beach coast coastline color colored colors colour coloured colours distance distant expanse levels low tide ocean people receded receding receding tide sand sandy sea seashore seaside shore shoreline Sizes strolling sunlight sunshine tidal tides waders wading water waterline dune-flora dunes flora grass grasses green greenery growing growth natural ocean edge ocean waterline plants rough salt-resistant sand-dunes Sandbar scrub vegetation aerial aerial roots layers mangrove growth mangroves pebbles rocks rocky root network Roots security strength strong support birds gulls pelicans seabirds seagulls waterbirds glistening glossy sand dunes blue salty summer wave footprints industrial activity industrial area Jetty outcrop pollution prints recreation relaxing rock formations shade shadows shapes ships stones stony variety