Northern Rough-winged Swallow

Northern Rough-winged Swallow - A Rare New Brunswick Swallow

Northern Rough-winged Swallow [Internet Photo]

Last week a Northern Rough-winged Swallow (Stelgidopteryx serripennis) was seen at Welsford.  This is a rare swallow species to be found in New Brunswick.  'Birds of New Brunswick: An Annotated List' lists it as a rare summer resident and visitor.  In past years it has been found breeding in southwestern NB, east to the St. John River and north to Carleton County.  There have been a few scattered sightings in other parts of the province.  

I have seen this species at Scotch Lake, York County, in 2009.  It was a single bird flycatching and perching on wires with Tree Swallows.  It often associates with Bank Swallows and can easily be overlooked since they are similar looking.  

Northern Rough-winged Swallow [Internet Photo]

The Northern Rough-winged Swallow is 13 cm long (5 inches) about the size of the Bank Swallow.  It is a rather drab-looking swallow with brown upperparts, pale brownish throat and breast and white underparts.  Its tail is square.  It is named for the serrations on the first primary wing feathers which can be seen in the photo above.  These are only visible with the bird in hand.  This apparently is a unique feature among birds.  The Greek genus name, Stelgidopteryx, means 'scraper wing' and the Latin specific name, serripennis, means 'saw feather'.  The purpose of these serrations is not known.

Northern Rough-winged Swallow

The Northern Rough-winged Swallow occupies a large summer range in North America, most of British Columbia, most of the very southernmost part of the rest of Canada, and all of the US.  In winter it migrates to Mexico, southern California, and the Gulf Coast  of Texas and Florida.  It nests in cliffs along river banks and underneath bridges.  It builds tunnels in sand banks or it will use natural cavities.  It lays 4 to 8 white eggs which are incubated for 12 days by the female.  The diet is mainly insects caught in flight.  It will take insects from a water surface and it drinks by skimming the water surface.  

Northern Rough-winged Swallow

As you can see by its preferred nesting areas how easy it is to overlook this species when it is with a  flock of Bank Swallows.  The Bank Swallow, however, has a clean white throat and belly with a brown breast band.  Occasionally it might be mistaken for an immature Tree Swallow but the Tree Swallow has a white throat and an indistinct breast band which does not meet in the middle.  The call note of the Northern Rough-winged Swallow is a low, unmusical 'brrrt' sound.  

The Northern Rough-winged Swallow was first described by John James Audubon in 1819 in Louisiana.  This rather rare swallow is interesting and worth looking closely for the next time you see a flock of Bank Swallows.