The wires here were full of swallows, about 90% Bank. Here a Bank is flanked by a couple of Barn and a couple of Rough-winged Swallows. Bank is distinctive when perched, with that nice cigar shape seeming lacking the shoulders of a Rough-winged.
Nice shot (as always), and explanation of how to tell one from the other.
I enjoyed the shore birds too. I learn from your descriptions and how you pay attention to details. Keep'em coming!