The shell composition of planktonic foraminifera used in many paleoreconstructions assumes they are accurately representing conditions at the surface/mixed layer. However, planktonic foraminifera are known to inhabit a depth range that extends below the mixed layer. In the present study, foraminifera were collected at discrete depth intervals using a Multiple Opening and Closing Net Environmental Sensing System (MOCNESS) in either cyclonic or anticyclonic eddies that had contrasting environmental conditions. The foraminifera abundances and distributions were compared to the water depth, temperature, density, and chlorophyll profiles. Nine species were found consistently among all the tows and composed at least 96% of the species found, though a shift in the species abundances and depths occurred between eddies. Species occurred where physical factors were compatible with conditions and feeding opportunities they were adapted to. Three species pink and white Globigerinoides ruber and Globigerinoides sacculifer thrived best when a steep density gradient resulted in a shallower mixed-layer that restricted them under more intense light and allowed them to better exploit their algae symbionts. Globigerina bulloides was found outside its sub-polar habitat because the waters of the cyclones were cool enough (less than 26??C) at the same depths that sufficient chlorophyll was available. Two species Orbulina universa, and Globorotalia menardii were consistently absent in the mixed layer, but tracked deeper chlorophyll concentrations. Three other species were found inconsistently among the tows: Hastigerina pelagica, Globigerinella siphonifera, and Globigerinella calida. H. pelagica probably follows chlorophyll concentrations. G. siphonifera, and G. calida have a preference for deeper waters within the photic zone. The drastic doubling to tripling of the foraminifera abundances in cyclones biases downcore reconstructions of sea surface temperature towards cooler conditions. Also, the shift in species composition between the two eddies indicates that in environments where eddies, upwellings, or rings exist may bias the downcore composition of each species towards cooler conditions. G. sacculifer was found to live primarily in the mixed layer and at least 75% of its downcore individuals are expected to represent conditions there. Researchers should consider the described species distributions to better understand the water column conditions they are reconstructing.

The shell composition of planktonic foraminifera used in many paleoreconstructions assumes they are accurately representing conditions at the surface/mixed layer. However, planktonic foraminifera are known to inhabit a depth range that extends below the mixed layer. In the present study, foraminifera were collected at discrete depth intervals using a Multiple Opening and Closing Net Environmental Sensing System (MOCNESS) in either cyclonic or anticyclonic eddies that had contrasting environmental conditions. The foraminifera abundances and distributions were compared to the water depth, temperature, density, and chlorophyll profiles. Nine species were found consistently among all the tows and composed at least 96% of the species found, though a shift in the species abundances and depths occurred between eddies. Species occurred where physical factors were compatible with conditions and feeding opportunities they were adapted to. Three species pink and white Globigerinoides ruber and Globigerinoides sacculifer thrived best when a steep density gradient resulted in a shallower mixed-layer that restricted them under more intense light and allowed them to better exploit their algae symbionts. Globigerina bulloides was found outside its sub-polar habitat because the waters of the cyclones were cool enough (less than 26??C) at the same depths that sufficient chlorophyll was available. Two species Orbulina universa, and Globorotalia menardii were consistently absent in the mixed layer, but tracked deeper chlorophyll concentrations. Three other species were found inconsistently among the tows: Hastigerina pelagica, Globigerinella siphonifera, and Globigerinella calida. H. pelagica probably follows chlorophyll concentrations. G. siphonifera, and G. calida have a preference for deeper waters within the photic zone. The drastic doubling to tripling of the foraminifera abundances in cyclones biases downcore reconstructions of sea surface temperature towards cooler conditions. Also, the shift in species composition between the two eddies indicates that in environments where eddies, upwellings, or rings exist may bias the downcore composition of each species towards cooler conditions. G. sacculifer was found to live primarily in the mixed layer and at least 75% of its downcore individuals are expected to represent conditions there. Researchers should consider the described species distributions to better understand the water column conditions they are reconstructing.

The assemblage structure, abundance, biomass, and vertical distribution of juvenile reef fishes in the offshore pelagic habitat of the northern Gulf of Mexico are described as part of the NOAA-supported Offshore Nekton Sampling and Analysis Program. The results presented here are from a 3-month, continuous sampling series in 2011 in which discrete depth strata from 0 to 1500 m were sampled using a 10-m2 MOCNESS midwater trawl. This is the first study to examine pelagic juvenile reef fish distributions across the entire oceanic northern Gulf of Mexico seaward of the continental shelf break after the Deepwater Horizon Oil Spill. During this series, 87,407 specimens were collected, of which 838 were reef fishes, representing seven orders, 30 families and 119 species. The faunal composition of pelagic juvenile reef fishes was diverse and well mixed, with no discernable spatial structure with respect to water masses and solar cycle. Seventy-nine percent of the pelagic juvenile reef fishes were collected in the epipelagic and the dominant families were Congridae, Carangidae, Tetraodontidae, and Acanthuridae. Species richness, biomass, and frequency of occurrence of pelagic juvenile reef fishes was greatest between 0-200 m and decreased with depth. Data from the assemblage structure, abundance, biomass, and vertical distribution of pelagic juvenile reef fishes collected from this cruise series will contribute to the lack of knowledge regarding the dispersal dynamics and coastal-connectivity of these fishes in the northern Gulf of Mexico.