July 23, 2012 report
Gorillas filmed performing amazing feat of intellectual ability
(Phys.org) -- Researchers working in Volcanoes National Park in Rwanda have filmed gorillas dismantling snares set by poachers to catch smaller game. Previously, anecdotal evidence had suggested that silverback gorillas had been seen dismantling snares. In this instance it was two young blackback, mountain gorillas that were involved. The team, part of the Dian Fossey Gorilla Fund's Karisoke Research Center, filmed first a silverback motioning towards the snare. Next, two young male blackbacks arrived on the scene, surveyed the situation, then proceeded to take apart the snare, avoiding being caught in it in the process.
Snares are small loops of plant leaves or rope, fashioned in a noose and laid on or near the ground. They are attached lightly to a bent bush and strongly to a tree. If an animal steps in the snare, the rope is released from the bendy bush causing the noose to tighten around the victim, who cannot run away because of the tether to the tree. Some victims are retrieved when poachers come to check their snares; others die from dehydration.
Those who work with gorillas have known for quite some time that the animals possess a brain that supports an intellectual level that far surpasses most other animals, including most other primates. In short, theyre really smart. Unfortunately, there is not much documented evidence to support such claims due to the few studies that have been done to measure it. This is because there are relatively few animals available in captivity that can be studied and because of the limited environment in which the animals live in the wild, which means, practically speaking, they dont often run into situations that require much brainpower. But when they do, researchers say, it can take your breath away.
To dismantle a snare, the gorillas pull the bent branch back, breaking it and releasing the tension in the rope. In the film, the two young gorillas get right to work indicating theyd done it before, and the researchers report that once finished the duo moved to another snare and disabled it as well.
The researchers also note that the snare destroying episode came shortly after the death of an infant gorilla that had become trapped in a snare; in trying to escape it had broken its shoulder which led to gangrene setting in.
Snares are common in protected parks in Africa as poachers set traps hoping to get some bush-meat either for consumption directly or to sell on the black market. The snares are not normally strong enough to trap a full grown gorilla or even a juvenile but present a significant threat to those still very small. The researchers report that the recent death of an infant was the second this year.
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