Photos of the incident in question circulated on Twitter. In them, the names “Camille” and “Julien” can be seen marked on the endangered animal’s back.
In a Facebook post, officials at the La Palmyre Zoo said they are “obviously outraged by the stupidity,” but that the names were “quickly erased with the help of a brush and did not cause any discomfort to the animal.”
Zoo director Pierre Caille said the visitors used their nails to scratch through a layer of dirty and dry skin on the rhino’s back.
“The animal may not even have realized,” he told Agence France Presse. “We quickly brushed the writing away and there was no harm to the animal.”
Most visitors touch the animals with respect when they choose to be near their enclosure wall, park officials said.
La Palmyre is one of the most visited zoos in France.
According to the AFP, French wildlife protection agency La Biome said the zoo “fell short of standards” by allowing “this type of interaction.”
The zoo says it remains committed to the safety of its animals, and that it remains “vigilant as to the behaviour of visitors within the park,” through signage and verbal reminders via microphone all throughout the day.
Caille told the AFP that they will consider installing video camera surveillance to catch future offenders, but they don’t “want cameras everywhere.”
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The photos ignited outcry on Twitter, with one user writing: “Shame on these people, they deserve the same thing! When we see the stupidity of these people, we understand better why the world is moving so well.”
“We must denounce this act of human stupidity,” another tweeted, while another person suggested that the culprits had been “badly raised.”
Few rhinos currently live outside of captivity due to poaching and habitat loss, according to the World Wildlife Fund.
In total, there are five species of rhino: Sumatran, Javan, black, white and greater one-horned rhino.
There are only three remaining northern white rhinos. They’re currently kept safe at the Ol Pejeta Conservancy in Kenya, while black rhinos have doubled in number over the past 20 years.
The Greater one-horned rhino is a vulnerable species that lives mostly in northeastern India and parts of Nepal.