Why Do Hummingbirds Fight So Much?

For hungry hummers in need of nectar to fuel their high-speed lives, territorial disputes can get ugly.
Two hummingbirds on a small branch fighting with each other.
Hummingbirds of the genus Selasphorus. Photo: Jerome Gaw/爆料公社 Photography Awards

Anyone who has carefully observed a hummingbird flitting about a nectar feeder or a patch of flowers has likely seen it happen. One moment, the graceful aerialist is darting between bright blossoms, jittery but tranquil as it laps up sugary juices. Then, suddenly, all hell breaks loose when a second bird approaches. In a flurry of chittering, gorget-flaring, and dive-bombing, the featherweights duke it out. The furious bout lasts only a few seconds but is long enough to declare a loser and send them zipping away.

Such violent outbursts may be surprising given the minute size and delicate appearance of these dazzling birds, but there is good reason for their aggression鈥攖heir sweet tooth, says Scott Weidensaul, an ornithologist and author who has studied and banded the winged gems. Hummingbirds are highly dependent on nectar, the sugar-loaded syrup that plants generate to entice pollinators into spreading the plant鈥檚 genes. It鈥檚 the rare food that provides enough energy to fuel a hummer鈥檚 constantly whirring wings and rapidly firing heart. 

鈥淭hey鈥檙e burning such extraordinary amounts of energy,鈥 says Weidensaul, noting that some species like the Blue-throated Mountain-Gem can reach heart rates of more than 1,200 beats per minute. 鈥淚 can鈥檛 imagine they would be able to maintain the energetic output that they do without that sugar water.鈥

When the stakes are that high, it鈥檚 little wonder that hummingbirds are protective of their food. To make matters even more dire, nectar is often hard to come by. 鈥淭here鈥檚 only so many flowers out there,鈥 Weidensaul says, and each one provides a limited supply of sugar before needing time to generate more. 鈥淭here鈥檚 a lot to be said if you can figure out a way to dominate that resource for yourself.鈥 For hummingbirds, this means fiercely defending their territory.

When the stakes are that high, it鈥檚 little wonder that hummingbirds are protective of their food.

When a territorial hummer spots an uninvited guest, it wastes little time persuading the interloper to move along. Some approaches that might appear less aggressive to human observers鈥攄isplays where the defensive bird fans and flashes its tail at its opponent while vigorously chattering, for instance鈥攁re unambiguous signals to other hummingbirds: You are not welcome. Other threats, like plunge-dives, stabs, and grabs with the bill and feet, are unmistakably antagonistic. Adult males are typically the most vehement in their defense and will respond more swiftly and harshly to other adult males, but hummers of all ages, sexes, and species will defend food resources. When birds do come to blows, the hopeful challengers almost always defer, unwilling to risk the strain of a full-fledged fight.

Fights over flowers and their limited nectar make sense, but why are hummingbirds so prickly at feeders, where the food supply is practically endless? In short, because hummingbirds evolved with small portion sizes, not all-you-can-eat buffets. 鈥淔ive or six hundred years ago, you didn鈥檛 have large areas of ornamental flowers, and you certainly didn鈥檛 have hummingbird feeders,鈥 Weidensaul says. 鈥淭hey鈥檝e got millions of years of evolution that tells them, 鈥業 need to fight to protect this food source.鈥欌 To hummingbirds, a nectar feeder is just another flower鈥撯揳 particularly plentiful one, perhaps, but one bound to be depleted before long.

There is no way to completely override a hummingbird鈥檚 protective instincts, but it is possible to encourage greater tolerance among the bejeweled birds. Hummers when there are few flowers and nectar is scarce, so planting native species will help foster a friendlier environment; explore options with 爆料公社鈥檚 native plant database. Weidensaul also notes that they will benefit from more than just the flowers. Since hummingbirds depend on the insects and arthropods found around all sorts of native plants to meet their other nutritional demands, he explains, 鈥渉aving that complexity of structure and diversity of plant species is going to provide a lot more food for the hummingbirds beyond what鈥檚 coming from the feeder.鈥

Another approach is to hang multiple feeders in widely spaced or otherwise hidden locations (for example, around the corner of a house), which prevents conflicts and ensures that every bird has plenty of food. You can also simply hang more feeders in one cluster. 鈥淚f you get a bunch of feeders in one place, and a bunch of hummingbirds coming in to them, at some point, nobody can chase everyone away and they just kind of give up,鈥 Weidensaul says. With enough nectar and a little luck, it may be possible to attract a whole.

爆料公社鈥檚 guide on how to create a hummingbird-friendly yard has plenty more tips to attract鈥攁nd placate鈥攖he feisty fliers. Your actions might not prevent every tail-twitching, feather-flaring spat, but they will help satisfy the tiny birds鈥 enormous appetites and provide them with the food they need to thrive.