Surveying Nightjars

nightjar smallYesterday gifted as glorious a summer evening as we have seen of late, and as the sun was beginning to dip behind Exeter, I decided to undertake a second Nightjar survey of the old site of Dalditch Camp, the training headquarters of the Royal Marines during WWII.  Once a bustling community with a population bigger than Budleigh Salterton, nature has now reclaimed the site which has become a significant biodiversity haven. East Budleigh Common has a wild secluded feel. Despite a noticeable low level background hum of traffic, it is easy to imagine oneself to be somewhere far remoter and more exotic than countryside within a few minutes of Exmouth.

Having returned to the Commons in April after over-wintering in Africa, the Nightjars are now in full voice, and East Budleigh Common is one of the best places to hear their enthralling evening call. At the time the Pebblebed Heaths were designated as a Special Area of Conservation in 1998, 83 breeding pairs of this species were known from the Heaths representing about 2.4% of the known UK breeding population. Since that time their population has been largely stable. National surveys have been the primary means of monitoring their fortunes, with these carried out in 1974, 1981, 1992, 2004 and 2010. To supplement this data we also undertake annual surveys on Common land where we know they have a significant presence.

Upon closing the door of the car the nearby presence of Nightjars was clear from their distant churring behind a beech woodland, and with only an hour of light left I quickly headed into the scrub-dominated interior of the Common along a narrow track. My mission was to pinpoint the territories closest to me.  It is the unmistakeable territorial call of the male that is most noticeable, and its extraordinary vibrating sound is one of the quintessential sounds of summer. However, trying to accurately track the caller can be problematic as the Nightjar’s voice carries over hundreds of metres and is of broken duration. When a number of males call simultaneously it can be difficult to beam in on a single source, especially in fading light and within a labyrinthine landscape of heath and woodland scrub mosaic.

Following the track across the Common towards the nearest churring, every clearing had an abundance of rabbits, their white tails still conspicuous in the half light as they scuttled off into the brambles beneath the birch. Rising and falling with the terrain, the smell of the land constantly changed with topography. Now the deep earthy scent of fresh bracken in the hollows; now the warm aromatic aura of dried bent grass on the rises.  The intermittent silhouettes of giant Scot’s pines loomed above, their pagoda branching stark and black against the deepening blue of the sky. During pauses in the Nightjar chorus line, the sounds of other wildlife drifted across the landscape: the hooting of a tawny owl from the woodland copse behind me; the abrasive rasping cry of a startled pheasant from an adjacent conifer plantation; the alarm call of a blackbird, startled by my sudden appearance.  

Upon entering a clearing of sparse heath, the fluorescence of the heather flowers dulled by the last gasp of dusk, I heard a plaintive yap. Not the distinctive territorial call of the Nightjar, but a gentler call, and a male ascended from the ground within metres of my feet, and with lazy wings flapped around me rising and falling close to the ground. Its white markings were unmistakeable, despite the encroaching dark obscuring its form. It alighted fleetingly on the bough of a dead ivy-heavy pine, then descended again to its resting place on the ground. Thrilled to have seen my quarry in such close proximity, and with one more sighting marked I hurried back to the car, the track now harder to follow, the birches looming on either side.

Before driving off, the new location safely marked onto a map, I stood by the car for a few minutes and breathed in the night air. All of a sudden it seemed that all the Nightjars of the area were calling in unison. I had never heard so many before. More than a churring; a beautiful mass chorus haunting the night. And even though the amber glow of Exmouth was now clear against the night sky, the unmistakeable sign of human power, for a moment at least, the calling, the overwhelming presence of this spectacular species hinted at the even greater strength of nature.     

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