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.
Gettin' the Good StuffEver watch hummingbirds going about their daily lives? Well, sure you do, but I mean do you really study them. Do you ever watch the way hummers drink nectar and catch bugs? Do you ever wonder exactly how they do it?
Next time you are watching hummers, notice the way they approach each flower. Some blossoms, such as those of red salvia, are just made for a hummingbird. Others, such as those of trumpet creeper, seem somewhat less accommodating. Nevertheless, hummers have learned to reap the nectar from eachand many more.
Hummers pollinate many kinds of flowers, blossoms that have co-evolved with the birds to the benefit of each. But, the bird need not pollinate to be able to enjoy the reward. This is especially true for those flowers that are serviced by some other vector.
Bills of North American hummingbirds measure from just over half an inch to about an inch in lengthonly a couple of species have bills longer than an inch. Small blooms and those that open very flat do not offer much of a challenge to any hummers. And, trumpet-shaped flowers that are relatively short are just made to fit a hummingbird bill. A hummer can simply hover in front of the flower and insert its bill.
But, flowers that have an especially long tube or those that are tightly closed give the birds pause. The long, wide tube of trumpet creeper flower is easy enough for a hummer to approach, but in order to reach the nectar with the tip of its extensible tongue, the hummingbird must insert its entire head, thus blocking its view of the surrounding area. Momentarily, the hummer is vulnerable to any lurking predators.
Sometimes, hummers approach flowers from the outside, near the calyx or bract. The nectar is available to the birds without their contacting the sexual parts of the flower, provided the birds can penetrate far enough to reach the food. I watched several large hummingbirdsBronzy Inca, White-vented Plumeleteer, Long-tailed Sylphattack the large, tightly coiled flowers of a turk's cap growing on a roadside in Venezuela. Flowers of the turk's cap are hibiscus-like, but they never open.
These hummingbirds seemed to use their weight and flight momentum to pierce the base of each scarlet blossom with the bill functioning as a drill bit. Here in the deep south, the same flower is often used but in a different way. Sometimes, Ruby-throated and Rufous Hummingbirds probe between the calyx and the petals, but without the seeming force employed by their tropical kin. Other times though, I've seen them press their bill tips in along the filament as it protrudes from the never-opening blossom. The birds then lap the nectar that oozes down the stalk.
Sometimes sap replaces nectar in the hummingbird diet. Hummers find sap oozing up in sap wells made by sapsuckers on the trunks of trees. It's easy going for the birds. They just lap it up.
Bug-catching also has a couple of different variations. Often hummers are seen to trace delicate patterns in the air as they hawk minute, flying insects. The bird's forward motion and agile movements enable it to catch the bug in the back of its mouth, thus facilitating swallowing.
At other times, hummingbirds glean non-flying insects and small spiders from bark, twigs, and the undersurfaces of leaves. For this, they use the tips of their bills like fine forceps, deftly picking their prey off. It is a mystery how the hummers manage to convey the bugs from the bill tip to the back of their mouth for swallowing. Nevertheless, it must be effective as it is an oft-employed technique.
Hummers seem to be quite adaptable in their ability to secure the nourishment they need. They will sample many flowers, even if they are not specialized nectar-producers. In this way, the birds discover all the best sources of food.
Houston Area Readers: You are invited to the February 12 meeting of the Houston Audubon Society. My slide lecture "Hummingbird Gardens" will help you plan your yard to attract hummersjust in time for spring migration! Copies of my new book Hummingbird Gardens will be available. Join us at the Brown Educational Center of the Houston Zoo at 7:00 PM.
Copyright © 1997
Nancy L. Newfield