Filters: Tags: marine biology (X)178 results (227ms)
Predator biomass, prey density, and species composition effects on group size in recruit coral reef fishes
Group incidence and size are described for recruit parrotfishes, wrasses, and damselfishes on Hawaiian reefs over 3 years (2006–2008) at sites spanning the archipelago (20–28°N, 155–177°W). Coral-poor and coral-rich areas were surveyed at sites with both low (Hawaii Island) and high (Midway Atoll) predator densities, facilitating examination of relations among predator and recruit densities, habitat, and group metrics. Predator and recruit densities varied spatially and temporally, with a sixfold range in total recruit densities among years. Group (≥2 recruits) metrics varied with time and tracked predator and recruit densities and the proportion of schooling species. Groups often included heterospecifics whose...
Effects of nutritional history on nitrogen assimilation in congeneric temperate and tropical scleractinian corals
The nutritional history of corals is known to affect metabolic processes such as inorganic nutrient uptake and photosynthesis, but little is known about how it affects assimilation efficiency of ingested prey items or the partitioning of prey nitrogen between the host and symbiont. The temperate scleractinian coral Oculina arbuscula and its tropical congener Oculina diffusa were acclimated to three nutritional regimes (fed twice weekly, starved, starved with an inorganic nutrient supplement), then fed Artemia nauplii labeled with the stable isotope tracer 15N. Fed corals of both species had the lowest assimilation efficiencies (36-51% for O. arbuscula, 38-57% for O. diffusa), but were not statistically different...
Shrimp trawling is common throughout the southeastern and Gulf of Mexico coasts of the USA and is the primary contributor to fisheries discards in these regions. Tens of thousands of nearshore seabirds nest near shrimp trawling grounds in the USA, but to date, there has been no assessment of the relationship between seabirds and shrimp trawlers. We examined the taxonomic composition of bycatch, rate at which seabirds scavenged bycatch, and energy density of discarded bycatch in a nearshore commercial shrimp fishery. Bycatch was primarily comprised of demersal fish that are not typically accessible to the plunge-diving and surface-feeding seabirds that occur in the area. Hence, seabird diets in the region appear...
Assimilation efficiencies and turnover rates of trace elements in marine bivalves: A comparison of oysters, clams and mussels
Assimilation efficiencies (AEs) and physiological turnover-rate constants (k) of six trace elements (Ag, Am, Cd, Co, Se, Zn) in four marine bivalves (Crassostrea virginica Gmelin,Macoma balthica Linnaeus, Mercenaria mercenaria Linnaeus, and Mytilus edulis Linnaeus) were measured in radiotracer-depuration experiments. Egestion rates of unassimilated elements were highest during the first 24 h of depuration and declined thereafter. Significant egestion of unassimilated Co, however, continued for up to 5 d in Macoma balthica,Mercenaria mercenaria and Mytilus edulis. With the exception of the extremely low values for110 mAg, 109Cd, and 65Zn in C. virginica, physiological turnover-rate constants (k) showed no general...
Robustness of supercritical fluid extraction (SFE) in environmental studies: analysis of chlorinated pollutants in tissues from the osprey (pandion haliaetus) and several fish species
Measuring and modelling the dynamic response of remote mountain lake ecosystems to environmental change: An introduction to the MOLAR project
Impact of elevated ammonium on reproduction in two Hawaiian scleractinian corals with different life history patterns
OBIS-USA brings together marine biological occurrence data – recorded observations of identifiable marine species at a known time and place, collected primarily from U.S. Waters or with U.S. funding. Coordinated by the Science Analytics and Synthesis (SAS) Program of the United States Geological Survey (USGS), OBIS-USA, strives to meet national data integration and dissemination needs for marine data about organisms and ecosystems. OBIS-USA is part of an international data sharing network (Ocean Biogeographic Information System, OBIS) coordinated by the Intergovernmental Oceanographic Commission, of UNESCO (United Nations Educational, Science and Cultural Organization) International Oceanographic Data and Information...
The dataset includes multiple file types (CSV, ArcGIS shapefiles, and images), data relates to the elemental analysis of fish otoliths. Otoliths examined in this study were from randomly-sampled individual Tidewater Goby (Eucyclogobius newberryi) and Prickly Sculpin (Cottus asper) from the adult population of Rodeo Lagoon and Rodeo Creek, Marin County, California. The fish were collected in April and August 2016.
Estimation of polychlorinated biphenyl (PCB) levels in livers of the otter (Lutra lutra) from concentrations in scats and fish
Deepwater sampling at a synthetic drilling mud discharge site on the outer continental shelf, northern Gulf of Mexico