Figure 2. Illustration of the drop-netting method for catching cliff swallows at a bridge colony: (a) the net is carried onto the top of the bridge, (b) dropped over the side to capture birds, and (c) carried off the bridge for processing of birds.

The colony pictured is Beckius. A video illustrating drop-netting of cliff swallows at CR4 is available at http://www.youtube.com/watch?v=kyfe5Sg9t0Y.