These are photos of emerging & newly emerged (teneral) Spiny Baskettails, taken at Blue Lake in Lassen County on June 9, 2009 by Steve Rottenborn.
Steve found 400+ in a relatively limited portion of the lake's shoreline near the boat ramp. When he arrived at 11:30, he saw only a few flying tenerals, with most emerging as nymphs from the lake or emerging from exuviae, which were densely packed on emergent sedges and rushes, rocks, logs, tree trunks, and shrubs. He found that although emerging individuals were concentrated closest to the shoreline (i.e., within 5 m or so of the lake edge), nymphs were also found as much as 20 m from the lake still walking upslope. Densities in some sedges along the lake edge were as high as 20/square meter. He found very few exuviae that did not have a baskettail next to or emerging from it when he arrived, so he may have caught this emergence on its first big day. By 15:00 when he left, many tenerals were flying away from the lake. He would have expected higher densities of avian predators taking advantage of this emergence than he saw, but a few American Robins, Western Tanagers, Brewer's Blackbirds, and Red-winged Blackbirds were depredating baskettails heavily. He watched one robin eat six baskettails, taking some that were still only partially emerged from their exuviae, then grab two more and fly off with both in its bill, all in the space of less than two minutes.