Campephilus Woodpeckers

Identifying double knocks made by an Ivory-billed Woodpecker is tricky. The sound is described in the scientific literature by people who heard the display prior to the 1950s, but there are no known recordings with which to compare recent recordings from the Big Woods. Researchers use recordings of double knocks made by other woodpeckers in the same genus, Campephilus, as a best approximation of what an ivory-bill display drum might sound like.

Choose "Interactive Analyzer" to explore the sonogram and see it scroll across the page as the sound plays. When viewing the sonogram, click on the circled i for information about how to use the sonogram features.

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Pale-billed Woodpecker double knock - Interactive Analyzer or Simple Sounds

Powerful Woodpecker double knock - Interactive Analyzer or Simple Sounds

Compare this sound with other double knock sounds:

Audio Playback Requirements

Two audio formats are in use:
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