Visitors to the Phoenix Park have been told for years not to feed the deer, but they still do.
What many would regard as being a harmless activity is having a detrimental impact on the future of the herd of wild fallow deer that are much loved by the public, who regularly stop to take close-up photographs and selfies.
According to a study carried out by UCD and published in the Journal of Animal Ecology, the fawns of females that regularly beg for food from humans are significantly bigger than those that do not beg.
Lead author Laura Griffin said the process of natural selection would mean that over generations the whole herd would become more dependent on human feeding and, therefore, more aggressive.
Markets in Vienna or Christmas at The Shelbourne? 10 holiday escapes over the festive season
Ciara Mageean: ‘I just felt numb. It wasn’t even sadness, it was just emptiness’
Stealth sackings: why do employers fire staff for minor misdemeanours?
Carl and Gerty Cori: a Nobel Prizewinning husband and wife team
“In other words, in 10 years, if actions are not taken, you could end up with deer that consistently harass people... which clearly holds enormous risks for the people and animals involved,” she explained.
This is the first study of its kind in the world conducted into the relationship between wild animals being fed by humans and its impact on species.
The study is unique in that it focuses on wild animals that have regular access to people and approach them to be fed.
The Phoenix Park attracts about 10 million visitors a year and the deer are exposed to humans every day. The deer population in the park is about 600. The animals are entirely enclosed within the walls of the Phoenix Park and have no natural predators.
The deer were all tagged and observed over a period of 14 months between May 2018 and July 2019. Those that regularly interacted with humans for food were noted.
The fawn of females that begged for food were weighed over three successive fawning seasons (2018 to 2020) – 94 mothers and 134 fawns in total.
The study found that mothers that beg consistently are delivering fawns that are up to 300-500g bigger than those mothers that display reduced begging behaviour.
Ms Griffin said there had been incidents in other places where the interactions between wild animals and humans had changed the behaviour of animals for the worse.
In Japan’s Nara Park, home to 1,200 free-roaming wild deer, more than 200 people were injured by the animals in 2019.
The artificial feeding of rhesus monkeys in India, for example, has led to behaviour not normally exhibited in the wild, such as the animals attacking each other in a rush to obtain food from humans.
“Hand-feeding wild animals has become increasingly popular in recent times. In fact, videos and pictures of people feeding wildlife quite often go viral across different social media platforms,” she said.
“Nevertheless, it is of fundamental importance that we pause to explore how these interactions are affecting the wildlife involved.”
