The “How to Read Spectrograms” section of this blog is in desperate need of an upgrade, so today I’m starting a series of posts to help people describe and visualize sounds as simply and clearly as possible.  Our first topic: pitch patterns.

To identify birds, you don’t need musical training.  You don’t have to name the notes that a bird is singing.  You only have to recognize whether the pitch of a sound is rising, falling, or staying the same.  Five simple patterns allow us to describe most sounds:

• Monotone sounds do not change in pitch, and appear horizontal on the spectrogram.
• Upslurred (or rising) sounds rise in pitch, and appear tilted upward.
• Downslurred (or falling) sounds fall in pitch, and appear tilted downward.
• Overslurred sounds rise and then fall in pitch, appearing and sounding highest in the middle.
• Underslurred sounds fall and then rise, appearing and sounding lowest in the middle.

Let’s listen to some examples.

Monotone sounds

These sounds are characterized by horizontal lines on the spectrogram. Even if those lines are very short (as with the Townsend’s Solitaire call), it’s still easy to hear that the sound isn’t going up or down, just remaining on the same pitch from start to end.

Upslurred sounds

Listen to these sounds and practice hearing how they rise in pitch.

Downslurred sounds

Listen to these sounds and practice hearing how they fall in pitch.

Overslurred sounds

One of the most common pitch patterns in bird sounds is the overslur, which rises and then falls in pitch.  These sounds are often mistaken for upslurs or downslurs, so listen carefully to hear both the initial rise and the ending fall.

Underslurred sounds

This is not a common pattern, but when heard, it is distinctive.

These five basic pitch patterns are the starting point for talking about the different types of notes that we hear from birds, but there’s much more to discuss.  Next up, we’ll discuss the four basic patterns of repetition and speed.