Wednesday 11 September 2019

Hunting for flying insects

Yesterday, I was working in South Ronaldsay, not far from some bog pools which hold several species of Odonata. As it was a sunny day with only a light breeze, I reckoned that it might be worth taking along camera and bins, just in case.

With the job done and it being lunchtime, I parked near the pools and wandered along the track which runs between them. There were loads of bumblebees buzzing about, several butterflies (a Painted Lady and a Red Admiral) and many, many crane flies, but no dragonflies (this is a Black Darter site) or damselflies (Blue-tailed or Emerald) to be seen.

Painstakingly, I scanned the waterside vegetation with my binoculars, willing an odonate shape to come into focus. I stared at the wider landscape hoping to catch the sparkle of light reflecting from a delicate wing. I searched in the lee of a small willow plantation, where the air was still and warm, and there were plenty of insects here, just not a dragon or a damsel.

Forlornly, I headed back towards the van, pondering whether this would be a year when I wouldn't be able to find Black Darters at these pools, when a distant movement caught my eye. Across an enclosure, sat on the wire of the far fence, was a bird. As the Autumn migration is now well underway, my initial thought was that, to the naked eye, it was quite large and pale for a warbler. Looking through my bins, I realised my error, as the bird was a flycatcher of some sort. Trying not to wonder what it had just eaten, I fumbled for my camera but, in that split second of inattention, the bird disappeared. Gah!

Flycatchers do not breed in Orkney, so this was a bird on passage from wherever it raised a family this Summer, en route to its wintering grounds in West Africa.

I went back to staring at the wider landscape again, in the hope of catching another glimpse. I was quite sure that it wasn't a Spotted Flycatcher, as there were white stripes on its wings, but my knowledge of flycatchers wasn't up to being any more positive than that. After spending some time ambling to and fro along the track, I caught a brief view of the bird behind some willows, as it took to the air to catch an insect, and then plunged back behind the bushes. This was why I had lost sight of it. The initial view had been across low vegetation, mainly heather, but the remainder of the fence line was masked by a stand of willow, and this was where the bird was hunting, making forays into the air for prey and returning to its hidden perch on the wire fence.

Continued staring brought the occasional flurry of wings (and presumably the certain death of a small invertebrate), but did little to help me identify the bird. Eventually, I decided enough was enough, and I opted to skirt around the southern flank of the enclosure by climbing over a gate and quietly creeping along the edge of the willows until I could see back up the western fence line.

There wasn't a bird there.

There were two. Yay!

Both were flycatchers and both were busy living up to their name, feeding hungrily on their journey south and not particularly bothered about my presence. Now I could see their wing markings properly, I was still no wiser as to the species, but I was able to take photos for use later.

Recourse to several ID guides brought me to the conclusion that these are female Pied Flycatchers. This pair instantly doubled the number of Pieds I have ever seen anywhere, and it will be well over ten years since my last sighting.

But... there's still that niggling doubt of just what they were eating before I spotted them. 


Mark said...

Hope they hadn't been eating Damsels!!!

Imperfect and Tense said...

It's a concern!