NORTH AMERICAN CRANE WORKING GROUP
HOME ABOUT NEWS WORKSHOPS PUBLICATIONS AWARDS JOIN CONTACT

PROCEEDINGS OF THE NORTH AMERICAN CRANE WORKSHOP

Volume 12 : < Previous article   Next article >

Title:
CHARACTERISTICS OF SANDHILL CRANE ROOSTS IN THE SACRAMENTO-SAN JOAQUIN DELTA OF CALIFORNIA


Date: 2014


Authors:
GARY L. IVEY, Oregon State University and International Crane Foundation
BRUCE D. DUGGER, Oregon State University
CAROLINE P. HERZIGER, Oregon State University
MICHAEL L. CASAZZA, USGS Western Ecological Research Center
JOSEPH P. FLESKES, USGS Western Ecological Research Center

DOWNLOAD
DOWNLOAD COMPLETE ARTICLE


Citation:
Ivey, G. L., B. D. Dugger, C. P. Herziger, M. L. Casazza, and J. P. Fleskes. 2014. Characteristics of sandhill crane roosts in the Sacramento-San Joaquin Delta of California. Proceedings of the North American Crane Workshop 12:12-19.

Abstract:
The Sacramento-San Joaquin Delta (Delta) region of California is an important wintering region for 2 subspecies of Pacific Flyway sandhill cranes (Grus canadensis): the Central Valley Population of the greater sandhill crane (G. c. tabida) and the Pacific Flyway Population of the lesser sandhill crane (G. c. canadensis). During the winters of 2007-08 and 2008-09 we conducted roost counts, roadside surveys, aerial surveys, and tracked radio-marked birds to locate and assess important habitats for roosting cranes in the Delta. Of the 69 crane night roosts we identified, 35 were flooded cropland sites and 34 were wetland sites. We found that both larger individual roost sites and larger complexes of roost sites supported larger peak numbers of cranes. Water depth used by roosting cranes averaged 10 cm (range 3-21 cm, mode 7 cm) and was similar between subspecies. We found that cranes avoided sites that were regularly hunted or had high densities of hunting blinds. We suggest that managers could decide on the size of roost sites to provide for a given crane population objective using a ratio of 1.5 cranes/ha. The fact that cranes readily use undisturbed flooded cropland sites makes this a viable option for creation of roost habitat. Because hunting disturbance can limit crane use of roost sites we suggest these 2 uses should not be considered readily compatible. However, if the management objective of an area includes waterfowl hunting, limiting hunting to low blind densities and restricting hunting to early morning may be viable options for creating a crane-compatible waterfowl hunt program.

The North American Crane Working Group provides free and open access to articles in Proceedings of the North American Crane Workshop. No additional permission is required for unrestricted use, distribution, or reproduction in any medium, provided that the original work here is properly cited. Complete Proceedings are also available for download or purchase.

© 2014 North American Crane Working Group