Wellington Zoo's "extremely difficult" decision to euthanise a group of four male baboons has come under fire from Animal rights group Save Animals From Exploitation (SAFE).
The zoo said today the decision was made after the welfare of the animals was compromised following a breakdown of their social structure.
The breakdown of the Hamadryas baboons' social structure has led to a "critical risk situation" for the primates, including serious fighting causing injury and high levels of anxiety, Wellington Zoo chief executive Karen Fifield said in a statement.
"We have an important duty of care to ensure that all animals we care for at the Zoo experience positive welfare and unfortunately for these baboons this is no longer the case. When it comes to a decision like this we need to make a decision before the animals begin to suffer, in this case it is a matter of urgency," Ms Fifield said.
"This is not a decision that we have made lightly and it is very tough on all of us, but particularly those who dedicate themselves to caring for our animals. However, after extensive international research, lengthy discussions with our animal care, animal science and veterinary teams and other animal welfare experts, we are certain this is the kindest and most humane action we can take. Baboons are a social primate and the current situation is untenable for these animals."
Various options, including rehoming the primates through the breeding programme, were explored but were either "not possible, or would not improve the welfare state of the baboons", she said.
"It's an incredibly sad day for all of us at Wellington Zoo, and although it's been a very distressing decision to make, our utmost regard for the animals' welfare made this decision necessary.
"It is our ultimate responsibility to ensure our animals live good lives without suffering. Our Zoo team and our community loved the baboons and we will all miss them terribly."
Animal rights group Save Animals From Exploitation (SAFE) responded, saying the decision "again highlights the inherent cruelty of animal captivity for entertainment".
"Social structures suffer in enclosed environments and could be attributed to fighting and anxiety for animals. When these social systems break down and there is fighting, vulnerable animals are not in a position to be able to escape as they would in the wild," SAFE chief executive Debra Ashton said.