North American Crane Working Group

 

Date of this Version

2005

Document Type

Article

Citation

Petrula, M.J., and T.C. Rothe. Migration chronology, routes, and distribution of Pacific Flyway population lesser sandhill cranes. In Chavez-Ramirez, F, ed. 2005. Proceedings of the Ninth North American Crane Workshop, Jan 17-20, 2003. Sacramento, California: North American Crane Working Group. Pp. 53-68.

Comments

Reproduced by permission of the NACWG.

Abstract

Managers of migratory game birds require accurate information about bird movements to delineate populations, protect important habitats, and regulate harvest. Data describing movements of sandhill cranes (Grus canadensis) belonging to the Pacific Flyway Population (PFP) are lacking. We used satellite telemetry to monitor movements of PFP lesser sandhill cranes (Grus c. canadensis) captured in the upper Cook Inlet and Bristol Bay regions of Alaska. Satellite transmitters were deployed on 19 flightless young (colts) and 3 adults over 3-years (2000-2002). Chronology, routes, and stopover or staging areas were identified for fall and spring migration periods. On average, cranes (n = 11) took 27 days (range = 13-44 days) to travel from summer areas in Alaska to winter areas in the Central Valley of California (CVC). Winter locations were concentrated in the Sacramento – San Joaquin River Delta and the East Grasslands (Merced County) regions. In spring, cranes (n = 10) took an average of 58 days (range = 45-65 days) to return to Alaska. In spring, most marked cranes (70%) staged at the Potholes Reservoir region in central Washington. PFP cranes that summer in Cook Inlet and Bristol Bay used identical migration routes and winter areas. Only 3 of 9 colts returning to Alaska, as juveniles, revisited their natal site. We found no evidence that PFP cranes monitored with satellite transmitters mixed with cranes from the Mid-Continent Population (MCP) or with “western segment” PFP cranes.