Migration path of American golden-plovers breeding across the Nearctic tundra

Many populations of migratory birds are currently declining. Understanding of space use throughout the entire annual cycle, as well as migratory connectivity (i.e., geographic linkage of individuals and populations across different stages of the annual cycle), can improve our ability to identify factors driving population declines and influencing extinction risk. The main objectives of our study were to i) document the space use and phenology of migration during the non-breeding period and ii) quantify the degree of migratory connectivity across the range of the American Golden-Plover (Pluvialis dominica) breeding across the North American Arctic. American Golden-Plovers breed across their entire breeding range (northern North America) and migrate up to their main wintering site located in South America. We used archival light-level geolocators to track the migration. We quantified migratory connectivity based on the non-breeding range spread of all individuals and the breeding population spread. We used Mantel tests to evaluate whether the relative spatial configuration of the sampled breeding area was preserved on the non-breeding ground. We identified 13 and 7 stopover sites used during the fall (post-breeding, southbound) and spring (pre-breeding, northbound) migrations, respectively, and one main site used during the wintering period. We highlight stopover sites that were previously unknown and show the transatlantic and transpacific routes used by plovers during migration. We found that individuals breeding in proximity tended to be closer to each other during brief and highly limited portions of the non-breeding period. Broadly, individuals from different breeding populations were well mixed during the wintering period and throughout most of the spring and fall migrations. Overall, the migratory connectivity of American Golden-Plovers is relatively low for most of the non-breeding period, suggesting that breeding populations separated by large distances should be similarly affected by disturbances and changes encountered at some migratory stopovers and on the wintering area.