By September, the plants and animals of the Northern Hemi-sphere are shifting from a growth and reproduction mode to a season of storage and survival. While late bloomers, such as asters and goldenrod, are still flowering, most deciduous plants are beginning to withdraw the sap of life from their foliage, redirecting fluid and nutrients to their roots and stems. As chlorophyll disappears from their leaves, the colors of autumn spread across the woodlands and, eventually, the dying leaves are shed, soon to be recycled on the forest floor.
Meanwhile, the hoarders of the animal kingdom, including squirrels, jays, woodpeckers, chipmunks, pikas and field mice, are gathering seeds, nuts and hay, hiding or storing these food items for use during the lean, harsh months of winter. Out in wetlands, beaver and muskrats are driven by the same survival instinct, repairing their dens and harvesting the plants that will provide food when the ponds and lakes freeze over. Hibernating mammals, such as groundhogs, ground squirrels, bats and bears, initiate a feeding frenzy during these waning days of summer, putting on the brown fat that will fuel their winter dormancy. In like manner, non-hibernating mammals take advantage of the late summer bounty to add fat and to thicken their coats, vital insulation against the frigid nights and deadly winds of the dark season.
And then there are the avian migrants, gathering at staging areas that offer high concentrations of food: seeds, berries, insects, amphibians and fish. Once supplied with nutritious fuel and stimulated by the waning daylight, they will escape to southern climes, never to experience the harsh conditions of a northern winter.