Johannesburg - Environmental pressure group Baboon Matters has called on Environmental Affairs Minister Edna Molewa to intervene and place a moratorium on the killing of the animals by timber companies outside Sabie. Baboon Matters' Kathy Kelly said the group had discovered a "mass grave" between pine plantations in Mpumalanga, Netwerk24 reported. According to her, more than 4 000 baboons have been shot dead in the area since 2008. The baboons are "executed" after being lured with food into small cages and then shot dead at a close range in front of the whole troop.The Baboon Damage Working Group, established by the industry to find legal and ethical ways to limit damage by baboons, says the baboons sow havoc by pulling the bark off the trees. The pine trees then grow crooked and are worthless. This leads to damage estimated at millions of rand each year. Head of the group Dr John Scotcher said the situation is an example of the conflict between man and wild animals. "There are 40 ways of getting rid of baboons and this [to shoot them in a cage] is the most humane." Whole troops killedKelly said Baboon Matters had initially been part of the working group, but withdrew after it became clear to them that the forestry industry was manipulating and controlling it. She wants timber companies to monitor the baboons to establish why they are pulling the bark from the trees. People could also be sent into the plantations to scare off the baboons, she said. "This is just one of our suggestions which was ignored."Scotcher said the companies had at one stage considered electrified fences, but it wasn't viable. The group believes there is a "sweet substance" in the bark of a pine tree which makes it enticing for the baboons. "We are just trying to manage baboon numbers." Scotcher added that whole troops had to be killed because the little ones learnt from the older baboons to pull the bark off the trees.He said he knew nothing about a "mass grave" as the carcasses were normally burnt.