Hummingbirds are known for their beautiful, iridescent plumage and their ability to hover and fly backwards. They are also fiercely territorial, especially when it comes to food sources like backyard feeders. Chasing and aggressive behavior is common among hummingbirds competing for limited resources.
Territorial Behavior
Hummingbirds are highly territorial and will aggressively defend their food sources and nesting areas. A hummingbird feeder provides a concentrated source of food that is worth protecting. When multiple hummingbirds attempt to feed at the same feeder, chasing and squabbling often ensues as each bird tries to claim the feeder as its own territory.
Male hummingbirds are especially territorial. During breeding season, male hummingbirds will stake out flower beds, feeders, and other nectar sources to attract females and proclaim dominance. They will chase away any intruders, even chasing much larger birds like crows out of their territory.
Establishing Dominance
Chasing is one way hummingbirds establish dominance and claim prime feeding areas. The dominant bird will perch nearby and dive-bomb any intruding hummingbirds that attempt to approach the feeder. This chasing behavior will continue until the intruder leaves the area. The dominant bird will also make display flights and vocalizations to reinforce its claim over the territory.
Younger, subordinate birds are the most frequent targets of these attacks. Juvenile hummingbirds may be chased dozens of times a day until they find an opening to access the feeder or give up and search for food elsewhere. However, adult hummingbirds will also chase each other on occasion to assert their status.
Competition for Resources
Access to food sources is vital for hummingbirds, as their fast metabolism requires frequent energy intake. Hummingbirds need to consume nectar every 10-15 minutes to avoid starvation. This can lead to fierce competition when multiple hummingbirds are drawn to a backyard feeder.
The availability of flowers, tree sap, and other natural food sources can impact hummingbird behavior at feeders. During times of scarcity such as migration or winter, chasing may escalate as hummingbirds become desperate to maintain access to a stable food supply.
Feeders should be spaced widely apart or multiple feeders should be used to reduce squabbling over limited food. Faster feeding hummingbird feeders may also help minimize chasing by allowing quick access for multiple birds.
Breeding Behavior
In addition to food, male hummingbirds may chase others away from nesting sites or female hummingbirds. Aggressive displays are used to proclaim dominance and advertise to potential mates.
Chasing serves to warn rival males away, indicating that the area is claimed for breeding purposes. Females may also be chased but usually not to the same aggressive extent as males. Some chasing of females may be part of courtship rituals.
Protecting Eggs and Chicks
Once hummingbirds have nested and laid eggs, they become even more defensive against intruders. Nesting females will dive-bomb any approaching hummingbirds, as well as larger animals. This helps ensure their eggs and chicks are protected.
Areas around the nest are fiercely guarded, and the mother hummingbird will continue chasing others away throughout nesting and rearing of the chicks. As the chicks near fledging and leave the nest, this behavior diminishes.
Misdirected Aggression
In some cases, chasing may be a result of misdirected aggression. Hummingbirds may instinctively attack anything that moves near their territory, including other hummingbirds, animals, and people.
If a hummingbird appears to repeatedly attack a particular bird at the exclusion of others, it may be due to misdirected aggression precipitated by an earlier territorial encounter. This behavior usually resolves within a day or two.
Preventing Chasing at Feeders
While chasing is a natural hummingbird behavior, there are some steps that can be taken to minimize aggression at feeders:
- Provide multiple feeders spread widely apart to distribute birds over a larger area
- Use feeder styles that allow multiple feeding ports or feeding opportunities
- Locate feeders in open areas away from dense foliage or nesting sites
- Avoid overly coloring or decorating feeders, as these may attract birds and increase territorial behavior
- Clean feeders regularly to ensure ample nectar availability
- Use feeders with perches so dominant birds can stake out a preferred spot
In most cases, chasing is brief and does not result in any real harm to hummingbirds. But by making a few adjustments, homeowners can create a more peaceful feeding experience that allows multiple hummingbirds to comfortably access nectar.
Conclusion
Chasing and aggressive behavior among hummingbirds occurs as a result of territoriality, breeding activities, and competition for limited nectar resources, especially at backyard feeders. Dominant birds will dive-bomb intruders to claim prime feeding areas and advertise themselves to potential mates.
While chasing may seem disruptive to human observers, it is simply a natural behavior related to survival and reproduction. Providing adequate feeder space, nectar, and perches can help reduce squabbles so hummingbirds can peacefully feed.
References
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