This article is a U.S. Government work and is in the public domain in the U.S.A.
Response of sandhill crane (Grus canadensis) riverine roosting habitat to changes in stage and sandbar morphology†
Article first published online: 12 JUN 2008
This article is a U.S. Government work and is in the public domain in the U.S.A. Published in 2008 by John Wiley & Sons, Ltd.
River Research and Applications
Volume 25, Issue 2, pages 135–152, February 2009
How to Cite
Kinzel, P. J., Nelson, J. M. and Heckman, A. K. (2009), Response of sandhill crane (Grus canadensis) riverine roosting habitat to changes in stage and sandbar morphology. River Res. Applic., 25: 135–152. doi: 10.1002/rra.1103
- Issue published online: 22 JAN 2009
- Article first published online: 12 JUN 2008
- Manuscript Accepted: 7 DEC 2007
- Manuscript Revised: 29 NOV 2007
- Manuscript Received: 1 MAY 2007
- habitat assessment;
- hydrodynamic modelling;
- instream flow;
- Platte River;
- sandhill cranes
Over the past century, flow regulation and vegetation encroachment have reduced active channel widths along the central Platte River, Nebraska. During the last two decades, an annual program of in-channel vegetation management has been implemented to stabilize or expand active channel widths. Vegetation management practices are intended to enhance riverine habitats which include nocturnal roosting habitat for sandhill cranes. Evaluating the success of other management treatments such as streamflow modification requires an understanding of how flow shapes the sandbars in the river and how sandbar morphology interacts with flow to create crane habitat. These linkages were investigated along a 1-km managed river reach by comparing the spatial pattern of riverine roosts and emergent sandbars identified with aerial infrared imagery to variables computed with a two-dimensional hydraulic model. Nocturnal observations made multiple years showed that the area and patterns of riverine roosts and emergent sandbars and the densities of cranes within roosts changed with stage. Despite sandbar vegetation management, low flows were concentrated into incised channels rather than spread out over broad sandbars. The flow model was used to compute hydraulic variables for identical streamflows through two sandbar morphologies; one following a period of relatively high flow and the other following the low-flow period. Compared with the simulation using the morphology from the antecedent high flow, the simulation using the morphology from the antecedent low flow produced a smaller quantity of available wetted area. These remote-sensing observations and hydraulic simulations illustrate the importance of considering flow history when designing streamflows to manage in-channel habitat for cranes. Published in 2008 by John Wiley & Sons, Ltd.