A Gulp of Swallows

Today I decided to go to a place near San Diego where it is possible to see several of the species of Swallow that can confuse a growing lad. They are Tree Swallow and Violet-green Swallow (Genus Tachycincta); Cave Swallow and Cliff Swallow.(Genus Petrochelidon); Barn Swallow; and Northern Rough-winged Swallow. Bank Swallow - our Sand Martin - is also on the list but mercifully not found in this area as it is so like the Rough-winged, which is so like the Tree Swallow, which is so like the Violet-green, which is so like.... To add to the confusion, different species often nest together and forage together in mixed flocks.
Add to this that now is the time when juveniles are also on the wing, and you will understand why, the sun beating down on my head and parties of schoolchildren arriving by the thousand, I decided to come home to a cool verandah and a nice cup of tea.
The swallow illustrated above is a Tree Swallow. Of course it is an adult male in breeding plumage. Adult males in breeding plumage constitute maybe a fifth of all the swallows milling around a colony or a feeding area. It's the other four-fifths that confuse a growing lad.