Northern Rough-winged Swallow

Rough-winged Swallows get their name from an unusual modification of their outermost wing feather. The tips of the barbs on the leading edge of this feather are stiff and project outward to a varying degree (more in males than females), rather than being flush with the rest of the feather. The reasons for this structural difference remain unknown.

The Northern Rough-winged Swallow is a relatively uncommon species primarily associated with rivers. It is often confused with the highly colonial Bank Swallow but is slightly larger, paler brown, and lacks the latter’s distinct breast band. The two species often occur together, although there are rarely more than one or two rough-winged pairs within a Bank Swallow Colony. Like Bank Swallows they nest in burrows, although they are not believed to excavate these themselves. Instead, they use old Bank Swallow or kingfisher burrows, and also nest regularly in man-made structures such as drainpipes under bridges and even the tail pipes of parked vehicles.

Unlike New Hampshire’s other swallows, the Northern Rough-winged is not showing as strong a population decline. Although the species is rare overall on the Breeding Bird Survey, numbers increased somewhat from the 1960s to the early 1990s, but since then have shown a consistent decrease to the point that current numbers are close to the starting point. Why rough-winged swallows are not declining as strongly is unknown. Because they winter in Central America it’s possible that their shorter migration distance is a factor, although the declining Teee Swallow has an even shorter journey. Perhaps their foraging behavior also makes a difference: rough-wings forage closer to the water and ground than other swallows and may thus be eating different insects or are less vulnerable to weather variation that limits insect activity.