Temporal Patterns of Migration and Spawning of River Herring in Coastal Massachusetts

摘要: AbstractMigrations of springtime Alewife Alosa pseudoharengus and Blueback Herring A. aestivalis, collectively referred to as river herring, are monitored in many rivers along the Atlantic coast estimate population sizes. While these estimates give an indication annual differences number returning adults, links subsequent timing duration spawning freshwater juvenile productivity remain equivocal. In this study, we captured herring at night 20 coastal Massachusetts lakes using a purse seine extracted otoliths derive daily fish ages back-calculate spawn dates. Estimates dates were compared with fishway counts migrating adults assess migration spawning. We observed distinct delay between beginning adult run start spawning, ranging from 7 28 d across lakes. Spawning continued 13–48 after stopped into freshwater, fur...