It's those spiky hot-wired things that I don't like. They are so unsightly. I suppose the ZSL thinks they need something to keep the apes away from the water's edge. But I can't believe they would be much deterrent if serious fighting breaks out and one animal runs in panic towards the water.
If you search 'London Zoo Gorilla Kindgom' on flickr, the oldest-dated are of it's construction and you can see how the moat is staggered so that the first third or so is shallow water, so hopefully the shock of entering the water would be enough to stop anything worse happening, although then the animal has to negotiate it's way back through the electric grasses....
It will be quite intriguing to see how this particular exhibit develops over the years, and whether or not the colobus monkeys will have permanent access to the kingdom. I still think that London Zoo should have built some sort of canopy for the gorillas.
