North American Crane Working Group

 

Date of this Version

2005

Document Type

Article

Citation

Krapu, G.L., D.A. Brandt, and R.R. Cox Jr. Do arctic-nesting geese compete with sandhill cranes for waste corn in the Central Platte River Valley, Nebraska?. 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. 185-192.

Comments

Reproduced by permission of the NACWG.

Abstract

Numbers of arctic-nesting geese staging in spring in the Central Platte River Valley (CPRV) of southcentral Nebraska increased dramatically from the 1970s to the 1990s, raising concerns that geese may be competing with the mid-continental population of sandhill cranes (Grus canadensis) for waste corn. From late February to mid-April 1998-2001, we measured temporal patterns of cropland use, evaluated habitat preferences, and compared numbers of geese using the primary crane-occupied parts of the CPRV area with numbers of sandhill cranes. Numbers of Canada geese (Branta canadensis), lesser snow geese (Chen caerulescens)/ Ross’ geese (Chen rossii), and greater white-fronted geese (Anser albifrons) peaked an average of 2.3, 2.8, and 1.5 weeks before sandhill cranes, with 90% of goose numbers occurring by 21, 15, and 21 March when averaged over the 4-year period. Numbers of sandhill cranes, on average, were highest on 26 March. All bird groups used corn habitats in greater proportion than expected based on their availability (land area) and used soybean habitats less than expected. Across years, 37.5, 82.5, 53.7, and 44.3% of Canada geese, lesser snow geese/Ross’ geese, greater white-fronted geese, and sandhill cranes, respectively, occurred in quadrants in which cornfields in various post-harvest treatments constituted > 90% of the annually planted cropland. From 1998 through 2001, 0.1, 0, 0, and 2.5% of Canada geese, lesser snow geese/Ross’ geese, greater white-fronted geese, and sandhill cranes, respectively, occurred in quadrants where > 90% of the annually planted cropland was in soybeans. Overall, estimated numbers of geese annually averaged 66, 46, 39, and 62% of estimated numbers of cranes in the CPRV. When viewed in the context that arcticnesting geese rely primarily on waste corn to meet their energy needs in Nebraska and crane capacity to store fat has declined over the past 20 years, these relationships suggest geese were important competitors of sandhill cranes for waste corn in the CPRV area during 1998-2001.