Grassland Bird and Raptor Inventory at Harpers Ferry National Historical Park 2022 - Open Format Dataset

Harpers Ferry National Historical Park (NHP) includes grassland habitats that are maintained for the interpretation of historic Civil War battles. In 2022, as part of the National Park Service Inventory and Monitoring program, the University of Delaware conducted a grassland bird and raptor inventory in the park. The goals of this inventory were to determine the grassland bird use of Harpers Ferry grasslands during Spring and Fall migration, estimate the abundance and daily nest survival for focal breeding species, and determine the raptor use during migration. We established and used multiple avian sampling techniques to address these goals including distance sampling using line transects, mist-netting to capture passerine birds, point counts, hawk watching, and nest searching and monitoring. We conducted this inventory during the annual cycle starting in March 2022 and completed the sampling in October 2022. During the course of this effort, we detected 111 species using the Harpers Ferry grasslands at some time during the year. We found that the park is supporting migrating and breeding grassland birds and that the avian species composition changes over the course of the annual cycle. During migration, we detected focal grassland bird species including Bobolink, Savannah Sparrow, Grasshopper Sparrow, and Eastern Meadowlark. During the breeding season, we located and monitored Eastern Meadowlark and Grasshopper Sparrow nests with adequate sample sizes to estimate daily nest survival. We found that Eastern Meadowlark daily nest survival was relatively high (99%) and was influenced by the proximity of the nest to a forested edge.