There has been a convergence going on down by the river. The swallowtail butterflies are enjoying the warm weather, the river and the row of blackberries that are covered in blooms. The striking black and yellow colors on their wings make for a great showing. A few admiral butterflies with their jet black, red-accented wings, join the swallowtails, they look like flying exclamation points in the field of swallowtails.
The butterflies go from fluttering around the blackberries to grouping along the waters edge, finding a landing spot along the fine rocks by the sand bar. When they land, and the fluttering becomes a slow, fan-dance. The smooth movements draw the eye to look without realizing that it is the motion of 100 or more individuals creating the calm swaying motion.
The creatures are not frightened by people, dogs or cows walking through their meetings. They just flutter around and re-land, or head back to the sweetness of the blackberry flowers.