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11	Assessing the Responses of Adult, Juvenile, and Larval Fish Assemblages to the Closure of the Mississippi River Gulf Outlet, an Artificial Tidal Pass in Southeastern Louisiana Cope, Rebecca Weatherall 20 December 2013 (has links) The creation of the Mississippi River Gulf Outlet (MRGO) in 1963 by the U.S. Army Corps of Engineers (USACE) represents one of the most catastrophic, anthropogenic stressors ever to impact the Lake Pontchartrain estuary in southeastern Louisiana, USA. The artificial tidal pass provided a direct route from the Gulf of Mexico to New Orleans. It allowed for high saline waters to enter Lake Pontchartrain, resulting in detrimental changes to the biotic community of the Lake and surrounding wetland areas. In July 2009, the USACE closed the MRGO in hopes of restoring natural ecosystems. This study assesses changes in the adult, juvenile, and larval fish assemblages in the Lake from data taken before and after the closure. Water quality data were also examined for shifts related to the MRGO closure. Significant decreases in salinity were found following the closure, however no significant differences were found in adult or larval fish assemblages. Mississippi River Gulf Outlet (MRGO) Lake Pontchartrain tidal pass fish assemblages larval salinity Biology Ecology and Evolutionary Biology Life Sciences Marine Biology Terrestrial and Aquatic Ecology
12	Abundance and Distribution of Early Life Stage Blue Crabs (Callinectes sapidus) in Lake Pontchartrain Lyncker, Lissa 07 August 2008 (has links) I conducted a 12-month study of near-shore habitats in Lake Pontchartrain to assess spatiotemporal variation in the abundance of early life stage blue crabs (Callinectes sapidus). Collections were made using a 1 m2 throw trap and data showed that C. sapidus numbers varied over time and among sites. Two recruitment events occurred during the study. During the first recruitment in May-June, C. sapidus entered Lake Pontchartrain via the Inner Harbor Navigational Canal. In September-October, C. sapidus entered the Lake Pontchartrain via the Rigolets and Chef passes. My data suggest that C. sapidus utilize water circulation within the Lake Pontchartrain as a means of transportation throughout the estuary. MODerate-resolution Imaging Spectroradiometer (MODIS) 250 m data were analyzed to gain a large-scale view of suspended sediments patterns within Lake Pontchartrain and quantify water movement. Field sampling along with remote sensing proved to be beneficial when assessing estuarine-wide C. sapidus post-larval dispersal processes. Callinectes sapidus blue crab crab migration crab transport Callinectes sapidus transport nursery habitat dispersal post-larval dispersal post-settlement dispersal recruitment SAV Lake Pontchartrain mass water movement remote sensing MODIS 250 m data MODIS 250 m satellite images estuarine dependent species suspended sediment

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Assessing the Responses of Adult, Juvenile, and Larval Fish Assemblages to the Closure of the Mississippi River Gulf Outlet, an Artificial Tidal Pass in Southeastern Louisiana

Abundance and Distribution of Early Life Stage Blue Crabs (Callinectes sapidus) in Lake Pontchartrain