The first rays of dawn are beginning to illuminate the night sky, and a determined Black-throated Green Warbler is exhausted after her arduous nocturnal journey. She has left her wintering grounds in Central America two weeks ago and is in a race against the clock to make it to her breeding grounds in the boreal forest, where the males are already anxiously awaiting her arrival. She and her mate will have only one shot to raise a family this season, before they must once again retreat to their tropical wintering grounds.

She desperately needs to find a place to rest and refuel after having covered well over a hundred kilometers during the night. As she scans the scene below her, a welcoming patch of green nestled in an otherwise barren landscape of buildings and asphalt catches her eye. She should be able to find something to eat there.

Touching down in the mature trees of a suburban neighbourhood, she begins working through the branches, happily picking off unsuspecting insects. After a time, she notices another patch of promising trees several meters away, for some reason surrounded by brick.

She takes off from her perch and darts towards the trees. Milliseconds before crashing into a window reflecting the trees she just left, she notices what appear to be tightly spaced white dots blocking her path. Startled, she veers sharply to avoid impact and lands safely in another group of trees beside the house.

She continues her search for food until night falls, and she once again takes to the sky.