People are being asked to keep at least 50 metres away from the deer in the Phoenix Park in Dublin.
Over lockdown, the park experienced increased visitors, with some attempting to feed and take pictures with the animals.
The Park's Superintendent Paul McDonnell has reminded people to remember wild deer are not the same as Disney's Bambi.
"Deer have been the subject of many books and films and have a special place in our hearts."
"However, these depictions often make them appear domesticated which they are not."
OPW calling on the public NOT to feed the wild Deer in Phoenix Park this Christmas.
To discourage visitors from feeding the wild deer, a number of post boxes for children to drop off their letters to ‘Rudolf' are located in the Park, Full details: https://t.co/Uu5TQiFxsK pic.twitter.com/FCRMkYUcik
— Phoenix Park (@phoenixparkopw) December 2, 2020
Feeding the animals can cause malnourishment, as the herd tend to graze on grass and foods such as carrots or bread are harmful.
However, the park's elves have installed special letter boxes where children can send letters to the head reindeer, Rudolf.
Superintendent McDonnell said "We've set up post boxes in a number of different locations around The Phoenix Park so that instead of maybe coming with carrots to the park children can bring a Christmas letter."
