Northern Rough-wing Swallow from Baja Mexico

If you live between southern Canada and Panama you have probably seen this species of swallow. A slim plain brown colored bird flying low, catching insects on the wing. He is one of about 10 swallow species in the family Hirundinidae

This species – Northern Rough-winged Swallow – Steldigopteryx serripennnis – is so named for the tiny hooks found on the outer tips of the primary feathers. The purpose of these hooks are unknown but is thought to produce a particular sound in flight.

Here the bird spreads out his feathers while preening and I get a chance to check for the ‘hooks’ on the primary feathers. I cant make out anything.

072212 03 Small — With primary feathers spread out

Looking as close as I can, I do not see any ‘hook’ on the primaries. Perhaps it is necessary to hold the bird in hand to see the hooks. At any rate, the Northern Rough-winged Swallow nests in dug out burrows, much like the cliff and bank swallows. The male and females use their feet ti dig burrows from one foot to three feet in depth, with a one foot diameter chamber at the end. The female incubates for twelve days, and both parents feed the brood for 19 to 14 days.