Figure 1. Position of on-bird microphones on freely behaving zebra finches.
Close-up pictures of backpacks fitted on zebra finches in an aviary. The visible white ‘backpack’ contains a microphone (at the bottom), a radio transmitter, and a battery. It is placed on the bird's back (centre of mass) in a way that the microphone faces inwards, that is, towards the bird's body. Unlike the backpacks, harnesses disappear under the birds' feathers (left and right panel and Video 1), therefore, to demonstrate how they were fixed on the birds, the two silicon loops around the head and the abdomen are represented by dashed lines in the left panel. They were closed at the front of the bird with a small knot.
Figure 1—figure supplement 1. Group housing.
Overview of experimental room including aviary and technical set-up.