If you've ever wondered why all the tigers look so surprised in that issue of National Geographic, you only need to look as far as the modern-day camera trap. Armed with motion sensors and flash photography, these traps* sit silently in the jungle, waiting for a passing otter or a snooping tiger to set them off. Many also give off a pre-flash first, as a bit of a mechanical, "Smile for the camera". Their effectiveness is proven, both for wildlife photographers and conservationists alike. Perhaps most importantly, they also allow people to monitor habitats without disturbing the normal activities of the wildlife. Some time ago, I wrote about research conducted at Michigan State University, East Lansing, which discovered that Nepalese tigers had shifted their active hours to avoid people. You can read about it here.