Tree Swallow (Tachycineta bicolor)
The tree swallow is the only swallow described in this section that does not breed in Europe. The breeding range of this bird that closely resembles the common house martin is restricted to all of Canada south of the northern tree limit and parts of the USA (north of the line from southern California to Virginia crossing western Colorado, northeastern Kansas and Louisiana). It winters in Central America (including Mexico), Cuba and parts of the southern USA.
When not breeding it is a very sociable bird that lives and migrates in large flocks. In December of 2009 a flock that was estimated at one million birds - a very large flock indeed - was observed in the vicinity of Vacherie, Louisiana, USA.
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