...The birds have to pick up the worms with potholders.

Each season is not only a span of time, which all creatures experience in common, but also a program, a plan of work, a set of tasks and traditions, that belong to each kind more particularly. What those tasks are and how they progress define the season as much as the calendar does.
By the end of July, our own human summer is most fully itself in its sensations, its associations, in the structure it imposes on our lives. Being outdoors, gardening, mowing the grass, getting out on the water , traveling: The activities that summer permits us, and those it demands of us, are now perfectly familar and become the meaning of the season as much as any grand solar interval or pattern of weather. For us, moreover, that meaning has to do with a measure of freedom, of relative ease.
That's our summer, but perhaps it's ours alone. Summer for the birds, for example, though it occupies the same weeks, it is a very different season. It's a hectic, exhausting race to hatch, rear, fledge, and lauch the new generation. By our midsummer, that race is nearly run. The nests are abandoned; they began to fall apart. The young of the year are mostly on their own. A few species-including some of the small songbirds-have already left for the south. When the human summer is fairly getting in top gear, the birds' summer is for all practical purposes, over.