This video from North America is called American Redstart & Blue-winged Warbler.
From the Smithsonian Migratory Bird Center in the USA:
by Gregory Gough (May 2008)
When a young American redstart makes its first flight south from its breeding grounds in eastern North America, its choice of wintering grounds in Central and South America is a decision that will affect the rest of its life.
Unknown to them, the impending dry season will greatly reduce the amount of food and water available in the scrub habitat while the mangrove habitat will remain lush and abundant.
A Good Start for Redstarts
By the time spring migration commences in early April, the young redstarts that wintered in mangrove habitats are fit and loaded with fat to help them migrate to their breeding grounds.
They head north from Jamaica and choose the first suitable habitat they find, one where the leaves are just emerging and insect food is abundant.
In contrast, redstarts that wintered in scrub habitats are not yet ready to migrate and need more time to build up their fat reserves. By the time they do arrive on the southern breeding grounds they find them occupied by other redstarts and must fly further north to nest.
Adult redstarts return to the same breeding and wintering sites year after year, it is only in that first fall that the young redstarts choose their wintering area, which influences their choice of where they breed.
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