Charity Blue Cross is warning dog walkers against taking animals to areas where there are wild deer during the rutting season this autumn.
The charity says it is important to keep dogs on a lead if deer might be present and stay as far away as possible.
A spokesperson said: “While stags and bucks battle to preserve their ‘hareems’, female deer are in season for just a few hours over the period and dogs or people coming between a male and female deer in season are in serious danger of being injured.
“There is also a risk of getting caught in the crossfire when male deer are fighting intensely or chasing each other away.”
Claire Stallard, Animal Behaviourist at Blue Cross, added: “There will be increased activity during the rutting season and your dog may become excited by the extra noise, smell and movement, so it makes sense to keep your distance.”