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Migratory bird struggles for shelter as chimneys torn down

In this Tuesday, Sept. 13, 2016 photo, migratory Vaux's Swifts are a blur as they race to roost for the night inside a large, brick chimney at Chapman Elementary School in Portland, Ore. Numbers of Vaux's Swifts are in decline, in part scientists say because of the destruction of the brick chimneys that they use to roost during their annual fall migration. (AP Photo/Don Ryan) In this Tuesday, Sept. 13, 2016 photo, migratory Vaux's Swifts are a blur as they race to roost for the night inside a large, brick chimney at Chapman Elementary School in Portland, Ore. Numbers of Vaux's Swifts are in decline, in part scientists say because of the destruction of the brick chimneys that they use to roost during their annual fall migration. (AP Photo/Don Ryan)

By Associated Press September 28, 2016 1 min read

PORTLAND, Ore. (AP) – The Vaux’s (pronounced VOX) Swift, a tiny migratory bird species, has adapted well to urban living and now roosts in old brick chimneys along the West Coast during its annual migration from Canada to Central America and back.

But the birds’ numbers are dwindling and scientists worry it may be because the pre-1940 brick chimneys the species prefers are being demolished for urban redevelopment and because of earthquake fears.

A move is afoot to build replacement towers for the birds.

The birds can fly for about 100 miles at a time between stops and must roost in large numbers in tight, enclosed spaces because their body temperature drops at night.