Cranes — Family Gruidae
Sandhill Crane Grus canadensis
At the turn of the 20th century, Sandhill Cranes migrated over southern California in numbers, stopping at least occasionally, perhaps more often in the Los Angeles basin than in San Diego County. A century later, such flocks are ancient history, and the cranes winter at only three sites in the region, the Carrizo Plain, the Imperial Valley, and the Palo Verde Valley along the Colorado River. Since 1920 there have been only three specific records for San Diego County.
Migration: Of the three recent records of wild Sandhill Cranes in San Diego County, one was of a fall migrant flying over south San Diego Bay along the Silver Strand (T9) 4 December 1999 (D. Parker, NAB 54:104, 2000), the other two were of spring migrants, in the east basin of San Elijo Lagoon (L7) 26 April 1998 (M. Baumgartel) and in the San Luis Rey River valley near Bonsall (E8) 28 February 2000 (P. A. Ginsburg, NAB 54:221, 2000). The only other report since the early 20th century was of seven at Cuyamaca Lake 24–30 September 1977 (AB 32:357, 1978).
In one of the more bizarre episodes in the history of San Diego County birds, a tame Sandhill Crane fitted with a radio transmitter showed up on the lawn of an apartment complex near the corner of Telegraph Canyon and Otay Lakes roads (U12) 23–26 November 1998. It had been raised in captivity and released in northeastern Arizona as part of an experimental reintroduction program.
Conservation: Unfortunately, the early naturalists in southern California left us only meager information on the Sandhill Crane. Emerson (1887) saw large flocks flying over Volcan Mountain 16 and 20 March 1884. Grinnell et al. (1918) reported that at Campo “many flocks have been seen passing high overhead in a southeasterly direction which would have led them to the head of the Gulf of California, where the species is known to winter abundantly. In early spring flocks have been noted traversing the same course in reverse direction.” Stephens (1919a) wrote, “the cranes migrate in considerable flocks in fall and spring, often without stopping in the county. Occasional in winter on grass and grain fields.” The species was decimated by hunting and habitat changes, extensive grasslands and grain fields now being things of the past. The desiccation of the Colorado delta following the river’s damming eliminated the crane’s primary winter habitat in the region.
The number of Sandhill Cranes wintering in the Imperial Valley began increasing in the 1990s (Patten et al. 2003). The increase may account for the occurrences in San Diego County in 1999 and 2000 and may foreshadow more frequent occurrences in the 21st century, though the species’ future in southern California is at the mercy of agricultural water and land-use policies.
Taxonomy: No specimen was ever collected in San Diego County, so the subspecies occurring here is (are?) not known. In the Imperial Valley the Lesser Sandhill Crane, G. c. canadensis (Linnaeus, 1758), predominates, but the Greater, G. c. tabida (Peters, 1925), has also been seen and collected there.