The retention of fish larvae in estuaries: among-tide variability at Beaufort Inlet, North Carolina, USA

Abstract

Sixty-eight tides were sampled consecutively to study the retention of fish larvae transported into estuaries. The experiment was conducted at Beaufort Inlet, North Carolina, USA, in March 1996. The inlet is primarily tide-driven and meteorological forcing has a minor influence. Four species of winter-spawning fish were abundant in the samples: Atlantic menhaden, Brevoortia tyrannus; Atlantic croaker, Micropogonias undulatus; spot, Leiostomus xanthurus; and pinfish, Lagodon rhomboides. Across-shore winds significantly affected flow and physico-chemical characteristics of the water. Across-shore winds also positively influenced the larval retention provided larvae did not present a clear tidal rhythm of vertical migration within the water column and that winds pushed in the water during flood tides. The retention of larvae migrating vertically in respect to the direction of the flow was independent of meteorological forcing of the water.