Distribution and abundance of Snowy Plovers in eastern North America, the Caribbean, and the Bahamas

Abstract

Snowy Plovers (Charadrius alexandrinus) are small, partially migrant shorebirds that are broadly distributed across North America. Snowy Plover distribution west of the Rocky Mountains has been well described. However, distribution and abundance east of the Rocky Mountains has not received much attention despite current status and ESA listing concerns for Snowy Plovers in the southeastern United States and the Caribbean. Thus, a first step in developing a monitoring program for Snowy Plovers is to understand the species' distribution. We summarize information on distribution and abundance of Snowy Plovers in the eastern United States, Caribbean, and Bahamas. Breeding and winter distribution maps for the continental United States were generated from a database of 3563 records from 388 sites in continental North America constructed from International Shorebird Survey (ISS), Christmas Bird Count (CBC), unpublished field data, and published accounts. Comparison of maximum counts per site (1980–present) indicated the number of breeding Snowy Plovers was greatest in Kansas and Oklahoma, while the greatest number of wintering birds occurred in the Laguna Madre of Texas and Mexico. Snowy Plovers concentrate at sites in Oklahoma and Texas during migration, with higher concentrations on the upper Texas coast in spring compared to fall migration. Data regarding historic abundance and trends are limited but suggest that Snowy Plovers in the eastern United States may have experienced regional population declines and may have suffered a range contraction in Texas. Serious concerns about the conservation status of Snowy Plovers in the eastern United States, the Caribbean, and the Bahamas indicate an immediate need for systematic surveys and up-to-date population estimates.