Determination of food sources for benthic invertebrates and brook trout Salvelinus fontinalis in Canadian Boreal Shield lakes using stable isotope analysis

Abstract Kajikia audax, Thunnus albacares, Katsuwonus pelamis, and Auxis spp. occupy high and middle-level trophic positions in the food web. They represent important sources for fisheries in Ecuador. Despite their ecological and economic importance, studies on pelagic species in Ecuador are scarce. This study uses stable isotope analysis to assess the trophic ecology of these species, and to determine the contribution of prey to the predator tissue. Isotope data was used to test the hypothesis that medium-sized pelagic fish species have higher δ15N values than those of the prey they consumed, and that there is no overlap between their δ13C and δ15N values. Results showed higher δ15N values for K. audax, followed by T. albacares, Auxis spp. and K. pelamis, which indicates that the highest position in this food web is occupied by K. audax. The stable isotope Bayesian ellipses demonstrated that on a long time-scale, these species do not compete for food sources. Moreover, δ15N values were different between species and they decreased with a decrease in predator size.

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Determination of geographic origin of caffeine by stable isotope analysis

Analytical Chemistry ◽

10.1021/ac00240a057 ◽

1982 ◽

Vol 54 (3) ◽

pp. 590-592 ◽

Cited By ~ 20

Author(s):

John. Dunbar ◽

A. T. Wilson

Keyword(s):

Stable Isotope ◽

Stable Isotope Analysis ◽

Isotope Analysis ◽

Geographic Origin

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Nitrate-Nitrogen Concentration in Groundwater of Kumamoto Urban Area and Determination of Its Contributors Using Geographical Information System and Nitrogen Stable Isotope Analysis

Journal of Japan Society on Water Environment ◽

10.2965/jswe.34.1 ◽

2010 ◽

Vol 34 (1) ◽

pp. 1-9 ◽

Cited By ~ 3

Author(s):

Kazuo TOMIIE ◽

Naotaka ITOMITSU ◽

Kenji MATSUYAMA ◽

Ryuji KAKIMOTO ◽

Yasunori KAWAGOSHI

Keyword(s):

Information System ◽

Stable Isotope ◽

Urban Area ◽

Stable Isotope Analysis ◽

Nitrate Nitrogen ◽

Nitrogen Concentration ◽

Isotope Analysis ◽

Geographical Information ◽

Nitrogen Stable Isotope

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Food sources of the Manila clam Ruditapes philippinarum in intertidal areas: evidence from stable isotope analysis

Chinese Journal of Oceanology and Limnology ◽

10.1007/s00343-013-2191-2 ◽

2013 ◽

Vol 31 (4) ◽

pp. 782-788 ◽

Cited By ~ 1

Author(s):

Liqiang Zhao ◽

Xiwu Yan ◽

Feng Yang

Keyword(s):

Stable Isotope ◽

Stable Isotope Analysis ◽

Isotope Analysis ◽

Ruditapes Philippinarum ◽

Manila Clam ◽

Food Sources

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Seasonal fluctuation in food sources of herbivorous gastropods in a subtropical seagrass bed estimated by stable isotope analysis

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315418001108 ◽

2018 ◽

Vol 99 (5) ◽

pp. 1119-1125

Author(s):

Kenta Nakamoto ◽

Jun Hayakawa ◽

Tomohiko Kawamura ◽

Naoya Ohtsuchi ◽

Hideaki Yamada ◽

...

Keyword(s):

Stable Isotope ◽

Seasonal Change ◽

Stable Isotope Analysis ◽

Isotope Analysis ◽

Seasonal Fluctuation ◽

Food Sources ◽

Seagrass Bed ◽

Gastropod Species ◽

Total Contribution ◽

Herbivorous Gastropods

AbstractVarious herbivorous invertebrates in seagrass beds are considered to be generalists in food use and their diets may temporally fluctuate according to the availability of food sources. We assessed whether food sources of herbivorous gastropods vary in a subtropical seagrass bed in Nagura Bay, Ishigaki Island, where coexisting seaweeds grow densely in spring but minimally in summer. Abundant gastropods and their possible food sources were collected in spring and summer of 2013 and 2015, and their stable carbon and nitrogen isotope ratios were measured. Between the two seasons, each possible food source had similar isotopic values, but all the herbivorous gastropod species in summer were more enriched in 13C than the gastropod samples in spring. The mixing models in SIAR (Stable Isotope Analysis in R) showed that the total contribution rates of seaweeds, i.e. rhodophytes, phaeophytes and chlorophytes, for all herbivorous gastropod species decreased from spring to summer; in contrast, the contribution rate of seagrasses increased. Linear Mixed Models showed that the seasonal variation in δ13C of the herbivorous gastropods was larger than that of the possible food sources, adding further evidence to the seasonal change in food sources of the herbivorous gastropods. This seasonal change in food use appears to correspond to the change in seaweed biomass, suggesting that herbivorous gastropods flexibly change their diets depending on food availability.

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Gut content and stable isotope analysis of tadpoles in floodplain wetlands

Australian Journal of Zoology ◽

10.1071/zo18043 ◽

2018 ◽

Vol 66 (4) ◽

pp. 261 ◽

Cited By ~ 1

Author(s):

J. F. Ocock ◽

K. J. Brandis ◽

B. J. Wolfenden ◽

K. M. Jenkins ◽

S. Wassens

Keyword(s):

Stable Isotope ◽

Stable Isotope Analysis ◽

Management Strategies ◽

Isotope Analysis ◽

Food Sources ◽

Gut Contents ◽

Floodplain Wetlands ◽

Gut Content ◽

Larval Amphibians ◽

Aquatic Food

Larval amphibians (tadpoles) are an important link in aquatic food webs, as they can be highly abundant consumers and prey for a wide variety of predators. Most tadpoles are considered omnivores, predominately grazing on algae, detritus and macrophytes, though recent work has identified greater plasticity and breadth in diet than previously considered. We used gut content and stable isotope analysis (SIA) in a baseline study to determine the important dietary items (ingested material) and food sources (assimilated material) for tadpoles of two abundant generalist frog species in regulated floodplain wetlands of the Murrumbidgee River, south-east Australia. We identified a wide variety of dietary items in the gut contents, including whole microcrustaceans, filamentous algae and macrophytes. The composition of several ingested food items was correlated with their availability in each wetland. However, SIA identified biofilm as the food source most consistently assimilated across several wetlands, though microcrustaceans and algae contributed when abundant. Biofilm is likely the most important basal food item for tadpoles in floodplain wetlands because it is ubiquitous and has a high nutritional quality. Identifying important food sources is a crucial step towards developing management strategies for promoting tadpole recruitment in regulated wetlands.

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