WOOD WARBLERS AND VIREOS IN CALIFORNIA: THE NATURE OF THE ACCIDENTAL

Abstract

Joseph Grinnell (1922) wrote, “it is only a matter of time theoretically until the list of California birds will be identical with that for North America as a whole.” This prediction is being rapidly fulfilled. However, the many records of “accidentals” obtained in California since 1922 suggest that we should reexamine the application of that term, particularly as applied to such species in California. Specifically we here ask whether the records of accidentals are without pattern, or whether they are in general predictable on the basis of zoogeographic and/or ecological characteristics of the species involved.