For the past few years, I have been staying at a motel in Terrace Bay Ontario (220 kilometers east of Thunder Bay) the night before running the Terrace Bay Breeding Bird Survey.

There always seems to be a big mud puddle in the driveway to the motel and this puddle is full of bird activity.

What is going on?

Formerly restricted to canyons, foothills, and river valleys with natural cliff faces and overhangs, Cliff Swallows have spread into a wide variety of habitats by nesting on buildings, bridges and other human-made structures. To do this they need plenty of mud.

Here is what a colony looks like.

Cliff Swallows continually flutter their wings above their backs while gathering mud.

The theory is that Cliff Swallows flutter for 2 reasons.

1. It reduces the risk of other Cliff Swallows stealing their mud.

2. Because bending to pick up mud puts the females into mating position, wing fluttering reduces the risk of mating attempts while the females are gathering mud.

Cliff Swallows were not the only birds present on this day.

Here is a European Starling bathing.

Miles Hearn