More About Molting
Contributed by Jackie Allison. Thank you!

Rufous hummingbirds normally migrate through our area, but they usually don't stay long enough for me to see territorial behavior for any length of time. Our resident Anna's hummingbirds typically molt during a more tranquil time when there aren’t any intruders encroaching on their territory.

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Molting Rufous Hummingbird Photo Jackie Allison

Molting Takes Energy!
Molting takes a lot of energy from the already super-charged metabolism of a hummingbird. It also requires a larger amount of daily protein and minerals for the feathers to properly grow. To save their energy for hawking insects needed for extra protein and for hovering near flowers, hummingbirds seem to vocalize less and avoid displays of aggression unless necessary. That’s what this rufous hummingbird in molt was doing.

Allen's hummingbird sneaking in to take nectar from the Rufous hummingbird's territory. Green back and head.

War Games Before and After
The molting Rufous was easy to spot as he entered the games with a white chin, throat and chest. Staying to the outside of the battling group, his attempts to engage were weak at best. In the days that followed the unveiling of his male colors, I witnessed a change in his behavior almost daily. No longer was he on the outside of any hummingbird war games; the more color he could display, the bolder he became in guarding territory and approaching an intruding hummingbird or an unfamiliar human. Even the Allen's hummingbirds changed in their behavior when entering the Rufous’s territory--and the Allen’s are known for their tenacity.


One morning I was alerted by the higher pitched wing hum from an Allen's hummingbird. He was zipping in to take nectar from the Mexican bush sage inside the Rufous’s territory. I saw a different behavior from the Allen's as he tried to sneak in under the radar of the Rufous. No longer was his hovering methodical: grabbing a quick lap of nectar, lifting up, performing a half twist, surveying the area, then going on to the next flower where he’d again lift up, twist, survey in all directions. He never made it to the third flower! The Rufous hummingbird performed a zoom maneuver from the top of a cypress tree and chased the Allen’s green rump out of the area!


Learn More: See Jackie's Photo Journal.