The Least Sandpiper breeds across the subarctic and low Arctic in wetlands and moist tundra. They winter from the southern United States to northern South America, in both coastal and interior habitats. The Canadian breeding population is estimated at approximately 2.9 million individuals based on recent analysis of data from the Arctic Program for Regional and International Shorebird Monitoring (PRISM). This is more than four times higher than the previous global estimate, yet is likely still an underestimate, as it does not account for those breeding in the subarctic. The higher estimate is believed to reflect improved data sampling and analysis, rather than an actual increase in population. Approximately 83% of the global population breeds in Canada. The remainder of individuals breed in Alaska and pass through Canada on migration, resulting in a very high level of responsibility for Canada. The population of Least Sandpiper has shown little change relative to 1980, although confidence is low because a relatively small part of the population is sampled by migration monitoring. The national population of Least Sandpiper is within its goal range.