Algae on the other hand, remain photosynthetic all winter long, or survive as spores in a dormant state. Along the water's edge, chlorophyll is being broken down from the leaves of deciduous trees and shrubs during the winter months. This is why the leaves change colors in the fall- they are dying. Before these leaves drop from the limbs, though, they sprout winter buds that carry embryonic leaves and flowers through the period of winter dormancy. Although deciduous trees don't grow during the winter, conifers do perform photosynthesis when the temperature rises above freezing.
Mallard ducks stay near ponds as long as there is some open water.
They can swim in cold water and stand on ice because they have thick feather insulation and their feet are adapted to keep out the cold. In contrast, many other species of birds migrate when the weather begins to chill. A few kinds of butterflies do as well. Cold-blooded toads, water snakes, and garter snakes head under decaying logs, in stone piles, burrows, or other holes, and hibernate. Raccoons only become active on mild days, on cold ones they hibernate in their dens.