Distribution and abundance of Wilson’s and Snowy Plovers on Margarita, Coche, and Cubagua islands, Nueva Esparta State, Venezuela

Accurate population numbers and trends are lacking for the Wilson’s Plover Charadrius wilsonia and the Snowy Plover C. nivosus. Data from North America suggest that both species have low population sizes and negative trends that are mainly due to habitat loss and human disturbance. Within these species, two subspecies C. w. cinnamominus and C. n. tenuirostris, inhabit the Caribbean basin with unknown population sizes and trends. I have evaluated their distribution and abundance in three southern Caribbean islands (Margarita, Coche, and Cubagua) through literature reviews, citizen science, and surveys from 2006–2020. For Margarita, I have also evaluated variations in abundance given by season and locality as well as population trends for Wilson’s Plovers. Snowy Plovers have been observed at 13 localities: eight in Margarita, four in Coche, and one in Cubagua. Margarita and Coche supported similar numbers of Snowy Plovers with maximum counts of around 40 birds on each island, among the highest abundances reported for C. n. tenuirostris. Wilson’s Plovers were recorded at 22 localities in Margarita, six in Coche, and five in Cubagua. Highest numbers were hosted by Margarita, with maximum counts ranging from 170 birds in 2006 to 51 in 2014. A negative population trend, with a decline of 61% in nine years, was estimated. Seasonal variations in abundance suggest that both species undergo seasonal movements. Although further research is needed to estimate regional population sizes, data from this work suggest that Margarita may host more than 1% of the population of C. w. cinnamominus currently estimated at 6,500–8,500 individuals, while both Margarita and Coche host more than 10% of the population of C. n. tenuirostris currently estimated at less than 200 individuals. Coordinating efforts for simultaneous censuses and banding programs within the Caribbean seems to be a research priority that would help to identify other key sites and obtain reliable population estimates for these subspecies.