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This release is for data on Zinc concentrations and isotopic signatures of an aquatic insect (mayfly, Baetis tricaudatus). Mayflies were exposed to an aqueous zinc concentration gradient in a laboratory experiment. Zinc concentrations were measured in water, algae (mayfly food), and different mayfly lifestages. Natural abundances of carbon and nitrogen isotopes were also measured in different life stages. This data set includes on Zinc data. Isotope data are provided in a separate file. The abstract for a journal article explaining the results of the experiment follows below: Insect metamorphosis often results in substantial chemical changes that can fractionate isotopes and alter contaminant concentrations. We...
This release is for data on Zinc concentrations and isotopic signatures of an aquatic insect (mayfly, Baetis tricaudatus). Mayflies were exposed to an aqueous zinc concentration gradient in a laboratory experiment. Zinc concentrations were measured in water, algae (mayfly food), and different mayfly lifestages. Natural abundances of carbon and nitrogen isotopes were also measured in different life stages. This data set includes on Zinc data. Isotope data are provided in a separate file. The abstract for a journal article explaining the results of the experiment follows below: Insect metamorphosis often results in substantial chemical changes that can fractionate isotopes and alter contaminant concentrations. We...
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Despite being one of the most prevalent forms of consumerism in ecological communities, parasitism has largely been excluded from food-web models. Stable isotope analysis of consumers and their diets has been widely used in the study of food-webs for decades. However, the amount of information regarding parasite stable isotope ecology is limited, restricting the ability of ecologists to use stable isotope analysis to study parasites in food-webs. This study took advantage of distinct differences in the feeding ecology and trophic position of different species of fish known to host the same common micropredatory gnathiid isopod, to study the effects of host stable isotope ecology on that of the associated micropredator....
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Chemosynthetic environments support distinct benthic communities capable of utilizing reduced chemical compounds for nutrition. Hundreds of methane seeps have been documented along the U.S. Atlantic margin (USAM), and detailed investigations at a few seeps have revealed distinct environments containing mussels, microbial mats, authigenic carbonates, and soft sediments. The dominant mussel Bathymodiolus childressi contains methanotrophic endosymbionts but is also capable of filter feeding. We used SIA (δ13C, δ 5N, and δ34S) and an isotope mixing model (MixSIAR) to estimate resource contribution to B. childressi and characterize food webs at two seep sites (Baltimore Seep: 400 m and Norfolk Seep: 1500 m depths) along...
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The primary objective of this study was to assess deepsea food web structure and trophic niches in Baltimore and Norfolk canyons, the adjacent slopes, and chemosynthetic seeps along the mid-Atlantic margin using stable isotope analyses (SIA) and isotope niche width analysis. We hypothesized that the isotopic compositions of canyon versus slope fauna would be distinct, given differences in the physics and chemistry of the canyons and slopes and resulting quality and quantity of the organic matter available to the benthos. These differences should be evident across taxa and among and within feeding groups. We also used SIA to estimate trophic positions of invertebrates and fishes and to examine changes in trophic...
Insect metamorphosis often results in substantial chemical changes that can fractionate isotopes and alter contaminant concentrations. We exposed larval mayflies (Baetis tricaudatus) to an aqueous zinc gradient (3-340 µg Zn/l) and measured the change in zinc tissue concentrations at different stages of metamorphosis. We also measured changes in stable isotopes (δ15N and δ13C) in unexposed B. tricaudatus. Zinc concentrations in larvae were positively related to aqueous zinc, increasing 9-fold across the exposure gradient. Zinc concentrations in adults were also positively related to aqueous concentrations, but were 7-fold lower than larvae. However, this relationship varied according to adult substage (subimago vs...
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This study was initiated to provide baseline data and to determine the utility of stable isotope analysis to evaluate the foraging strategies of an opportunistic reptile predator. Stable isotope ratios of carbon and nitrogen were evaluated from multiple tissues from terrapin populations to determine spatial or temporal variations in resource use within mangrove habitats in Southern Florida. We sampled Diamondback terrapin (Malaclemys terrapin) and potential resources within mainland and island habitats, and evaluated their δ13C and δ15N values. We fit linear regression models to determine the best predictors of isotopic values for both terrapins and their prey, and SIBER analysis to examine terrapin isotopic niche...
This dataset includes information from multiple taxa collected from four main reaches in the Upper Mississippi River Basin, including La Grange reach of Illinois River, Pool 2 of Mississippi River, Pool 19 of Mississippi River, and the St. Croix River. Taxa include hydropsychid caddisflies, chironomids, hexagenia mayflies, threeridge mussels, mapleleaf mussels, Wabash pigtoe mussels, bigmouth buffalo, gizzard shad, and bluegill. Seston samples were also collected, in addition to water samples for identifying and enumerating phytoplankton species. Fatty acids, lipids, and stable isotopes were quantified for the aforementioned taxa. Water quality data were recorded at the time of sample collection and discharge data...


    map background search result map search result map Food-web structure of canyon and slope associated fauna revealed by stable isotopes Stable isotope ratios of carbon and nitrogen from diamondback terrapins and resources within Southern Everglades and Key West National Wildlife Refuge, sampled 2012-2013 Host feeding ecology and trophic position significantly influence isotopic discrimination between a generalist ectoparasite and its hosts: implications for parasite-host trophic studies Stable isotopic insights into Bathymodiolus childressi at two seeps in the U.S. Atlantic margin Host feeding ecology and trophic position significantly influence isotopic discrimination between a generalist ectoparasite and its hosts: implications for parasite-host trophic studies Stable isotopic insights into Bathymodiolus childressi at two seeps in the U.S. Atlantic margin Stable isotope ratios of carbon and nitrogen from diamondback terrapins and resources within Southern Everglades and Key West National Wildlife Refuge, sampled 2012-2013 Food-web structure of canyon and slope associated fauna revealed by stable isotopes