Compiled by Jane Tillman for KXAN

What to watch and listen for in May: Night Birds

There’s something mysterious about hearing an unfamiliar sound at night. Is it a bird, an insect, or a frog perhaps? Owls are generally recognizable as owls, but depending on your location it’s possible to hear Common Nighthawks, Chuck-will’s-widows, and much less common Common Poorwills and Lesser Nighthawks. All these are members of the Caprimulgidae family, which includes nightjars and nighthawks. Chuck-will’s-widows and poorwills are nightjars, known for their small bills and large mouths which allow them to catch large insects. They also have large flat heads and rounded wings. They are sit and wait nocturnal predators, watching for flying insects and then flying out from a perch to catch them. What is the meaning of the term nightjar? The word was first used in 1630 to describe the discordant sound of a European nightjar.  Apparently some people regarded a bird singing at night as jarring to the senses.

Unlike nightjars, nighthawks sometimes forage during the day, and hunt insects on the wing. All are masters of camouflage. At rest they blend in with their background of leaf litter, branches, brushy cover and rocky soil.

Common Nighthawks are the most likely encountered species here in Austin as they have adapted to well-lit spaces which attract the flying insects they eat. They can be found flying over baseball fields and parking lots, but also are found in natural settings such as grasslands and open forests. Listen for the “peent” contact call, and look for long, narrow-winged birds with buoyant flight. They gracefully bound through the sky, mouths wide open to funnel in the insects. The males also make a booming sound with their wings after diving toward the ground, which is used to attract mates and to defend their territories. Although they are called nighthawks, they are not hawks, and they don’t typically forage at night. They primarily fly at dawn and dusk, but also on cloudy days and in stormy weather. They might be seen flying low over water or up to 500 feet high.

Common Nighthawk COURTESY: Jeff Osborne

Common Nighthawks don’t build nests. They nest on the open ground, in various unsheltered sites like rocky outcrops, gravel beaches and woodland clearings, but some do choose sites with a little more shelter such as next to grass clumps. In cities they can be found nesting in gravel parking lots and on gravel roofs.

The Common Nighthawk is a long-distant migrant with some coming from southern South America and going all the way to the southern half of Canada. They are summer residents over most of the U.S. Unfortunately they are a declining species, perhaps due to declining insect populations.

Over the past decade or so the Lesser Nighthawk, which typically has been a south and west Texas species, has been recorded more frequently around Austin during the summer months. It’s not noticeably smaller than the Common, but it has more rounded wingtips, an odd low, garbled trill rather than the Common’s “peent,” and does not do the diving display of the male Common Nighthawk.

Lesser Nighthawk COURTESY: Arman Moreno

Chuck-will’s-widows are summer nightjars of the southeastern states including parts of Texas. They spend the winter in Central America and northern South America. Austin’s Chucks arrived in mid-April and will be here until mid-August.

Chuck-will’s-widow COURTESY: Vincent O’Brien

Chucks are an enigmatic species, cryptically colored and rarely seen. However if you live close to mixed woods you may hear them. Commons Ford Ranch Metro Park is a good place to listen for them singing “CHIP wido WIDO” over and over. They forage mostly at dusk and dawn, but may feed all night if it’s moonlit. Their close relative, the Eastern Whip-poor-will, only passes through Texas to breeding grounds in the eastern and northeastern states. Whips sound somewhat similar, but you have to be really lucky to hear one during the narrow migration window of mid-March to mid-April.

Chucks don’t build nests, instead laying their eggs in the leaf litter or on bare ground where they blend right in. Their diet of flying insects includes moths, dragonflies and beetles. There are also records of them eating frogs and small birds such as warblers.

Common Poorwills are small members of the nightjar family. They are on the eastern edge of their breeding range here in Austin, and the best place to hear them is at Reimers Ranch County Park. They occur in a variety of habitats from prairies to dry and rocky hillsides usually between 1,000 and 7,000 foot elevation. In part of their U.S. range they are year-round, but in most of their range they are summer residents, spending the winter in Mexico. The Hopi Indians called them the “sleeping ones” as Poorwills go into a state of torpor if conditions are so cold that insect prey is difficult to find. Scientists have found that Poorwills can lower their body temperature to 41 degrees F and reduce oxygen consumption by 90% until conditions improve. Common Poorwills sing their name “poor will” on spring and summer nights.

Common Poorwill COURTESY: Arman Moreno

When to Go Birding during Migration?

Migration is still underway in May. Local breeders are on territory so the migrants passing through Austin now are on their way to northern regions.

If you want to know exactly how many birds might be in the air, night by night, during migration, check BirdCast, a collaborative effort to understand and predict bird movements based on weather radar surveillance. You can even check to see whether birds will be migrating over Austin in low, medium or high densities with the local migration alert feature. Keep in mind that even though a large number of birds might be moving through, they may not stick around the next day. Birds are in a hurry to get to their breeding grounds to get the best territories.