canada geese flying chesapeake bay branta canadensis bird birds dawn daybreak early ecology environment formation goose maryland blackwater migrate migration natural nature blue outdoors scenery scenic serene serenity shadow silhouette sky sunrise sun up sundown tranquil usa canadian wildfowl motion night pattern anatidae anseriformes biology birding north america ornithology  waterfowl wild wildlife sunset migrating flight md color colour mid atlantic flyway multiple abstract image concept conceptual ducks horizontal