Anthropogenic climate change is rapidly altering environmental conditions that influence the distribution of earth’s biota and define its zoogeographic realms; the effect is most pronounced in the arctic. To better understand current habitat preferences, I monitored nests and investigated nesting habitat composition for Semipalmated Sandpiper, (Calidris pusilla, n = 326), Dunlin (C. alpina, n = 41), Pectoral Sandpiper (C. melanotos, n = 54), Red Phalarope (Phalaropus fulicarius, n = 60), Red-necked Phalarope (P. lobatus, n = 42), Ruddy Turnstone (Arenaria interpres, n = 13), and Black-bellied Plover (Pluvialis squatarola, n = 20) on the Colville River Delta, Alaska, USA, between 2015 and 2016. I assessed a suite of in situ habitat composition variables at nests and random sites. I utilized these data to ground truth an unsupervised classification of remote-sensing imagery (1.8 m2 resolution) and model habitat and social variables ascertained ex situ to explain shorebird nest site selection.
Semipalmated Sandpipers, the most abundant shorebird on the delta, disproportionately selected mesic graminoid herbaceous habitats (77%) compared to availability. Key habitat characteristics that explain variability in shorebird nest sites include dominant plant species cover-abundance, soil moisture, and micro-elevation. My goal is to illustrate the variable needs and preferences of different Arctic-breeding shorebirds at a finer scale than established in shorebird ecoloy literature, and to better inform modelling of potential climate change influences and management strategies for these species and their habitat.