The Cassin's Sparrow, a bird of arid grasslands, has a delightful song that features a trill followed by four high whistles with a high-low-high-low pattern, like the main song of the Carolina Chickadee, but much higher in frequency. I found these birds by the roadside in New Mexico. With no place but a narrow shoulder to park, I didn't linger long enough to get a good sample, but between the passing cars are several nice songs. The featured cut has eight songs and three cars. This male used two song-types, one noticeably higher in frequency than the other, in the pattern HLLHLHLL. You can also hear at least one other Cassin's Sparrow singing in the background. For other song-types at this location, go to the other two recordings on the eBird checklist. And, for a thoughtful exploration of the place of the Cassin's Sparrow in the world, try the website cassinssparrow.org.
The namesake of this species is John Cassin, curator at the Philadelphia Academy of Natural Sciences during the age of western exploration by the U.S. government, in the mid-nineteenth century. He named many species of birds discovered on those expeditions, and five were named after him. He has a sparrow, a finch, an auklet, a kingbird, and a vireo to his name. All occur primarily in western North America.
Also on this date, in 1996, I was in the spruce woods of Islesboro, Maine. True to form, warblers were much in evidence. I recorded Nashville, Tennessee, Ovenbird, Black-throated Green, Magnolia, and Myrtle. Those names are interesting for birds of the north woods, aren't they? Four of the six were first encountered on migration or on their winter ranges, which led to their English names. While not exactly misnomers, these names tell us nothing about the birds' appearance, behavior, or breeding habitat. The easiest way to hear and see the recordings is to go directly to the eBird list.