Trends in Abundance of Semipalmated Sandpipers: Evidence from the Arctic

Counts of Semipalmated Sandpiper (Calidris pusilla) at some migratory stopover sites have shown pronounced declines over the last 35 years. Counts from breeding grounds avoid sources of bias that have proven troublesome for trends estimated from migration surveys. Published and unpublished data were reviewed to examine trends in densities of Semipalmated Sandpipers at breeding sites across Alaska and arctic Canada. Information was sparse, and some comparisons are tenuous because methods varied over time. Valid time series were obtained for 13 sites across the species' range. In Alaska, Semipalmated Sandpipers either increased or were at least stable at six sites and decreased at one site. Surveys at both sites in the central portion of the range suggested no change in abundance. In the eastern portion of the range, trends were variable: decreases were observed at two sites, a possible increase at one site, and no change at another. Thus, the species was generally increasing or stable in the west...