Data from: Feather corticosterone is lower in translocated and historical populations of the endangered Laysan duck (Anas laysanensis)

Identifying reliable bioindicators of population status is a central goal
of conservation physiology. Physiological stress measures are often used
as metrics of individual health and can assist in managing endangered
species if linked to fitness traits. We analysed feather corticosterone, a
cumulative physiological stress metric, of individuals from historical,
translocated, and source populations of an endangered endemic Hawaiian
bird, the Laysan duck (Anas laysanensis). We hypothesised that feather
corticosterone would reflect the improved reproduction and survival rates
observed in populations translocated to Midway and Kure Atolls from Laysan
Island. We also predicted less physiological stress in historical Laysan
birds collected before ecological conditions deteriorated and the
population bottleneck. All hypotheses were supported: we found lower
feather corticosterone in the translocated populations and historical
samples than in those from recent Laysan samples.  This suggests
that current Laysan birds are experiencing greater physiological stress
than historical Laysan and recently translocated birds. Our initial
analysis suggests that feather corticosterone may be an indicator of
population status and could be used as a non-invasive physiological
monitoring tool for this species with further validation. Furthermore,
these preliminary results, combined with published demographic data,
suggest that current Laysan conditions may not be optimal for this
species.