Spatiotemporal Variation in Habitat Suitability Within a Major Producing Area for Age-0 Atlantic Striped Bass, Morone saxatilis

Abstract

Estuarine environments are recognized as critical nursery habitats that are necessary to sustain overall fish production. Striped bass Morone saxatilis support recreational and commercial fisheries along the Atlantic coast of the United States, and annual surveys to assess juvenile (age-0) abundance in Chesapeake Bay, the major producing area for the population, have long been used in management. Factors that contribute to high juvenile abundance are not fully understood. We used catch data from fishery-independent surveys coupled with hindcasts from a pair of numerical models to quantify the extent of summer habitats used by age-0 striped bass throughout Chesapeake Bay for 1996–2017. Specific conditions that defined habitat suitability for age-0 striped bass varied throughout the summer and among years, reflecting changes in water quality and habitat use. Shallow, nearshore areas throughout the Bay consistently supported suitable conditions for age-0 striped bass, but the estimated extent of suitable habitat varied annually at both regional and local, tributary-specific, scales. Although the areal extent of suitable habitat Bay-wide in early summer declined since 1996, fish production was not limited. Nonetheless, a pattern of increasing relative abundance of age-0 striped bass with greater extent of suitable habitats in Chesapeake Bay was observed, suggesting that the availability of suitable habitats at the scale of individual tributaries and Bay-wide may play an important role in production of this estuarine-dependent species.