Northern Rough-winged Swallow

Burlington ON. May 6 2020. Northern Rough-winged Swallows are not particularly notable sighting around here, but perhaps they deserve a bit more attention. I found a pair today who had moved in to set up home in a newly-exposed cliff face.

A couple of things about Northern Rough-winged Swallows:  They are a drab looking bird certainly the least visually attractive among our swallow species, the competition is overwhelming: Barn Swallows, Tree Swallows and Cliff Swallows, all are handsome birds (See a couple of them below). It’s also interesting, I think, to consider that unusual name, Rough-winged: it refers to a unique characteristic of their primary feathers. The barbs of the leading edge of outer primaries of adult males are recurved into small hooklets, or in the case of females tiny points. So, should you have one of these birds in your hand you’d find that the edge of the wing has a file-like roughness, rough-winged actually.  No -one seem to know why this should be.

What made today’s birds a little bit more intriguing is that they have appropriated this exposed cliff face as the ideal spot to excavate a nesting burrow. The cliff face was exposed by a landslide that ripped a chunk out of a steep valley edge. I’ve been intrigued for a while by the nature of the landslide and its various impacts and was checking to see how plants and the valley in general were adjusting and adapting.

According to Aristotle, Nature abhors a vacuum, so this pair of Northern Rough-winged Swallows is apparently nature at work and that makes them My Birds of the Day.  I look forward to seeing which plant species will gain a toehold on the new terrain in the growing season ahead.