Folks ask us, at different times throughout the year, “What has happened to all my hummers"? It seems that the number of hummingbirds we attract to our feeders varies greatly through the cycle of a year’s time. While they may have had record numbers feeding in their backyards for the previous week or two, now they hardly have any. Why is that? This is an accurate observation that has some logical reasons attached to it.
Some days or weeks, there seems to be more hummingbirds than most, while during other days or weeks their numbers are so small they seemed to have almost disappeared. What causes these fluctuations in their numbers?
A few explanations easily cover the majority of reasons for such population increases and decreases. Southern Arizona increasingly sees more species and numbers overwinter here. Keep in mind that our region is a destination point for many hummers that migrate south for the winter. While we do have several species that are seen here most of the year, some numbers within those species are resident and others migratory.
Anna’s Hummingbird is a good example of this. This species has been reported in our region throughout the year. However, whenever the migrating Anna’s join the resident Anna’s here their number swell. The migrants begin arriving in November and December. This is the time of year most birders notice the greatest number of Anna’s. By the end of December, the females have built their nests. By January, they are incubating eggs and by February, the fledglings are trying out their newly feathered wings.
Each season brings other migratory hummers to our corner of the state. Again, these are the times when overall populations of individual species are at their greatest. Most folks enjoy feeding hummers particularly at these times. Moreover, it is at these times that the birds are most cooperative and the least territorial. These are the times of year when it is easiest to see multiple birds using the feeding simultaneously. Of course, the strategic location of the feeders enhances this effect, not just during migration, but year round. Strategic location means placing the feeders in such a way that a hummer cannot see or defend any other feeder other than the one he/she is using. Locating them at differing heights above ground level also helps encourage cooperation and lessen competition.
The major reason for this is tied to weather conditions and an abundance of natural foods in the wild. Whenever we receive any substantial or measurable amount of rain or moisture there is usually an increase in natural foods that become available. Not only does the rain/moisture provide extra opportunities for fresh drinking and bathing water, but for a blossoming of natural foods. During fall, winter, and spring months every rain will produce catkins, buds, and flowers that hummers will investigate for both insects and nectar. During and after the monsoon season, insects hatch out in enormous numbers. Whenever there is a plethora of natural foods in the wild, the birds become less visible at our feeding stations and more obvious in the field.
Following any significant moisture; various shrubs, bushes, trees, and even cacti bloom. Hummers have been known to sip the juices from ripened fruits, especially cultivated fruits like peaches and wild cactus fruits. Sometimes hummingbirds are observed probing flowers that do not produce nectar. In these cases, they are investigating for minute insects that make up the vast majority of their solid food diet. Other flower species are rich in sustaining energy in the form of liquid nectar. Some flowers are rich in both nectar and insects. When these conditions predominate, we are apt to see less numbers of hummingbirds at our feeders.
One way to increase the number of hummers feeding in your yard is to have a fruit feeder or two nearby the nectar feeders. Using overripe fruit like bananas or peaches attracts a small horde of fruit flies. Once the hummers realize that the fruit is attracting insects, they will fly over to the fruit feeder and gobble up those tiny insects. In a few hours time a new generation of fruit flies replaces those previously eaten by the hummers. In this way, you can provide both the nectar and insects they need to thrive and keep them around longer. Otherwise, off they go, away from your feeders looking for insects in the wild.
To a lesser degree, bad weather conditions can keep hummers away from backyard feeding stations, too. Extended rainy weather, especially combined with cold fronts and windy conditions may cause hummers to find a protected location and wait out the bad weather. If you have a feeder well placed for protection against rain and wind, the hummers will use it whenever they need a little extra energy. Otherwise, they may spend most of their time perched, preening and resting in a safe and secure location. It is during bad weather days that they spend more time resting than foraging for food.
I sometimes notice that my feeders have remained full for a longer period of time than usual. This is usually the result of predators hanging around looking to make a meal of the birds. At our feeding station we generally have a host of predators that come regularly looking for nests, eggs, nestlings and fledglings, and even adult birds. We have a family of three roadrunners that are daily visitors. Seasonally, we have Kestrels, Sharp-shinned Hawks, and Coopers Hawks that love to dive bomb into the feeding stations, scattering all the feeding birds. We also have our share of bobcats, ring-tailed cats (civit cats), snakes, and coyotes. Most nights we have at least one of several owl species. Most bird species, even hummingbirds, will remain under cover whenever predators are present.
Of course, keeping your nectar fresh is critically important. Nectar should be changed, on average, at least twice a week. If nectar spoils, that is, if the sugars change into alcohol or the solution changes from clear to cloudy, the hummers that normally frequent the feeders will look elsewhere for fresh nectar. So, keeping the nectar fresh is the best way to insure that you don’t lose your hummers so easily.