What does bird imagery mean in hotel world?

At the end of the novel, the image of birds landing on trees in a garden (presumably the garden of the girl who works in a watch shop) is repeatedly invoked as a symbol for continuing life. Despite the fact that it is the middle of winter, the birds still find wild strawberries to eat, and still descend upon the garden and on the branches of the rain-soaked trees. In this manner, Smith uses the birds as a manner of communicating the renewed sense of hope in Clare; she has not forgotten Sara, nor will she, but she has learned to accept that she is gone, and that her own life must carry on — even through the hardest of times.