It was just before dusk when I ventured into the woods. The sky was veiled in clouds save for a few small breaks in the overcast which permitted the sun’s final rays to cast their strained light on the tallest pines. I slowly plodded along the dirt road, straddling the potholes and skirting the muddier sections. On I went, past sleepy homesteads and over the crude metal bridge over the muddy waters of Martin Stream, the threshold of their domain. I had visited this stretch of woodland many times before, by day to better know their lands and by night to bear testament to their moonlit incantations. Even in the settling dark this isolated forest felt familiar. I parked my car and watched the mosquitoes bounce against my windows in the fading light of day. The hour was close at hand.
I left the protection of my car and was immediately set upon by the biting-insect swarm that had congregated. I stood at the forest’s edge swatting and straining my ears. Off in the distance, a Common Nighthawk gave a series of nasally “peent” calls. Among the calls, a rushing “vrrroooom!” rings out. This was a male nighthawk performing a courtship display called a “boom”. The sound is non-vocal and comes from the rushing of the wind through a diving nighthawk’s flight feathers. It is used by male nighthawks to court potential mates and to defend its territory from intruders. The day slips further towards night as I focus skyward for awhile, hoping to catch a glance of the aerial performance against the clouds.
Suddenly my attention is drawn back down to the forest. A song rings out from the dim forest floor just across the road - “whip-poor-will, whip-poor-will, whip-poor-will!”. This is the onomatopoeic song of the Eastern Whip-poor-will and precisely why I’ve come to this place time after time. I stand and listen to the nocturne and am as enchanted as I was the very first time I heard it. The bird stops singing, changes position, and resumes. He is claiming this stretch of forest as his own and, through his vigorous singing, demonstrating his worthiness as a mate to any females in earshot. He stops again, descends to the roadway, and resumes his singing, affording me the rare visual observation. I can just make out his robin-sized dark form and the bit of white in his plumage. After several minutes of singing, he takes flight again just as I turn on my headlamp. His eyes are like floating embers drifting through the night air in the light cast by my lamp. I watch as he circles back towards the patch of woods where his song began and it dawns on me that I’ve been encircled. This observation is different from those of the past.
The significance of this encirclement has everything to do with Eastern Whip-poor-will breeding behavior. Whip-poor-wills are nightjars - a group of secretive and well-camouflaged birds that are active primarily at night. The nest on the forest floor, depending upon their superbly cryptic plumage to hide them from predators. Male whip-poor-wills sing at dusk, dawn, and all throughout moonlit nights to define their nesting territories. They patrol the territory boundaries and sing from the ground, tree limbs, stumps, and sometimes houses and other man-made structures. While I have heard whip-poor-wills singing and changing posts many times before, this was the first time I had found myself within a breeding territory. An hour into my observation, something even more interesting happened. While the first whip-poor-will sang from a more distant perch, another bird called from the woods just a few feet across the road. This bird was not singing the onomatopoeic song, however. It was giving a short “quirt” call. These rarely heard whip-poor-will calls are typically used by pair members to stay in contact with one another during the breeding season. At this, the distant singing came to an abrupt halt. Using my headlamp, I watched as the male flew in from its singing post and descended out of sight near the source of the calling and right near the place it had originally started singing. I had potentially found a breeding pair of whip-poor-wills. This was a rare event and one that is becoming increasingly rarer as whip-poor-wills suffer declines throughout eastern North America.
As fascinated as I was by this observation, I knew I shouldn’t stick around if I wanted to avoid disrupting these birds. I climbed back into my car and drove out of the woods and back towards home to strategize future observations and ways of confirming my suspicions while causing as little agitation as I could manage. While limiting disturbance and preventing harm is always a priority in my observations, this was a particularly sensitive case. Recently concluded research efforts have revealed that 1 in 4 North American birds has vanished from the continent in just the last few decades. Aerial insectivores, a group of birds to which nightjars belong, have been especially impacted. Anecdotal reports from throughout Maine indicate Eastern Whip-poor-wills and Common Nighthawks have suffered significant declines here in our state, leading to their listing as Species of Greatest Conservation Need. The impacts of climate change and habitat destruction threaten to further imperil Maine’s nightjars. I’ve devoted the last several years of my life to studying nightjars and started a state-wide citizen science monitoring effort when I learned of their declines. While I was highly interested in this unique opportunity to observe the secretive whip-poor-will during the breeding season, their well-being was paramount.
An Ovenbird - a warbler species frequently heard singing their loud refrain of "teacher! teacher! teacher!" by day and performing their garbled flight songs by night.
Rather than return the next day, I gave the birds a few days without any disruption before I returned. Instead of coming by night when the birds were active, I came at midday when the birds would be asleep. My chances of finding a motionless and well-hidden bird were slim, I knew, but I was determined to try my luck. I scanned woods along the sandy roadside fruitlessly while blackflies and mosquitoes buzzed in my ear. Black-throated Blue Warblers, Ovenbirds, and other warblers sang and flitted through the trees. Off in the distance, a Veery sang it’s slurry, descending song from beside a trickling pond outlet. Lady’s-slippers, starflowers, and pipsissewa popped through the duff of pine needles and oak leaves. No whip-poor-wills in sight. I began to think about leaving. Walking gingerly back along the wood’s edge, an unusual noise broke through the sweet midday chorus of songbirds - “aug-aug-aug-aug-aug”. This was another whip-poor-will vocalization I had only rarely heard before and had never heard by day. This throaty call is used to challenge intruders. I turned slowly towards the source of noise and spotted them. Perched atop of hunched over gray birch was a squinting whip-poor-will. On the ground beside it was a second whip-poor-will. Before I could even think to reach for my camera, the birds flew together a dozen or so feet further into the woods. I was clearly detected. I retreated to my car and spent half an hour reading and taking notes. Eastern Whip-poor-will pairs roost together only during the breeding period immediately before nesting so while this pair may not have nested yet, they very well may soon. I quietly recrossed the road with my camera at the ready. I climbed a small hillock and lay with just my head and hands above the ridge. I panned the forest floor and to my surprise and delight discovered that the birds had returned. Perched atop a lichen-encrusted stump was the male. I held my breath, snapped a few photographs, and again retreated. I drove home overjoyed. Despite years of fascination with this bird species, I had never seen one clearly with my own eyes until today.
Given my belief that the pair was in the formative stages of their nesting period, I made the decision not to return until nesting would be well-underway. Although I thought about them everyday and wondered about their progress, I did not return for nearly two weeks. Fortunately, I was occupied with conducting nightjar and alpine bird surveys all across the state. While I wasn’t getting to observe whip-poor-wills directly, I was spending many nights up listening for their songs. At last, I felt enough time had passed and that I could safely return to try and confirm their breeding success. I returned to find the woods, again, dappled with sunlight. Red-eyed Vireos sang ceaselessly from within the canopy. I was prepared for another long stint of scanning and again reflected that my efforts might be for naught. Again, I was surprised. After only a few minutes of scanning, I saw her. She flushed upwards and settled a few feet distant back onto the ground. She fluttered and outstretched her wings, feigning injury to divert my attention. The source of her agitation was plain. Just a few from me were two of the most beautiful things I had ever seen. Two white eggs spotted and smudged with grays and warm brown. They had a fittingly lunar quality and looking at their shell felt very much like gazing at the surface of the moon. My attention returned to the female who had not ceased in her spirited defence. I snapped a few few photographs of her and her eggs. Even though it had only been minutes, it was time to go and I would not return again this year.
Looking at those eggs was very affecting. They held so much hope and promise in a time when it would be easy to despair. Eastern Whip-poor-will were once so common that their singing was synonymous with summer nights in eastern North America. Their songs were the soundtrack to evening fishing trips, the lullabies of woodland campers, and relentless yet reliable hymnals of day passing into night. While the whip-poor-will’s song can still be heard in pockets of the state, it has become all too rare. The driver behind this decline is elusive, but fits into the broader pattern of declining bird numbers throughout North America. Habitat destruction, declining insect populations, forest maturation, predation from free-ranging pets, collisions with vehicles (whip-poor-wills often sing and forage from open places like roads), and many other factors have been suggested as plausible causes for declines. It is highly likely that a combination of these and potentially other drivers are leading to the decline of the whip-poor-wills. Climate change poses a serious threat to whip-poor-wills and is likely to make large swaths of their summer range (as much as 80%) unusable for breeding. Under these scenarios, whip-poor-wills will have to travel further from their wintering grounds to reach suitable nesting grounds. On their nesting grounds, nightjars will have to contend with increased rainfall (which can flood nests) and heat waves (which can put vulnerable young in jeopardy). On their winter grounds, they likely face many of the same stressors and threats. Maine is somewhat uniquely positioned among New England states in that more areas of the state are likely to become suitable due to climate change. While whip-poor-wills are known to readily move into new suitable nesting site, how this will unfold during this tumultuous and rapidly changing period remains to be seen.
Eastern Whip-poor-will range changes under climate change projections as predicted by researchers at the National Audubon Society. For more information, click here.
My experience this summer demonstrates that there is still room for hope so long as we can be proactive. New England and eastern Canada may become refuges for these and other birds pushing north to weather the impacts of climate change. Monitoring and research efforts focused on nightjars are taking places throughout the northeast. Whip-poor-wills have been recognized as a species of conservation concern and the first ever management efforts focused on creating breeding habitat are underway. The migration and wintering habits of these birds are being studied for the first time. In just a few short weeks, the Maine Natural History Observatory is hosting a roundtable of northeastern nightjar monitoring efforts to discuss collaboration between our programs and areas for future research. This will be an unprecedented gathering of representatives from several states and Canadian provinces.
There is much that we, as individuals, can do to help whip-poor-wills and other birds weather this unprecedented period of change. The Maine Nightjar Monitoring Project (and other regional efforts to monitor nightjars) depends upon volunteers to adopt and survey specially-designed routes each year. Collecting data from these routes help us to better understand the status and distribution of our nightjars. Several routes in Maine have yet to be adopted. We can also make steps to safeguard whip-poor-wills and many other bird species by not allowing our pets to roam free outdoors, especially during the breeding season. Supporting nonprofit organizations conducting research and involved in bird conservation by volunteering your time and/or making charitable contributions helps to ensure that vital work can be sustained in this most critical hour.
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