It was the last day of 2018 and I stood overlooking a Welsh valley. From the river running along its floor, closely followed by a road, to its rounded tops towering above, it was a patchwork of colours that on this rather grey, overcast day, were rather muted. There were dark greens and browns of woodlands, lighter greens of grassy fields dotted with white sheep, and large swathes of reddish brown bracken. I stood in a large open paddock with closely cropped grass, and three old gnarly trees. Their bare, twisted branches join beautiful lumpy and bumpy trunks. On one of these trees, a short distance up its trunk, was positioned a triangular shaped owl box.
We had been asked to come and check this box by a local bird ringer with whom we have done quite a bit of ringing in the local area over the last few years. He monitors a number of barn owl boxes in the area, and earlier in the year when checking this box for nesting had managed to read a ring on the female occupying it. Not so unusual. But the ring number he had read was one put on a young owl in Northumberland. Barn owls are sedentary and generally do not move too far from where they are born, with the majority staying within 10km of a nest. So while long distance movements are certainly not unheard of, in most cases birds do not travel far. Could this bird really have come from the other side of the country? Or could it be an unfortunate case of a misread ring?
With our experience of catching adult owls at boxes, we were asked if we could attend the site with the ringer to try and catch the bird again, to double check the ring number. Being outside of the breeding season there was no guarantee any owl would be in the box, let alone the female we were hoping for.
We approached quietly down the slope, making as little sound as possible so as to not flush any potential bird out prematurely. However on placing the net over the hole and giving the box a little tap, nothing happened. With the net remaining in place we set the ladder against the trunk and Lee climbed up to check. He opened the hatch carefully. Just because no owl had flown out, did not mean there was no owl in the box, with many known to sit tight. Carefully he reached in to find an owl! But not just one owl. There was a second bird in the box! Fortunately Lee kept his wits about him and the entrance was closed enough to prevent the second bird escaping. He brought the first bird down. It is unringed. We go through the procedure of ringing, aging and sexing the bird. It is pale, with very few spots on its flank and limited barring on the wing, and is recorded as an adult male.
Lee then returned to the box to get the second bird. With baited breath we waited at the bottom of the ladder. Is this second bird also unringed? Or if it is ringed is it the same number recorded before, and therefore potentially a bird from Northumberland? Or was it a completely different ring number? The bird was a little more wary, but with care Lee was able to catch it and bring it out of the box. The bird was darker, with more ashy grey feathers mixed into the soft brown feathers of the head and back, there was more spotting on the flanks and the barring on the wing was much heavier. It was an adult female. And she was ringed.
Carefully, we read and recorded the number of the ring. We make double sure and even take photos of the ring to have a record of the number. Then we check the notes from the previous visit. There is a brief pause where we hold our breath…
It is the same number! There was no doubt, this female owl was originally ringed in 2014 in a nest in Northumberland. From that point she dispersed, eventually ending up in a valley in North Wales raising her own brood of owls.
Just goes to show that we don’t quite know everything about our wildlife and there is still plenty to learn and understand about even some of our most well studied species.