MEPS prepress abstract   -  DOI: https://doi.org/10.3354/meps14741

ABSTRACT: White shrimp (Penaeus setiferus) and brown shrimp (Penaeus aztecus) are key predators of benthic infauna and important prey resources for higher trophic levels in coastal waters of the southeastern United States. Both species rely on estuaries as nursery habitat and are subject to the dynamic environmental conditions typical of these ecosystems. Understanding the phenology of juvenile penaeid shrimp estuarine habitat use, detecting changes in phenology over time, and linking interannual variability in phenological metrics to environmental conditions will provide improved understanding of the degree to which global change is impacting the life history of these key members of estuarine communities. We analyzed nearly four decades of catch data (1984 to 2022) from a tidal creek in South Carolina, USA, comparing the timing, synchrony, and duration of juvenile shrimp habitat utilization across years to identify shifts in phenology. We then investigated linkages between environmental and climatological conditions and shrimp phenology to understand potential drivers of interannual variation in these metrics. Brown shrimp phenology showed no directional change over time; however, salinity and winter water temperature were strong predictors of variability in all three phenological metrics. Conversely, white shrimp nursery habitat use has become less synchronized and occurs over a longer interval, but no single environmental variable strongly predicts all three metrics. Differences in life history strategy and environmental tolerances likely contribute to the variation in phenological responses observed for these species. Our findings demonstrate that climate change related shifts in phenology will be species and life history specific.