Coastal Bird Reproductive Metrics and Distribution in Alabama: A Review of Historical Data and Status Update

Abstract

A holistic approach to monitoring reproductive success of birds includes determining numbers of pairs, nests, chicks, and fledglings. Long-term monitoring will elucidate potential changes in the breeding population size and distribution, and possibly the causes of those changes. Further, monitoring in all stages of the reproductive cycle will help identify which stage might be limiting population growth. To assess the historical breeding populations of coastal birds in Alabama, we conducted a literature review and summarized data on reproductive metrics for American Oystercatcher (Haematopus palliatus), Black Skimmer (Rynchops niger), Least Tern (Sternula antillarum), Reddish Egret (Egretta rufescens), Snowy Plover (Charadrius nivosus), and Wilson's Plover (Charadrius wilsonia). We found 287 records from 20 sources with various metrics reported, including number of adults, pairs, nests, chicks, and fledglings, and 92 eBird records. We compared historical records to data collected during 2018–2021 to determine if and how breeding populations changed. We also compared historical and recent nesting distribution along the Alabama coast. We discuss apparent changes in breeding population sizes and potential reasons for changes in distribution, and use recent data on breeding population size and reproductive success to assess how it relates to the current conservation status of each species in Alabama.