 Both Smith Creek and Arroyo Hondo were recorded in 1905 by John Otterbein Snyder as holding anadromous Steelhead trout ("Oncorhynchus mykiss") streams.Impassable falls are present on upper Arroyo Hondo, but the rainbow trout in Smith and Isabel creeks are assumed to be native, as California roach ("Hesperoleucus symmetricus") and Sacramento sucker ("Catostomus occidentalis occidentalis") are also present above and below the falls.Speckled dace ("Rhinichthys osculus") were collected by John Otterbein Snyder in 1905 in Arroyo Hondo and Isabel creeks, but not by Scoppettone and Smith in 1978, having disappeared from most of their former sites in the central coast.