Seasonal variation in morphotype composition of pelagic Sargassum influx events is linked to oceanic origin.

The recent proliferation of pelagic Sargassum spp. in the Tropical Atlantic causes major ecological and socioeconomic impacts to the wider Caribbean when it washes ashore, with regional fisheries and tourism industries particularly affected. The Caribbean influxes have been tracked to a new bloom region known as the North Equatorial Recirculation Region (NERR) encompassing the area between the South Equatorial Current and the North Equatorial Counter Current and extending from Africa to South America.

Environmental extremes drive population structure at the northern range limit of Atlantic salmon in North America.

Conservation of exploited species requires an understanding of both genetic diversity and the dominant structuring forces, particularly near range limits, where climatic variation can drive rapid expansions or contractions of geographic range. Here, we examine population structure and landscape associations in Atlantic salmon (Salmo salar) across a heterogeneous landscape near the northern range limit in Labrador, Canada. Analysis of two amplicon-based data sets containing 101 microsatellites and 376 single nucleotide polymorphisms (SNPs) from 35 locations revealed clear differentiation between populations spawning in rivers flowing into a large marine embayment (Lake Melville) compared to coastal populations.

Seasonal hypoxia regulates macrobenthic function and structure in the Mississippi Bight.

Hypoxic conditions are escalating to the east of the Mississippi River within the Mississippi Bight. The objective of this study was to examine changes in macrobenthic function and structure relative to seasonal hypoxia over a 3.5year period at the 10m (Site 6) and 20m (Site 8) isobaths within the Mississippi Bight.

Variability in the characterization of total coliforms, fecal coliforms and Escherichia coli in recreational water supplies of north Mississippi, USA.

The fecal coliform, Escherichia coli, is a historical organism for the detection of fecal pollution in water supplies. The presence of E. coli indicates a potential contamination of the water supply by other more hazardous human pathogens.

Grass shrimp (Palaemonetes spp.) play a pivotal trophic role in enhancing Ruppia maritima.

Coupled trophic-engineer interactions are potentially important for maintaining habitat function and ecosystem services. As ephemeral submerged aquatic vegetation (SAV), Ruppia maritima has a short well-defined growth-senescence cycle and should benefit from any ecological interaction that enhances its physical condition and longevity. Grass shrimp (Palaemonetes spp.