Behavior can also help identify the Anna’s. It is one of the two North American hummers that are known to sing. Costa’s also sings. Listen for a coarse, raspy series of squeaky notes, uttered from a perch. When displaying in either a courtship ritual or an intimidation flight, the male climbs to a height almost out of sight. He dives vertically at a tremendous speed and levels off just above the ground and in front of a calmly perching female. At the bottom of his plunge, he spreads his tail feather and sharply cries peek! During the courtship dives, the males achieve wing beats up to 200 times per second! And, their dive speeds have been recorded at 65 mph.
The sounds most North American hummingbirds make is caused by air moving through the wing feathers. The historical record identifies their sounds as a buzzing or humming sound – hence the name. If hummingbirds are deficient in any way, it is in their limited ability to vocalize. Only a few species, chief among them the Anna’s and the Costa’s, produce anything more than simple, high pitched twitters. The syrinx (voice box) is placed far forward in the trachea (windpipe), making the bronchi unusually long. The major muscles that connect the sternum (breastbone) and the trachea in most birds to control vocalizations are completely missing in hummers, although 2 special intrinsic muscles exist. Feather vibrations produce the instrumental sound that the name implies.
From the historical record comes another example of Anna’s behavior. In 1910, J.H. Bowles, from Santa Barbara, California, reported an interesting hummingbird-snake incident. “I noticed a female Anna’s making repeated dives into the center of a wild rose bush. I looked for what had her attention and found a four foot snake. With the hummingbird watching from a neighboring live oak perch, I killed the snake. Its stomach contents showed it was guilty of nothing more than eating a lizard”.
“I tossed the snake on the ground near the bush and moved a short distance away to see what the hummer would do. Almost immediately the Anna’s darted down and hovered over the snake. Her head was bent down. Her caution, in contrast to normal female Anna’s hummingbird behavior, showed she may have appreciated her danger. Hovering from point to point, the hummingbird examined the snake from several angles before whirling up into the air, and away. Her behavior toward the dead snake was so different from when it was alive I believed the hummingbird was satisfied the snake was dead, therefore discounting it as a problem”.
Anna’s hummingbirds are known to eat a wide variety of foods in relation to other hummer species. In part, this is what enables them to occupy a variety of habitats and elevations. Hummingbird foods are clearly divided into two types: carbohydrates, mainly from flower nectars but also from the juices of fruits and berries; and proteins, from the minute insects and spiders they consume.
Animal protein and amino acids are derived from the wide variety of insect they consume. Insects comprise approximately 15% of their diet and are essential to their good health. Anna’s forage for insect food in several ways. They can often be seen perching on a high, exposed branch and, in the manner of flycatchers, will swoop off the perch in a circular fashion and pick off tiny insects in mid-air. Sometimes they will dart about furiously in a swarm of gnats or other small insects for several minutes at a time. In these chases, the Anna’s are extremely successful hunters, rarely missing their target. If they do miss their prey on a first attempt, they will continue to pursue that individual insect until it is caught and consumed. They also glean plant leaves (the underside of leaves are where small insects gather to rest in shade and avoid many predators) and stems for tiny insects like treehoppers, fruit flies and other types of small flies, gnats, mites, etc. Insects are also attracted to both nectar-producing and non-nectar flowers and the hummers will hunt them down wherever they can be found. Among trees that Anna’s will glean for insects up and down the bark, the most important are the oaks, eucalyptus, elms and willows. They regularly visit spider webs for silk during the breeding season and otherwise consume the spiders themselves as well as other small insects caught in their webs. Spiders seem to be their preferred food, especially small and baby spiders, which researchers estimate at between 60 and 80 per cent of their daily solid food intake. On rare occasions, the bird may find itself tangled up in the webbing, which could result in their demise if they can’t free themselves before using up all their energy reserves. Several accounts have been reported of Anna’s following sapsuckers and foraging on both the sap itself (a good source of iron and protein) as well as other small insects stuck in the sap.
Plant nectars comprise the majority of the Anna’s diet, usually accounting for 85% of their total food intake. Bright red tubular flowers are most sought after but other flowers in the warm ultra-violet spectrum (yellow, pink, peach, orange, red, and purple) will also be used. The list of flowers which Anna’s take nectar from would be enormously long, but there are several which seem to be preferred when available. Among the most desirable nectar sources are gooseberry, desert paintbrush, flowering eucalyptus, and tree tobacco. Tree Tobacco may be the most important of all as it has nectar-producing flowers year round, is a host plant for a wide variety of minute insects, and has branches that are very appealing for perching, roosting, and nesting purposes). Anna’s have also been known to feed on the juices of ripe fruits and berries. Oftentimes, when other types of birds visit fruit trees or orchards, those birds rarely consume an entire fruit. Usually, they will peck an opening, or perhaps the fruit split apart upon ripening, and leave the rest after taking only a small amount. The Anna’s will then come in and, if juice is present, partake in sipping some of that juice. This has been observed in citrus orchards and with other fruits like persimmon and various cactus fruits.
Grit/Minerals in the Diet
Unlike most hummingbird species, female Anna’s have been observed consuming grit – which contains additional minerals necessary in their diet. These observations were all made during nesting season when added calcium is especially important in producing thicker, stronger egg shells and rapid bone development of the young. Females have been observed hovering close to the ground picking up small grains of sand and soil. Sometimes they would plunge their bills directly into loose sand and soil. Other observations showed that the females would actually land on the ground and forage instead of the usual hovering.
In backyards, these hummers are quickly attracted to nectar feeders. It is important to use only ingredients that are found in nectar-producing flowers, not just simple sucrose (table sugar) and water. The natural nectar found in their favorite flowers is actually a glucose-based nectar, composed of three primary plant sugars – dextrose, fructose and sucrose. To provide the ultimate nectar, the one that most closely approximates nature’s nectar, try our new and improved hummingbird nectar. Ounce for ounce, it is also the least expensive and most cost-effective nectar on the market. We now have it available in multiple different sizes. We are aware that many folks have attracted hummers to feeders that contain solutions that are less than preferable, and certainly far removed from what nature intended for them to drink. We try to educate our customers to provide quality nectar which is inexpensive and, best of all, causes no harm.