograph. Selfies during the rut are exactly why the parks issue warnings every year.

When do the leaves turn?

In southern England the main colour holds from the second half of October to the first week of November. The exact date moves each year: early frost speeds it up, a mild wet October stretches it out.

More practically: the clocks go back on 25 October and it is dark by five. The after-work park window closes exactly at the height of the season — plan for weekends.

Where to go for autumn colour in London?

Free: Richmond Park (oaks and deer in one trip), Hampstead Heath with its view over the city, Kensington Gardens and Hyde Park, Greenwich Park, Bushy Park.

Paid: Kew Gardens. An adult ticket online is £25 in peak season, 2 September to 31 October, and £17 from 1 November; at the gate it is £28 and £20. Children aged four to fifteen pay £2 online, under-fours go free. Young people aged 16–29 and students pay £10 in peak season.

Two ways to pay less that not everyone knows. First, £10 Tuesdays: every Tuesday from 8 September to 29 December an adult ticket is £10. Second, Universal Credit recipients pay £1. Residents of Richmond, Kingston, Hammersmith and Fulham, Wandsworth and Hounslow get concession pricing.

What to take?

Binoculars beat a telephoto lens: they solve both the seeing problem and the staying-fifty-metres-away problem. Footwear for wet grass, a flask, and the knowledge that the parks are unlit — after the clocks change, leave before dark.

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