Review of the Status of the Yellow-Billed Cuckoo in California: Sacramento Valley Populations

Abstract

Decline in populations of western race of Yellow-billed Cuckoo (Coccyzus ameri.. canus occidentalis) in California was noted by Grinnell and Miller in 1944, who stated: because of removal widely of essential habitat conditions, this bird is now wanting in extensive areas where once found. The paucity of recent records (table 1) has led ornithologists to speculate that Yellow-billed Cuckoo may presently be absent from much of its former range. Guy McCaskie (pers. comm.) suggests that area above Laguna Dam on Colorado River may be the last stronghold for Yellow-billed Cuckoo in California. The relative scarcity of reports in recent years may not reflect Yellow-billed Cuckoo's status since this species arrives late in spring (late May and June), nests in areas seldom visited by field ornithologists, and is furtive and thus easily overlooked. During July and August 1972, I located Yellow-billed Cuckoos at 15 localities along Sacramento River in Sacramento Valley, California (fig. 1). This paper presents data on status and habitat of this population and reviews information concerning past and present status and distribution of Yellow-billed Cuckoo in California region.