What is Angelina doing in the story's opening? The Bird Thing

The story begins with the “you”(Angelina) smoking “the first of your birthday cigarettes” (164) and trying not to think about the bird thing. Angelina checks on the bird thing by checking to see if “the banana [she] nailed to the trunk [of a lime tree] is still there” (165). The banana is there with a bite taken out of it. Angelina leaves a slice of orange from her apron, puts it on top of the banana, and goes inside.