Taxonomic Composition of Red Knot Fecal Samples on the Virginia Coast

• Main Authors: Karpanty, Sarah, Heller, Erin, Frasier, James, Cohen, Jonathan
• Format: Dataset
• Language: English
• Published: Environmental Data Initiative 2021
• Subjects: Barrier Island; Barrier Islands; Calidris canutus; Red Knot
• Online Access: https://dx.doi.org/10.6073/pasta/9d6961262dfdaee98720f118f5ad816c; https://portal.edirepository.org/nis/mapbrowse?packageid=knb-lter-vcr.322.1

Taxonomic Composition of Red Knot Fecal Samples on the Virginia Coast Understanding which prey birds use and how prey selection is related to prey availability is important to understanding avian ecology and for conservation planning. Abundant prey at stopovers during migration is a key to shorebird survival and breeding success. We determined which prey were available to foraging red knots (Calidris canutus rufa) using Virginia's barrier islands during spring migration by collecting substrate core samples containing prey on sand and peat substrates in May 2017 - 2019. We also collected red knot feces during the same period and used fecal DNA metabarcoding to determine which invertebrates red knots consumed. We used compositional analysis to determine which prey red knots selected on these islands. Crustaceans (Orders Amphipoda and Calanoida) were the most abundant prey on both sand and peat. Red knots consumed bivalves (Orders Venerida and Mytiloida), crustaceans (Orders Amphipoda and Calanoida), and insect larvae (Order Diptera). Red knots selected bivalves over non-bivalve prey, though non-bivalve prey may still be an important portion of the total caloric intake on Virginia's stopover, given their abundance and use. It is important that coastal conservation practices in the Western Mid-Atlantic stopover region continue to be designed to promote natural barrier island movement which leads to the formation of the peat banks used by many prey.