Even juvie Black Terns. These ones are resting on one of plastic tubings that kids use to beat each other with in the water (maybe that's just my kids).
Black Terns don't plunge into the water, this one is flaring up to dip down for some surface item. This behaviour can be pretty helpful on those usual occasions when they're flying past a mile out from Tiscornia.
From beneath the birds don't look that black, this is a montage of 2 of Tim's shots.