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Posts tagged “Mud Nests

Cliff Swallow

The nesting habits of Cliff Swallows are fairly unusual in that these swallows are colonial nesters.  Here in the East you can find 20 or 30 of their nests under a bridge or the eaves of a barn (and occasionally on cliffs).  In the West, colonies consist of up to 3,500 nests! The construction of their gourd-shaped nest requires between 900 and 1,200 trips to mud puddles or stream banks, where they gather a mouthful of mud in the form of a pellet.  Often two swallows will build nests side-by-side, sharing the wall of mud that separates them. Unfortunately, according to the most recent Vermont Breeding Bird Atlas, the Cliff Swallow population in Vermont has declined by 48% in the past 25 years, a fact which is attributed to competition with House Sparrows, a decline in insects due to diminishing farm land, and destruction of nests by humans.  These birds are more important insect predators than ever, with the bat population having suffered such a decline recently due to white-nose syndrome.