The New York Times: To study nest predation, scientists first have to find the nests on the tundra, which is not easy … the conservation society’s scientists are relying more and more on an enormously helpful tool: camera traps. Such devices, which are motion-sensitive, collect pictures of animals as they pass in front of a camera’s lens. That means that scientists don’t even have to be present to record a predation event. Witnessing such an event in person is quite rare; predators can find a nest, consume its contents and leave in a minute’s time. With the remote cameras, we can easily identify the predator species that are doing the most damage to the nests.

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