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EFFECTS OF THE DREDGING
OF THE PACKERY
CHANNEL
ON COMMERCIALLY IMPORTANT NEKTON

In the Gulf of Mexico, the vast majority of commercially important species are estuarine-dependent with larvae migrating through tidal inlets to reach their “nursery” grounds. Access to high quality habitats in estuarine areas via tidal inlets is critical for reproduction, growth, survival, and sustainability of these populations. Packery Channel, a natural tidal inlet, has been closed since the 1930’s due to sedimentation. The US Army Corps of Engineers recently dredged and permanently reopened this inlet to allow water exchange from the Gulf of Mexico into the Laguna Madre near Corpus Christi Bay, Texas. The purpose of this study was to assess the impact of this new inlet on estuarine nekton. I found distinct differences in nekton mean densities post-channel opening. These results suggest that the Packery Channel may have important implications to fisheries and other recruiting nekton along the Texas coast by allowing increased access to the extensive seagrass meadows ofthe Laguna Madre. Otolith microstructure analysis of newly settled red drum Sciaenops ocellatus from Aransas Bay, Corpus Christi Bay, and the upper Laguna Madre indicated that there are similar growth rates among all three bays and that habitats adjacent to Packery Channel function as nursery habitats for red drum.Differences in community assemblages were also found after Packery Channel was open. Diversity was significantly higher post-opening, although it is not clear if this was due to the inlet or other environmental variables. At the conclusion of this study, Packery Channel showed substantial flow, but was still under construction. Once the channel is fully dredged flow will increase likely resulting in higher recruitment potential for nekton that rely on these tidal inlets for access to estuarine nursery habitats. |