The bird that is known for making a sound similar to a machine gun is called the Common Nighthawk. This medium-sized bird has pointed wings, short legs, and a large head. Its plumage is mottled brown, gray, and white, providing excellent camouflage as the nighthawk rests on the ground during daytime. The most distinctive feature of the Common Nighthawk is its wide, gaping mouth that it uses to catch insects on the wing. But it is the male’s mating call that gives the nighthawk its machine gun nickname.
The Nighthawk’s Unique Call
During breeding season, the male Common Nighthawk performs elaborate aerial displays to court females. An important part of the courtship ritual is the male’s unique vocalization. While diving through the air, the male makes a loud, aggressive booming sound that is best described as resembling the “burst of a machine gun.”
This jarring, mechanical call is created by air rushing through the male’s primary wing feathers during his steep dives. The changing airflow causes the wingtips to vibrate, creating the loud, reverberating booms. These booms can be heard up to a mile away on quiet nights.
The booming cries not only help attract female nighthawks, they also communicate the male’s fitness. Females seem to prefer males who can produce the loudest bursts, which indicates physical health and vitality.
Reasons for the Unique Call
There are a few theories as to why the Common Nighthawk evolved to use such an unusual mating call compared to other birds:
- The jarring boom carries well over long distances, allowing the male to advertise his presence to females across a wide area.
- It cuts through ambient noise, making it easy for females to pick out even with other nighthawks displaying at the same time.
- It may startle potential predators, possibly helping to keep the displaying male safe.
- It conveys the male’s vitality by the call’s strength and duration.
In addition, some experts suggest the mechanical, jolting sound actually mimics the wingbeats of large, swooping owls. If true, the nighthawks may be tapping into an innate fear response in predators, essentially using “bird scaring” sounds to their benefit.
When and Where to Hear the Booming Call
The best time to hear the Common Nighthawk’s machine gun-like call is during the breeding season, which occurs between spring and early fall depending on latitude. In North America, breeding typically happens between May and September.
The booming sounds are produced only by males during courtship displays or territorial fights. Females may make a simple “peent” call when approaching a roosting site, but in general nighthawks are mostly silent outside of male breeding displays.
Nighthawks are most active around dusk and dawn, so their frenzied booming is often most intense just before night falls as males compete to attract mates. Primitive clumps of nests can even form on bare ground where several females cluster, drawn in by boisterous males.
Good locations to listen for nighthawks include large open fields, grasslands, deserts, gravel beaches and rooftops in urban areas. The calls carry well in open habitats away from dense tree cover.
Variations Between Species
There are several nighthawk species worldwide that exhibit similar booming courtship calls, though the Common Nighthawk’s is often considered the most intense and machine gun-like:
- Common Nighthawk – Most aggressive. Widespread across North America.
- Antillean Nighthawk – Caribbean islands. Lower, less raspy call.
- Lesser Nighthawk – Southwestern North America. Slightly higher pitch.
- Chuck-will’s-widow – Southeastern North America. Lower, hoarser two-part call.
While the calls differ, they all serve the same purpose – loudly advertising the male’s location and fitness in hopes of attracting a mate. The Common Nighthawk is simply the champion when it comes to volume and intensity.
Other Interesting Traits
Beyond the riveting mating call, the Common Nighthawk exhibits some other fascinating traits and behaviors:
- Migrates long distances, wintering as far south as Argentina.
- Cryptic coloring camouflages the nighthawk against the ground where it nests.
- Hunts on the wing by night, preying on moths, beetles and other flying insects.
- Mouth extends far back behind the eyes giving it a huge gape.
- Long pointed wings allow for acrobatic aerial displays.
- Nest is simply a bare scrape on gravel, requiring little maintenance.
- Performs a late autumn migration unlike many other North American birds.
Population Declines
Despite its adaptability, the Common Nighthawk has experienced significant population declines since the 1960s. The reasons are not fully understood, but likely include:
- Reduced insect prey from pesticide use
- Habitat loss as grasslands are converted to agriculture
- Declining nest success rates potentially tied to predation
- Collision hazards from buildings and towers during migration
More research is needed to better understand causes of the decline and how to reverse it. Some steps to help nighthawks recover include:
- Preserving large tracts of undisturbed grasslands and shrublands
- Allowing natural forest fires to maintain open habitats
- Minimizing pesticide use where possible
- Enforcing building height restrictions and tower designs to reduce collisions
Appreciating the Common Nighthawk
The Common Nighthawk may be declining, but it remains widespread across North America and is still a remarkable bird. Listening to its bizarre booming calls on a quiet summer evening is an unforgettable experience. This strange vocalization allows the nighthawk to perfectly fill its niche – advertising itself loudly and clearly to mates and competitors.
The next time you hear what sounds like a sputtering engine off in the distance on a warm night, take a moment to appreciate the industrious courtship ritual of the noisy Common Nighthawk!
Conclusion
The unique mating call of the Common Nighthawk has earned it the distinctive nickname of the “bird that sounds like a machine gun.” This medium-sized, cryptically colored bird produces loud, aggressive booming sounds with its wings during courtship dives and territorial displays. The booming carries for long distances, allowing males to advertise themselves widely to potential mates. The Common Nighthawk is just one of several similar species found worldwide that use this conspicuous booming behavior. While its population has declined significantly in recent decades, focused conservation efforts may help stabilize and restore numbers of this fascinating aerial insectivore known for its commanding boom.