Lesser Yellowlegs location data describing the occurrence of birds within harvest zones in the Caribbean and South America

Shorebirds have experienced a precipitous reduction in abundance over the
past four decades. While some threats to shorebirds are widespread (e.g.
habitat alteration), others are regional and may affect specific
populations. Lesser Yellowlegs (Tringa flavipes) are long-distance
migrants that breed across the North American boreal biome and have
declined in abundance by 60-80% since the 1970s. The documented harvest of
Lesser Yellowlegs in the Caribbean and northeastern South America during
southward migration is a possible limiting factor for the species, but it
is unknown to what extent birds from different breeding origins may be
affected. To address the question of differential occurrence in harvest
zones during southward migration, we used PinPoint GPS Argos transmitters
to track the southward migrations of 85 adult Lesser Yellowlegs from
across the species’ breeding range and 80° of longitude from Anchorage,
Alaska, USA to the Mingan Archipelago, Quebec, Canada. We classified
migratory locations as inside or outside three zones with high levels of
harvest (Caribbean, coastal Guianas, and coastal Brazil) and then fit
generalized additive mixed models to estimate the probability of
occurrence of Lesser Yellowlegs in harvest zones according to their
breeding origin. Individuals from the Eastern Canada population had a
higher probability of occurrence within one or more harvest zones and
remained in those zones longer than individuals breeding in Alaska and
western Canada. Linear regressions also suggested that longitude of the
breeding origin is an important predictor of occurrence in harvest zones
during southward migration. Lastly, our findings, combined with other
sources of evidence, suggest that current estimated harvest rates may
exceed sustainable limits for Lesser Yellowlegs, which warrants further
investigation.