Despite growing outrage from animal activist groups, local environmental scientists have praised the scheme announced last week, which intends to exterminate 90 per cent of the iconic Snowy Mountains brumbies.

Charles Sturt University senior professor in ecology David Watson said while he understood the views of animal activists, the extermination of the horses was necessary.

“I’m sympathetic to the views of animal activists and culling is not what anyone wants to do, but it is the most humane and responsible course of action to get rid of these pests,” he said.

Professor Watson said people against the cull didn’t understand the extent of the harm brumbies had on the fragile environment.

“The damage is done in ways people don’t even realise,” he said. “There are no native animals with hooves, so through their feet and trampling these animals are destroying whole ecosystems and decimating the habitats of other organisms.”

Many animal welfare groups have called for the capture and rehoming of the brumbies, rather than a “mass culling”, but Professor Watson said the number would not be enough to begin environmental regeneration and could be more traumatic for the animals than euthanasia.

“These are wild animals, so trapping and capturing them causes serious stress and trauma for both the animals and humans involved,” he said.

When asked about cruelty concerns raised by animal welfare groups, NSW environment minister Mark Speakman said the plan outlined a range of “humane control methods”, including trapping, mustering and ground shooting as a way to decrease the population.

“The government has ruled out aerial shooting, brumby running and roping due to animal welfare concerns,” Mr Speakman said. “We have taken advice from an independent expert panel whose members include the RSPCA chief scientist.”