Data from: Whooping crane use of riverine stopover sites

Migratory birds like endangered whooping cranes (Grus americana) require
suitable nocturnal roost sites during twice annual migrations. Whooping
cranes primarily roost in shallow surface water wetlands, ponds, and
rivers. All these features have been greatly impacted by human activities,
which present threats to the continued recovery of the species. A portion
of one such river, the central Platte River, has been identified as
critical habitat for the survival of the endangered whooping crane.
Management intervention is now underway to rehabilitate habitat form and
function on the central Platte River to increase use and thereby
contribute to the survival of whooping cranes. The goal of our analyses
was to develop habitat selection models that could be used to direct
riverine habitat management activities (i.e., channel widening, tree
removal, flow augmentation, etc.) along the central Platte River and
throughout the species’ range. As such, we focused our analyses on two
robust sets of whooping crane observations and habitat metrics the Platte
River Recovery Implementation Program (Program or PRRIP) and other such
organizations could influence. This included channel characteristics such
as total channel width, the width of channel unobstructed by dense
vegetation, and distance of forest from the edge of the channel and
flow-related metrics like wetted width and unit discharge (flow volume per
linear meter of wetted channel width) that could be influenced by flow
augmentation or reductions during migration. We used 17 years of
systematic monitoring data in a discrete-choice framework to evaluate the
influence these various metrics have on the relative probability of
whooping crane use and found the width of channel unobstructed by dense
vegetation and distance to the nearest forest were the best predictors of
whooping crane use. Secondly, we used telemetry data obtained from a
sample of 38 birds of all ages over the course of seven years, 2010–2016,
to evaluate whooping crane use of riverine habitat within the
North-central Great Plains, USA. For this second analysis, we focused on
the two metrics found to be important predictors of whooping crane use
along the central Platte River, unobstructed channel width and distance to
nearest forest or wooded area. Our findings indicate resource managers,
such as the Program, have the potential to influence whooping crane use of
the central Platte River through removal of in-channel vegetation to
increase the unobstructed width of narrow channels and through removal of
trees along the bank line to increase unforested corridor widths. Results
of both analyses also indicated that increases in relative probability of
use by whooping cranes did not appreciably increase with unobstructed
views ≥200 m wide and unforested corridor widths that were ≥330 m.
Therefore, managing riverine sites for channels widths >200 m and
removing trees beyond 165 m from the channel’s edge would increase costs
associated with implementing management actions such as channel and
bank-line disking, removing trees, augmenting flow, etc. without
necessarily realizing an additional appreciable increase in use by
migrating whooping cranes.