An early summer camping & birding trip to Okanagan Falls Provincial Park Campground this year proved to be one of my more memorable adventures as my birdwatching interest began to seriously deepen. Within a week, I managed to list almost 60 different species of birds, a huge first in my 5 year gradual seduction into the joys of bird watching & identification. It is also the location of a rare birding event: Nighthawk’s gather just before sunset for approximately 2 weeks during the early part of June, numbering in the several hundreds, to feed on the caddisfly hatch at the Okanagan River. Alerted by Janis the Park Attendant, myself & the people in the campground were offered the privilege of assisting Dr. Mark Brigham of the University of Regina, his wife Anne and assistant Liam from the University of Texas, in a National Geographic funded study of the Common Nighthawk. Mark had placed transmitters and biotags into these birds 2 & 3 years previously, in hopes of determining exactly where these cryptic nocturnal creatures go during their yearly migratory cycle from North America to as far south as the southern tip of Argentina.
Each night, Liam and Mark would begin to set up and man the mist nets across the river about 45 minutes before sunset, there headlamps mysteriously bobbing up and down in the dusk as they bravely waded out into the swiftly flowing river. One slip of the foot, or a misstep with injury had the potential to sweep them downriver into certain death, as a series of deadly weirs control the river a mere 100 meters downstream from the mist nets – a testament to both their courage & their dedication to the study of nature. Anne would document the study with her camera and would also politely inform the people camping near the river as to the reasons behind this strange riverside nocturnal activity, inviting them down to participate in the study, using the opportunity to do valuable outreach and educate the public about the still-very-secret life of the mysterious Common Nighthawk.
THEY ARE COMING
Each night, shortly before sunset, the birders in the campground would gather excitedly along the river, were we would watch the sky above with building excitement & anticipation as the nighthawks left there roosting areas on the flat benches and rocky bluffs above. They began to fly down and gather in a loose group about 200 – 300 feet over the trees along both sides of the river
bank, swiftly increasing in number from tens to several hundred within a few minutes! Clouds of caddisflies, nicknamed “bug balls”, could be seen hovering above every tree and shrub along the river. As the insects are devoured and cleaned up from above the trees, the cloud of madly competing nighthawks begins to condense and lower, compressing into a column of space 15-20 feet thick directly above the water in a scene reminiscent of Alfred Hitchcock’s movie “The Birds”.
Video of the Nighthawk Feeding Frenzy!
Yet these gentle nocturnal creatures are surprisingly graceful as they fly with incredible speed and agility – much like a super-sized version of a swallow – and apparently without any collisions within this highly congested space! Mark shared with us that, “they can still sometimes see the mist nets before total darkness,” where they “swoop down towards the net, see it at the final moment, then stop on a dime, fly straight up & over the net, then drop back down the other side continuing along the surface of the river, – all at break neck speed – like a Jack Russell in an obstacle course”.
The Nighthawk’s bill is quite wide & funnel-shaped, giving it a distinct advantage when feeding on hatched insect populations. In Birds of British Columbia, it is claimed that the nighthawk can consume up to 2600 flying ants, mosquitoes & caddisfly insects in a day! Dr Mark Brigham conducted a study in which he determined that caddisflies are the nighthawks main diet in the Okanagan area, which the Okanagan river has in abundant supply. Elly Knight, Program Manager for the WildResearch Canadian Nightjar Survey, has informed me that in the boreal forest they eat primarily terrestrial insects, including bark boring beetles.
Over the week between 17 & 85 nighthawks were netted each night and checked for transmitters & biotags. None are hurt during the process, though only one or two did complain somewhat, as apparent in the above picture. The biotags contain a thermal sensor to investigate whether or not the birds entered a state of “torpor” a kind of hibernation found only in the Common Poor-will, also a member of the Nightjar family; and a light sensor that could be used for geolocation to determine where they migrate & live. If none were found they were immediately released. Each night several captured birds were carefully taken from there soft-cloth holding bags and feather samples were taken for DNA studies to determine species inter-relationships, and isotope studies to try to determine where they were feeding. This is where the public got a chance to help out and see one of these incredibly beautiful little ” insect hawks ” close up, and to release them after the feather samples were taken.
The first night of the survey, I was given the opportunity to get a closer look while they were taking feather samples, and then enjoy the most incredible experience of releasing one! The Common Nighthawk is a very unique looking bird, with a very large flat head, large eyes suitable for low light conditions, and a wide mouth in proportion to the rest of it’s body. The stunning difference between it’s underneath markings and it’s cryptic, bark-like topside plumage are quite remarkable, and I was moved by the beauty of this fragile little creature.
So I spoke softly to “Lil Opi”, who Liam had nicknamed, while he held her & carefully passed her to me for release, telling her what a beautiful little bird she was, cooing away to her while I gently held her in my hand so she wouldn’t be frightened – doesn’t everyone talk to birds..? – and tried to release her with a gentle upward flick of the open hand. Except she wasn’t having anything of it, and she was quite content to snuggle into the warmth and safety of my hand. After 4 other nighthawks were successfully released, Liam tried giving her a gentle little finger rub beneath the wings & she lifted up her body flapping her wings to fly but snuggled right back in again! Finally, Liam said: “give her back to me David, and I’ll release her. We have 6 more nights to go & we need to go home and get some sleep…” We all had a good laugh at that.
So Anne nicknamed me “The Nighthawk Whisperer”. I was there to help every evening after that. Mark connected me with Paul Preston, the BC coordinator for WildResearch to help do citizen science surveys for the nightjar family, and Ive fallen in love & been hooked on nighthawks ever since! Oh and the results of the transmitters & biotags..? None were found in the captured birds, which means that they likely do not return to the same area yearly to feed. We will have to wait for Dr. Brigham’s research publication for an answer to this mystery.
I felt blessed and was absolutely moved by the connection I experienced in my close encounter with the wonderful little nighthawk. It’s the kind of nature experience that leads one to a much deeper understanding of the privilege, the beauty, and the fragility of life – as expressed by the Creator of all things – and our personal responsibility to protect and preserve it.
I would like to personally thank Dr Mark Brigham, his wife Anne, and Liam, for this most wonderful experience and for the valuable outreach work that they do with regards to bringing field biology, birding, and the love of the natural world to the greater public. Science & nature communicators extraordinaire, our world desperately needs more people like you.
If you are a birder and would like to participate in a citizen science nightjar counting survey, please go to http://wildresearch.ca and find out how to get involved while the survey routes are still available!