Where has the Whip-poor-will gone?

June 27th, 2015 11:19 pm

Although its numbers have declined, the whip-poor-will can still be seen, and heard in Pennsylvania.

A spattering of stars peeked through the partly cloudy night sky. Along a desolate country road and under the diffuse glow of an unseen moon, the ping-ping-ping of the door alarm sounded as I exited the state truck. The date, time, location, and moon phase for the early June survey was chosen well in advance to offer the best opportunity of hearing what I was desperately hoping to hear. I felt hopeful – but not what you would call optimistic – when my watch indicated it was time to proceed.

The song of the elusive bird was something I had not heard since childhood. This nighttime serenade was relegated to serving as a musical score for increasingly distant memories of lazy summer evenings sitting on an uncle’s back porch near a patch of woods, with relatives long since passed, listening to a small bird hauntingly repeat its name over, and over again.

One minute elapsed. The road behind the truck wrapped around the base of Hickory Nut Hill, just outside the little village of Waller, in northern Columbia County. From that direction, not too far away, an unmistakable rhythmic, plaintive call pierced the silence and filled me with nostalgia: Whip-poor will, whip-poor-will, whip-poor-will. A smile crossed my face. After only a few repetitions, the calling abruptly stopped and would not resume.

Only other nighttime denizens greeted me at each successive listening location. The last of the spring peepers peeped, American toads trilled, a great horned owl hooted. The air temperature steadily dropped as the sky transitioned to mostly cloudy, then completely overcast. Conditions for optimal whip-poor-will calling gradually worsened and, by the time the route was completed just before midnight, a drizzling rain fell. “Did you hear any?” my wife later asked as I wearily crawled into bed. “One,” I replied and drifted off to sleep. She had no idea how much it meant to me to hear that single bird.

Whip-poor-wills

The eastern whip-poor-will belongs to a group of nocturnal insect-eating birds known as “nightjars” because of their nocturnal habits and the jarring aspect of their vocalizations. Other nightjars found in Pennsylvania are the common nighthawk and the rarely documented chuck-will’s-widow.

Nightjars also are called “goatsuckers,” stemming from a false notion that the birds would fly into barns at night and use their expansive maws to suckle milk from goats and other livestock. In folklore, the call of the whip-poor-will was considered an omen of death and substantial calling of the birds indicated an impending storm. The Mohegan tribe of Native Americans held the belief that makiwasug (magic little people) traveled through the forest at night in the shape of whip-poor-wills.

The squat and diminutive adult bird weighs around 2 ounces with a wingspan of 19 inches. A whip-poor-will has a gaping mouth and sports two vertical rows of bristles flared toward the front of the bill to funnel insect prey captured in flight. Its plumage is a mix of camouflaging browns and grays.

Whip-poor-wills perch on branches or sit on the ground where they fly up to catch beetles, mosquitoes, gnats, and a variety of moths. The birds are most active on moonlit nights when moths and other nocturnal insects are backlit against the bright night sky.

The whip-poor-will is named for the male’s repeated springtime nocturnal calling. The whip is sharp, the poor falls away, and the will is the highest note. The amorous bachelors call mainly at dusk and dawn to attract females. In Pennsylvania, whip-poor-wills start calling in late April or early May, when migrating males arrive from the southeastern United States, Mexico, and Central America. The calling continues through June and fades away in July.

Eastern whip-poor-wills require large tracts of forests with sparse understory and inhabit deciduous and mixed deciduous-coniferous stands with scattered open areas for foraging. They prefer young forests with clearings and are also found in the scrub oak barrens habitat of the Poconos.

In recent years, conservationists and the general public have come to share a general sense that populations of nightjars have been declining. However, there was no empirical data to help describe the changes or to help plot a strategy to reverse population losses.

In 2007, the Center for Conservation Biology – a cooperative of the College of William and Mary and Virginia Commonwealth University - formed the National Nightjar Survey to collect current nightjar distribution and population data. The Pennsylvania Game Commission is a partner in this effort.

Volunteers conduct standardized roadside counts on scheduled moonlit nights, by driving and stopping at 10 points along a predetermined route. At each point, observers count nightjars seen or heard during a six-minute period. Gathering this information over time will point to changes in nightjar distribution and population size while experts simultaneously analyze changes in habitat composition.

A dramatic decline of the whip-poor-wills in Pennsylvania can be seen when comparing numbers of these birds noted during the first Pennsylvania Breeding Bird Atlas survey conducted from 1983 to 1989, and the second survey conducted from 2004 to 2009. Nightjars, as a group, were found to be experiencing the steepest decline of all insectivorous birds and overall whip-poor-will detection declined 42 percent.

The bird nearly disappeared from previously occupied parts of western Pennsylvania and had drastic losses in the northeast portions of the Ridge and Valley Province. This drop prompted the Ornithological Technical Committee of the Pennsylvania Biological Survey to list the eastern Whip-poor-will as “vulnerable” in Pennsylvania.

The whip-poor-will’s decline is a complex issue that likely stems from a combination of several factors. A decline in aerial insects, especially moths, could be contributing to the decline whip-poor-wills and other insect-eating birds, including the common nighthawk. Dependence on aerial insects is something all nightjars have in common. Some scientists believe agricultural pesticides might be playing a role, as well.

Habitat loss and composition changes might also be key factors in the decline. Whip-poor-wills are an edge species that needs a mix of young-forest areas for nesting and open areas for foraging. Locations meeting these specific habitat requirements have dwindled in the northeastern United States and Canada through a combination of development and forest maturation, resulting in fewer prime spots for whip-poor-wills.

The problem also could originate in the whip-poor-will’s wintering grounds, which stretch from the Gulf states to Honduras. Little is known of changing habitat conditions and human encroachment in these areas.

On state game lands, the Game Commission uses land-management practices such as timber-stand improvement and prescribed-fire operations that could benefit whip-poor-wills. Efforts to create and enhance young-forest habitat for species such as the golden-winged warbler and American woodcock, could help the eastern whip-poor-will, as well.

A few days after that nightjar survey when chores at the barn were completed and the sun slipped over the horizon, a bird began calling as I walked back to the house.

My wife and I stood on the front porch. “Listen,” I said. For a few moments, only silence. Then, from atop a nearby ridge, we heard a lone nightjar calling out its name.

“I am here” it proclaimed, over and over again.


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