Website best viewed on a computer. It may freeze or crash on a mobile device.

Welcome! This website is a quick reference to the nocturnal flight calls of many North American birds.

Calls displayed here were collected via remote acoustic recordings. As such, there is some degree of uncertainty in their identification. Read more about this process on the About page.

Note: this website is best viewed on a computer. It may freeze on a mobile phone.

How to use this website...

By default, the website displays the common name, the scientific name, and a handful of example spectrograms for each species.

About spectrograms:

  • Spectrograms are labeled in milliseconds (horizontal axis) and kilohertz (vertical axis)
  • Click a row to display additional spectrograms. Click again to collapse the row
  • Click any spectrogram to listen to the sound. Click outside of the controls or hit "Esc" to exit playback

Use the Filter species functionality to limit which species are displayed:

  • Filter by any information available in the columns. For example, try...
    • Bioacoustic categories, e.g. zeep, double-banded upsweep
    • Taxonomic categories, e.g. charadriiformes, setophaga
    • Four-letter alpha codes, e.g. amro, oven
  • Press Enter/Return between each keyword to add it to the search
  • Click the "Filter" button (or use Tab + Enter) to apply the filters
  • Species that match any keyword will be displayed, e.g., searching for two alpha codes allows direct comparison of the species
  • Click the "Clear" button to display the whole list

Select the Denoised spectrograms checkbox to show denoised versions of spectrograms.

Use the Display columns selector to show or hide additional information about each species.