a lot action air anatidae animal anseriformes back light bird black blackwater brackish branta canadensis Cambridge canada goose chesapeake bay clear cold color colour creek distant dusk evening flight flock fly flying formation gander geese golden goose group heading horizon image landscape many marsh marshland maryland md migration migratory mirror movement national national wildlife refuge nightfall november october orange outdoors park reflection refuge river scenic shadow silhouette sky south speed still stillness sundown sunset tidal tide together tranquil tranquility tree trees tributary twilight USA water waterfowl wetland wetlands wildlife