DIETARY FLEXIBILITY OF SHOREBIRDS IN THE WESTERN-HEMISPHERE

Regional patterns of shorebird diets were examined by reviewing 75 pap ers reporting prey of 43 shorebird species throughout the western hemi sphere. Collectively, shorebirds consumed a wide variety of invertebra te taxa, including 12 phyla, 22 classes, 72 orders, 238 families, and 404 genera of invertebrates. The most widely represented invertebrate classes were Insecta, Malacostraca, Gastropoda, Polychaeta, and Bivalv ia. The ten most widely studied shorebird species exhibited considerab le dietary breadth, consuming an average of 36 (range 23-65) families of invertebrates. Fifteen invertebrate families were common to the die ts of seven or more of these ten species. For all shorebird species ev aluated, there was little dietary overlap in invertebrate taxa between geographic regions, especially between tidal and inland areas. Diet s imilarities of species and guilds of shorebirds within regions and of coexisting species within studies were high. The flexible nature of fo od choice in shorebirds influences management approaches toward provid ing vital food resources for shorebirds during all seasons. Management efforts should focus on maintaining hydrologic regimes and ecosystem processes that promote the growth and maintenance of invertebrate popu lations in general; specific taxa need not be targeted. Successful mai ntenance of wetlands will ensure that naturally-occurring populations of invertebrates occur and are accessible to shorebirds.