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The article presents a study on the reef fish community structure off the coast of New Providence Island in The Bahamas. It discusses details of the findings based on a resurvey of the community in 2006 and comparisons with baseline data from 1955 to 1973 to determine if there had been changes in diversity over the 50-year period. It highlights the importance of monitoring the areas, particularly the prevalence of the invasive lionfish, Pterois volitans.

Mark-recapture experiments were conducted in the tidal Nanticoke River (Chesapeake Bay) to determine how the salt front retains striped bass larvae and controls nursery production. During two spring spawning seasons, 25.1 million hatchery-produced, first-feeding larvae (5-12 days post-hatch) were released with chemically marked otoliths at selected locations and times. Surveys tracked the spatial and demographic fates of released and naturally spawned larvae. Released larvae dispersed rapidly within the freshwater tidal portion of the estuary and were retained above the salt front. Their distributions overlapped with natural larvae. Growth and mortality rates did not differ with respect to release location, but did vary with day of release, influenced by storm events and seasonal changes in temperature. In 1993, a group released during a storm event did not yield any recaptured larvae. Zooplankton concentrations in both years were likely sufficient for successful larval feeding. In spring 1993, a season of relatively high freshwater flow, nursery volume was 2.1-fold larger and juvenile production from larval releases was fourfold higher than in 1992. We propose that increased nursery volume reduces variance in water quality, enhances retention of larvae within the nursery, thus increasing production of larval striped bass. [ABSTRACT FROM AUTHOR]