As a kid growing up in a small southern Ohio town, on warm summer nights I remember hearing the nasally “peent-peent” flight call of summering common nighthawks as they hunted insects over the street lights. The birds, flashing their distinctive white striped primaries against the dark summer sky, buoyantly flew back and forth eating night-flying insects. This was once a familiar sight and sound across most small towns and cities in Ohio. Even as recently as the 1980’s, common nighthawks were found in 80 of Ohio’s 88 counties during the first Ohio Breeding Bird Atlas (Peterjohn & Rice. 1991). However, since the mid-1990’s common nighthawk populations have declined across much of its range. While still common and widespread, the most recent Breeding Bird Atlas of Ohio reports that within priority survey blocks common nighthawks declined by 67% between the atlas periods of the mid-1980’s to the mid-2000’s. Other numbers suggest that breeding common nighthawks have declined by 2.2% since the 1960’s (Rodewald et al. 2016).
Common Nighthawks belong to a family known as Nightjars, a reference to their loud distinctive calls. Greek mythology suggests that this species would suck milk from goats at night, giving rise to its family common name “goatsuckers.” Worldwide there are 67 species of Nightjars with only seven species in North America. In Ohio, the common nighthawk is one of three species that annually breeds in the state. The Eastern Whip-poor-will breeds throughout much of unglaciated forested Ohio. The much rarer Chuck-will’s-widow breeds in a very localized area of southern Ohio’s Hill Country with Adams County hosting most of Ohio’s breeding population (Rodewald et al 2016).
The Common Nighthawk’s specific name is Chordeiles minor. Chordeiles from the Greek word Chorde, meaning a stringed musical instrument, and deile, meaning afternoon or evening in reference to its late day crepuscular habits. Though they were originally classified as the same genus, the Common Nighthawk’s specific name minor means lesser or smaller, which is a comparison to the larger Eastern whip-poor-will and to the even larger Chuck-will’s widow (Terres 1980).
Common Nighthawks can be described as grayish-brown overall with mottling of various grays, blacks, and browns which provide camouflage while mostly roosting on the ground or lengthwise on a tree branch. Across their North American range, the overall top colors may vary geographically in the dominance of grays and browns. In flight, the nighthawk shows extensive body barring, a white throat line, white central tail feathers, and a distinctive white wing patch in the outer primaries. In the male, the white primaries are broader and the white terminal band in the tail is much more pronounced and distinct than in the female.
Common Nighthawks inhabit a variety of semi-open dry areas, grasslands, pastures and savannas. While they range across these natural habitats, they are most common and often encountered in cities and towns across their breeding range. In these urban areas, they utilize flat gravel-like rooftops as their preferred nesting areas.
The call of the common nighthawk is most often described as a “nasally peent-peent or speak-speak.” This piercing call is given during flight most often at dawn and dusk. The call can be confused with the American Woodcock. However, American Woodcocks return in late February and early March and generally give this call from the ground. Reports of common nighthawks prior to late April are more likely American Woodcocks.
The other sound associated with nighthawks is generally referred to as a “booming sound.” This sound is not a vocalization, but a sound produced by air rushing through the primaries as the male plunges downward towards the ground and abruptly swoops upward as part of its courtship aerial display. While known as “booming” it is more like a rapid “wr-rrrrrrr-oonk.” This sound has also led to another local nickname in some areas of “booming nighthawk.”
While we do not think of nighthawks as game birds today, they were once hunted extensively for sport. “Bull-bats”, as they were called, were hunted by gunners during the nighthawks’ late summer migration as their swift, erratic, irregular flight made them a challenging target. Numerous reports from the late 1800’s note “several hundred birds being shot for sport and table.” Fortunately, this practice was outlawed in the early 1900’s after the National Association of Audubon Societies initiated education efforts to change the hunting laws. In fact, in September-October 1903 issue of Bird-Lore is was noted that one could be prosecuted for shooting “bull-bats” in Greensboro, North Carolina (Bent 1964).
The late summer migration of the common nighthawk is an avian phenomenon that begins to mark the official end of summer and our seasonal transition towards autumn. Nighthawks begin leaving their northern breeding grounds in late July and early August to begin their journey to their wintering grounds in central South America. In Ohio, nighthawk migration produces their peak numbers between August 25th and September 7th. During their peak movement through Ohio, groups of 50-200 may be seen as they fly in loose flocks pursuing insects over open areas, but most reports of them have declined to fewer than 50 individuals. In Ohio, there southward movements abruptly end with only small groups observed after September 12 with a few stragglers occasionally noted through October 15. Prior the mid-1990’s while many observations were of 10-100 birds there were exceptional reports of large movements the produced observations of 1,000-3,5000. One observation from Cincinnati reported an estimated 5,000 birds (Peterjohn 2001). While most agree that numbers during migration have declined on August 24, 2020 observers at The Hawk Ridge Bird Observation in Duluth, Minnesota observed an astounding 27,500 nighthawks as they migrated south off of Lake Superior. Research recently published through The Migratory Connectivity Project visually shows the migration of GPS tagged nighthawks departing from their breeding grounds, their arrival on their wintering grounds in South America, and their return the following spring. This can be viewed at http://migratoryconnectivityproject.org/about/storymaps/. This research is yielding important information that can be applied to the future conservation of this species so that future kids in small towns can watch nighthawks fly over their street lights.
John Watts is a retired Resource Manager, Columbus Metro Parks, and a member of the Ohio Natural Areas and Preserves Association (ONAPA) Board Advisory Committee.
Refences:
Bent, Arthur Cleveland. 1964. Life Histories of North American Cuckoos, Goatsuckers, Hummingbirds and Their Allies, Part One. Dover Publications Inc., New York. 244p + plates.
Cleere, Nigel. 1998. Nightjars-A Guide to the Nightjars, Nighthawks and Their Relatives. Yale University Press, New Haven and London. 317p.
Peterjohn, Bruce G. and Daniel Rice. 1991. The Ohio Breeding Bird Atlas. The Ohio Department of Natural Resources, Division of Natural Areas and Preserves. Columbus, Ohio. 416p.
Peterjohn, Bruce G. 2001. Birds of Ohio. The Wooster Book Company. Wooster, Ohio. 637p.
Rodewald, Paul G. et al. 2016. The Second Atlas of Breeding Birds in Ohio. University Park, PA: Penn State University Press. Pp. 302-305.
Terres, John K. 1980. The Audubon Society Encyclopedia of North American Birds. Alford Knopf. New York.