Rivers tend to move slower have warmer waters than the rapidly moving streams.
There are rapidly moving streams, which are associated with mountainous areas, and the slower moving streams which have a slight gradient. Most streams have slippery rocks that are coated with algae. Rivers and streams are bounded with mature trees, hollow trees, grasses, weeds, bushes, ferns and wildflowers. While not as rich in waterbirds as lakes or ponds and marshes , rivers provide homes for several other species such as the Common Merganser, herons, sandpipers and gulls. Along wooded riverbanks, you can find Northern Orioles, warblers, vireos and wrens.