Fins are relevant non-lethal surrogates for muscle to measure stable isotopes in amphibians

Stable isotope analyses (SIA) are now widely used in ecology research to quantify the trophic implications of a large range of ecological processes. Non-destructive sampling methods have been successfully developed for most vertebrates, but the validation of such methods is missing in amphibians. Filling this methodological gap is critical to reduce the significant lack of knowledge on the trophic ecology of this imperilled group. The relevance of tail fin as a surrogate for muscle, a tissue routinely used for SIA, was assessed in four amphibian species, including tadpoles and adult newts, by (1) testing the link between the isotope ratios of carbon and nitrogen in fin and muscle, and addressing the additional practical issues of (2) the effects of a topical anaesthetic on isotope ratios, and (3) the minimum quantities of fin needed for SIA to limit the severity of sampling. The isotope ratios were highly correlated between the two tissues in all four species. Equations were provided to predict muscle estimates from fin values for each species separately and grouped by their taxonomic order (anurans or urodeles), which represent a valuable solution for any other species. Topical anaesthetics had little influence on isotope ratios, and the surface of tail fin needed for SIA was small. We conclude that the tail fin of amphibians can be used as a non-lethal surrogate for muscle in SIA, and this offers promising prospects for research on the trophic ecology of amphibians, and potentially on their conservation.

Download Full-text

Stable isotopes of carbon and nitrogen in the study of avian and mammalian trophic ecology

Canadian Journal of Zoology ◽

10.1139/z99-165 ◽

2000 ◽

Vol 78 (1) ◽

pp. 1-27 ◽

Cited By ~ 727

Author(s):

Jeffrey F Kelly

Keyword(s):

Stable Isotopes ◽

Stable Isotope ◽

Carbon Isotope ◽

Isotope Ratio ◽

Trophic Ecology ◽

Nitrogen Isotope ◽

Isotope Ratios ◽

Food Chains ◽

Stable Isotope Ratios ◽

Carbon And Nitrogen

Differential fractionation of stable isotopes of carbon during photosynthesis causes C4 plants and C3 plants to have distinct carbon-isotope signatures. In addition, marine C3 plants have stable-isotope ratios of carbon that are intermediate between C4 and terrestrial C3 plants. The direct incorporation of the carbon-isotope ratio (13C/12C) of plants into consumers' tissues makes this ratio useful in studies of animal ecology. The heavy isotope of nitrogen (15N) is preferentially incorporated into the tissues of the consumer from the diet, which results in a systematic enrichment in nitrogen-isotope ratio (15N/14N) with each trophic level. Consequently, stable isotopes of nitrogen have been used primarily to assess position in food chains. The literature pertaining to the use of stable isotopes of carbon and nitrogen in animal trophic ecology was reviewed. Data from 102 studies that reported stable-isotope ratios of carbon and (or) nitrogen of wild birds and (or) mammals were compiled and analyzed relative to diet, latitude, body size, and habitat moisture. These analyses supported the predicted relationships among trophic groups. Carbon-isotope ratios differed among species that relied on C3, C4, and marine food chains. Likewise, nitrogen-isotope ratios were enriched in terrestrial carnivorous mammals relative to terrestrial herbivorous mammals. Also, marine carnivores that ate vertebrates had nitrogen-isotope ratios that were enriched over the ratios of those that ate invertebrates. Data from the literature also indicated that (i) the carbon-isotope ratio of carnivore bone collagen was inversely related to latitude, which was likely the result of an inverse relationship between the proportion of carbon in the food chain that was fixed by C4 plants and latitude; (ii) seabirds and marine mammals from northern oceans had higher nitrogen-isotope ratios than those from southern oceans; (iii) the nitrogen-isotope ratios of terrestrial mammals that used xeric habitats were higher than the ratios of those that used mesic habitats, indicating that water stress can have important effects on the nitrogen-isotope ratio; (iv) there was no relationship between body mass and nitrogen-isotope ratio for either bone collagen or muscle of carnivores; and (v) there was linear covariation between stable-isotope ratios of carbon and nitrogen in marine food chains (but not in terrestrial C3 or C4 food chains), which is likely a product of increases in carbon-isotope ratio with trophic level in marine food chains. Differences in stable-isotope composition among trophic groups were detected despite variation attributable to geographic location, climate, and analytical techniques, indicating that these effects are large and pervasive. Consequently, as knowledge of the distribution of stable isotopes of carbon and nitrogen increases, they will probably become an increasingly important tool in the study of avian and mammalian trophic ecology.

Download Full-text

Geographical variations in the trophic ecology of Japanese anchovy, Engraulis japonicus, inferred from carbon and nitrogen stable isotope ratios

Marine Biology ◽

10.1007/s00227-008-0949-4 ◽

2008 ◽

Vol 154 (3) ◽

pp. 557-568 ◽

Cited By ~ 32

Author(s):

Hiroshige Tanaka ◽

Akinori Takasuka ◽

Ichiro Aoki ◽

Seiji Ohshimo

Keyword(s):

Stable Isotope ◽

Trophic Ecology ◽

Isotope Ratios ◽

Stable Isotope Ratios ◽

Japanese Anchovy ◽

Nitrogen Stable Isotope ◽

Carbon And Nitrogen ◽

Engraulis Japonicus ◽

Geographical Variations

Download Full-text

Lead isotope ratios in 16th century copperware traded to North America: the Swedish connection

Canadian Journal of Physics ◽

10.1139/cjp-2017-0117 ◽

2018 ◽

Vol 96 (4) ◽

pp. 438-444

Author(s):

R.M. Farquhar ◽

R.G.V. Hancock ◽

L.A. Pavlish

Keyword(s):

Lead Isotope ◽

Pure Copper ◽

Isotope Ratios ◽

16Th Century ◽

Eastern Canada ◽

Central European ◽

Small Set ◽

Highly Correlated ◽

End Members ◽

Isotope Analyses

Isotope analyses have been made on the trace amounts of lead in a small set of late 16th century pure copper trade kettles and kettle debris from Indigenous sites in eastern Canada. The isotope ratios are highly correlated. We interpret these correlations as the mixing of copper from Precambrian Swedish ores with metal from one or more of the Palaeozoic deposits occurring in central Europe and the British Isles. The data enable us to identify samples of pure Swedish copper, metal consisting of mixtures of Swedish and central European – British copper, and with less certainty, samples derived entirely from the latter deposits. Although most of the trace element concentrations in the coppers are quite variable, it appears that nickel values may be less so (∼100 ppm in pure Swedish samples, and ∼1100 ppm in the central European – British sources). Based on these values, two-component mixing relations provide estimates of the fractions of Swedish end members in mixed samples. These results suggest that more than half of the copper used in forming the kettles originated in Sweden.

Download Full-text

TRANSFER EFFICIENCY FROM PRIMARY PRODUCERS TO RUDITAPES PHILIPPINARUM ON AN INTERTIDAL FLAT IN HIROSHIMA BAY, JAPAN

Proceedings of International Conference "Managinag risks to coastal regions and communities in a changinag world" (EMECS'11 - SeaCoasts XXVI) ◽

10.31519/conferencearticle_5b1b93b4af8c32.73166623 ◽

2017 ◽

Author(s):

Sosuke Otani ◽

Akira Umehara ◽

Haruka Miyagawa ◽

...

Keyword(s):

Stable Isotope ◽

Secondary Production ◽

Isotope Ratios ◽

Ruditapes Philippinarum ◽

Transfer Efficiency ◽

Food Sources ◽

Stable Isotope Ratios ◽

Primary Producers ◽

Nitrogen Stable Isotope ◽

Carbon And Nitrogen

Fish yields of Ruditapes philippinarum have been decreased and the resources have not yet recovered. It needs to clarify food sources of R. philippinarum, and relationship between primary and secondary production of it. The purpose on this study is to reveal transfer efficiency from primary producers to R. philippinarum and food sources of R. philippinarum. The field investigation was carried out to quantify biomass of R. philippinarum and primary producers on intertidal sand flat at Zigozen beach in Hiroshima Bay, Japan. In particular, photosynthetic rates of primary producers such as Zostera marina, Ulva sp. and microphytobenthos were determined in laboratory experiments. The carbon and nitrogen stable isotope ratios for R. philippinarum and 8 potential food sources (microphytobenthos, MPOM etc) growing in the tidal flat were also measured. In summer 2015, the primary productions of Z. marina, Ulva sp. and microphytobenthos were estimated to be 70.4 kgC/day, 43.4 kgC/day and 2.2 kgC/day, respectively. Secondary production of R. philippinarum was 0.4 kgC/day. Contribution of microphytobenthos to R. philippinarum as food source was 56-76% on the basis of those carbon and nitrogen stable isotope ratios. Transfer efficiency from microphytobenthos to R. philippinarum was estimated to be 10-14%. It was suggested that microphytobenthos might sustain the high secondary production of R. philippinarum, though the primary production of microphytobenthos was about 1/10 compared to other algae.

Download Full-text