Collapse of the New York Bay scallop fishery despite sustained larval and juvenile recruitment

Abstract

Mass mortality events, due to a variety of natural and anthropogenic causes, usually result in population (and associated fishery) crashes. Recovery from such events may not occur for many years, if at all. We have witnessed a mass die-off of adult (1+ yr) bay scallops Argopecten irradians irradians in the Peconic Bays, New York, USA, from 2019-2022, with declines in population density from spring to fall of 90-99%. Similar declines in commercial landings have occurred since 2018, with severe economic consequences for fishermen. Observed mortality levels are well above those seen prior to 2019. However, since die-offs of adult scallops have been occurring after the first seasonal spawning cycle, larval and benthic juvenile (0+ yr) recruitment have remained robust through 2021. Nevertheless, with lower numbers of adults surviving to spawn in September-October, resulting in fewer fall recruits, potential buffering of marked annual fluctuations in abundance is now less likely for this short-lived species. Peconic bay scallops are again in a precarious state as these recurring die-offs, likely driven by changing environmental conditions, present further challenges to the persistence of robust populations and the likelihood of successful restoration efforts.