Contributed by Alexis Billings
My name is Alexis Billings and I am a PhD candidate in the Organismal Biology and Ecology program in the Department of Biological Sciences at the University of Montana. I study animal behavior and communication. My research is focused on alarm calls, which are acoustic signals animals give in response to predators. Alarm calls are varied in their acoustic structure to obtain optimal transmission and to encode important information about predator type, predator threat level and even predator behavior. The acoustic structure of an alarm call can have radical effects on how well an it travels over long distances and through different habitats. I measure the loss of energy of different types of alarm calls over different distances and in different habitats. I compare these measurements to the loss of power calculated from wave transmission equations used in physics. I can then estimate the transmission properties of different habitat types and pair acoustic structures to certain habitat types. This combines biology and physics and gives us an idea of how animals are making sure their signals are being received. Alarm calls can also encode important information about predators. This information is used by numerous individuals that span species and even taxa in what is called a communication network. These communication networks add a new level to our understanding of how species are interacting and even cooperating to avoid predation. My research has found that communication networks in western Montana include multiple species of birds such as chickadees, nuthatches, and woodpeckers, as well as red squirrels. I have also found that the information travels incredibly fast within a communication network reaching numerous individuals in a matter of seconds. Understanding how animals communicate about danger involves understanding the physics of sound and how sound travels as well as how animals are really using these signals to avoid predation.