Abstract
Aim: To test whether the occupancy of shorebirds has changed in the
eastern Canadian Arctic, and whether these changes could indicate that
shorebird distributions are shifting in response to long-term climate
change Location: Foxe Basin and Rasmussen Lowlands, Nunavut, Canada
Methods: We used a unique set of observations, made 25 years apart,
using general linear models to test if there was a relationship between
changes in shorebird species’ occupancy and their Species Temperature
Index, a simple version of a species climate envelope. Results: Changes
in occupancy and density varied widely across species, with some
increasing and some decreasing. This is despite that overall population
trends are known to be negative for all of these species, based on
surveys during migration. The changes in occupancy that we observed were
positively related to the Species Temperature Index, such that the
warmer-breeding species appear to be moving into these regions, while
colder-breeding species appear to be shifting out of the regions, likely
northwards. Main Conclusions: Our results suggest that we should be
concerned about declining breeding habitat availability for bird species
whose current breeding ranges are centred on higher and colder
latitudes.