I hiked with my stereo gear into Castle Rock Park in Walnut Creek, California (long before the opening hour and long before astronomical twilight) and recorded several hours of the dawn chorus. Here's a snippet.
While recording in the Sierra Nevada Mountains in California with a team from the Macaulay Library at the Cornell Library of Ornithology, I captured this Rock Wren. I later discovered that it was believed to be the same bird that had been previously recorded near the same site on an earlier expedition. Apparently the portion of this bird's song that begins at about 45 seconds is quite unique and seldom heard. This recording was forwarded to a Ph.D. candidate in Mexico for analysis as part of her dissertation.
...while in the Sierras for that week long research project, I captured an elusive American Bittern (yes, that's a bird).
...and an American Bullfrog joined the otherwise bird expedition.