Old Bird provides resources for anyone interested in establishing an acoustic station to monitor night flight calls of migrating birds. The information here will guide you through the steps for setting up such a monitoring station.

The core of the station is the microphone. A simple microphone design is available here that can be built in less than 2 hours for under ~$35 US. The microphone is typically mounted on a rooftop and an audio cable brings the signal into the building below (e.g., residence or school) to one or more recording devices. The primary recording device is either a hi-fi VCR or an IBM compatible computer. The latter uses specially designed software to automatically detect and extract night flight calls of migrating birds. The software copies the detected sounds to files in a folder on the computer’s hard drive. These files can then be quickly browsed and sorted using another software program called Glassofire that creates time-frequency pictures of the sounds. These "spectrograms" allow visual inspection of the sound and easy to distinguish between bird calls and environmental noise. Once the bird calls are sorted from extraneous noise detections, they can then be matched to species or species complexes using the night flight call library.

A simple microphone system can be built to help tune in and amplify bird migration call notes. You can do this for listening pleasure or you can go a step further and follow directions provided on this website to document the number of calls and species of birds flying over a specific location. Once your recording system is functional it can be integrated into regional networks of recording stations to help produce a bigger picture of bird migration and begin logging data on regional bird migration patterns. Long term monitoring may provide a unique index for changes in bird populations.