Nancy Newfield Nancy L. Newfield has been watching hummingbirds at her Louisiana home and lots of other places since 1975. Nancy lost her amateur status years ago, and now writes and lectures on hummers. She is co-author of Hummingbird Gardens, reviewed elsewhere on this site. Nancy is also a licensed hummingbird bander and a recognized authority on hummingbird distribution, behavior, and taxonomy.

March 1998

Sky Divers

Up, up, up he goes! A feathered comet climbs skyward. Hovering momentarily, the hummingbird then plummets toward earth at lightening speed, pulling up just as a crash seems inevitable. Electric charges fill the air.

Hummer high jinks? Not quite! This guy means business. He is asserting his territorial claim and letting the ladies know he's available as well. And, he's not wasting any time.

Consummate aerialists, hummingbirds use towering pendulum displays for more than one purpose. The high dives so characteristic of male hummers are effective to let other hummers know who is boss, as in "this land is my land!" Yet, these dazzling maneuvers also attract and enchant eligible females, out looking for a mate.

The displays trace gigantic "U"s or "J"s in the air. The exact shape and dimensions are determined by the male's species. Anna's, Broad-tailed, Black-chinned, and Ruby-throated Hummingbirds make "U"s, while Allen's and sometimes Rufous Hummingbirds perform big "J"s. More often, the male Rufous traces a large "O". These stylized flights are thought to be the isolating barriers that prevent females of one species from mating with males of other species. Females do the choosing!

But, the towering "U"s and "J"s aren't the only kinds of flights used for courtship. They are just preliminary to a closer, more intimate flight called a shuttle. For the shuttle, the male performs an intense back-and-forth flight or a small shallow pendulum flight within a foot or two of the female that has indicated a readiness for mating by remaining in the territory of the males intimidating display. It is here that he really turns up the heat!

Males are the only ones to make the flight displays. Immature males sometimes expend a lot of energy practicing their macho arts on the wintering grounds, though these flights seem to lack the passion of springtime displays. Adult males, having perfected their technique, seem content to save the strenuous sky dives for defending their breeding territories.

Often, hummers—all ages and both sexes—are seen flying up-and-down or round-and-round with their chests closely appressed, flights that are frequently misinterpreted as courtship, but these are territorial contests. Females and youngsters can be just as aggressive as full-plumaged males at times!

Most of the time, courtship displays are performed at the male's feeding territory, usually a patch of flowers that are rich with nectar. The female enters the male's space. But there are always variations on a theme. The male Lucifer Hummingbird seeks out the female on her nest and displays to her there.

Mechanical sounds and vocalizations round out both the pendulum flights and the shuttles, these sounds being species specific, yet another barrier to interbreeding. These guys really don't want to be ignored!

Happy New Year and Happy Hummingbirding!

Copyright © 1998
Nancy L. Newfield
Casa Colibri
Metairie, LA

Previous Hummer Notes columns: July 1996 | August 1996 | September 1996 | October 1996 | November 1996 | December 1996 | January 1997 | February 1997 | March 1997 | April 1997 | May 1997 | June 1997 | July 1997 | August 1997 | September 1997 | October 1997 | November 1997 | December 1997 | January 1998