Many animals produce alarm calls when the perceive danger. Birds are exceptionally good at detecting predators, and they produce a variety of important alarm calls. These alarm calls can be passed along by individuals of their own species as well as many other species. We know little about how different species participate in these communication networks, nor how far and fast information travels. Using robotic raptors, playback experiments and large satellite-synchronized recording arrays, we have been testing ideas about communication networks in the wild. Our dynamic maps of the “infoscapes” in large forests show that the transmission of information about predators can be impressive: many species of birds and mammals can participate in communication networks, and waves of information about predators can spread very fast.