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Causes of recruitment variability in young-of-the-year (YOY) striped bass Morone saxatilis from Chesapeake Bay were investigated based on (1) surveys from 2001 to 2003 to document spatio-temporal variability in abundance of larval striped bass, zooplankton prey, and feeding success of larvae; (2) a synthetic analysis (1996, 1998, 1999, 2001 to 2003) to describe how environmental factors and prey affect recruitment success; and (3) a 10 yr analysis (1993 to 2002) of inter-annual differences in spatial and temporal patterns of copepods and cladocera eaten by striped bass larvae. Striped bass YOY recruitment levels varied >11-fold in the 6 years examined. In those years, mean daily freshwater flows from the Susquehanna River to the bay in March and April varied > 2-fold and controlled distribution and apparent survival of striped bass larvae. Strong recruitments of YOY striped bass were associated with matches in space and time of larval striped bass and high concentrations of zooplankton prey, especially the copepod Eurytemora affinis and cladoceran Bosmina longirostris. The strongest year classes (1996, 2003) were produced in years of high freshwater flow, characterized by a high abundance of feeding-stage larvae and a spatio-temporal match between peak abundance of larvae and zooplankton prey. Enhanced feeding opportunities were most pronounced in high freshwater-flow years (1996, 1998, 2003), when larvae and zooplankton prey were strongly associated with, and apparently retained near, the estuarine turbidity maximum. First-feeding larvae fed more successfully in a high-flow year (2003; prey incidence 91%) than in a drier year (2001; prey incidence 35%). A regression model that may have forecasting potential was developed to describe recruitment of YOY striped bass for the years from 1985 to 2006. The model includes spring freshwater flow and air temperatures to predict age-0 striped bass recruitment strength (R 2 = 0.65). Flow and temperature control environmental and hydrographic conditions that strongly influence spatio-temporal overlap of larval striped bass and zooplankton. The model provided accurate recruitment forecasts for 2007 and 2009, but was less successful in 2008, a year of exceptionally low recruitment. KEY WORDS: Chesapeake Bay · Striped bass · Recruitment variability · Larval fish · Zooplankton · Trophodynamics · Biophysical interactions Resale or republication not permitted without written consent of the publisherMar Ecol Prog Ser 409: [213][214][215][216][217][218][219][220][221][222][223][224][225][226][227][228] 2010 leading to higher larval growth rates and increased larval survival (Houde 2008).Spatial variability in the prey available to larvae, while not explicitly formalized in critical period and match-mismatch hypotheses, is recognized as a determinant of growth and survival. Feeding conditions of larval fish across mesoscale (>1 to 100 km) gradients in prey concentrations are often attributable to prevailing circulation patterns, frontal features, and interacting spa...

Abundance of age-0 striped bass ( Morone saxatilis ) exhibits 50-fold variability in Chesapeake Bay. Processes that act to reduce and thus regulate this variability were investigated. The potential for density-dependent regulation of growth and mortality in the early juvenile stage and its causes were investigated. Data from multiple seine and trawl surveys in upper Chesapeake Bay and tributaries were analyzed to construct growth and mortality indices having a high degree of spatial and temporal resolution. Age-0 mean lengths in September were inversely related to density, ranging from 67.8 mm in 1994, when mean density was 0.036·m–2, to 104.5 mm in 1992, when mean density was 0.003·m–2. Except for the Potomac River, evidence for density-dependent growth was consistent across subpopulations. Bioenergetics modeling indicated that prey consumption was limiting except in low-abundance years. Mortality increased with respect to abundance and also was density-dependent. The significant interaction between age-0 juvenile length in September and subsequent winter temperature on mortality indicated that density-dependent growth leads to size-selective overwinter mortality. A statistical model including age-0 abundances, age-0 lengths, and winter temperature explained a substantial fraction of variability and the mechanisms for regulation of striped bass recruitment.

This review provides an examination of the consequences of climate change in the coming century to saltwater sport fishing. We emphasized recreational fisheries in the U.S. Atlantic, but draw from the broader national and international literature where appropriate. Three themes were addressed: (1) climate change in the U.S. Atlantic, with a focus on increases in temperature, precipitation, sea level, the frequency and intensity of storms, and changes in ocean circulation;(2) the response of marine and estuarine fishes to climate change on an individual, population, and community-level; and (3) the response of marine and estuarine recreational fisheries to climate change. In addition, we provide strategies for the future of fisheries assessment and management in response to climate change.