Stable isotopes are increasingly used to infer sources of nutrient enrichment and trophic linkages in coastal marine systems, although the utility of these tools often depends upon a predictable expression of δ15N and δ13C signatures by primary producers. Accordingly, we examined how tissue δ15N and δ13C values change in the common coastal marine alga Ulva pertusa Kjellman under contrasting lig...

We present the first measurements of nitrogen isotopic composition (δ15N) in suspended particulate matter (SPM) of the surface Bay of Bengal (BOB) at 24 different locations during pre(April–May 2003) and post(September– October 2002) monsoon seasons. The δ15N values of particulate organic nitrogen (PON) in surface suspended matter of coastal and northern open BOB show mixing between continental...

We examine here the carbon and nitrogen isotopic compositions of bulk soils (8 topsoil and 7 subsoils, including two soil profiles) and five different plant parts of 79 C3 plants from two main functional groups: herbs and shrubs/subshrubs, from 18 different locations in grasslands of southern Yukon Territory, Canada (eastern shoreline of Kluane Lake and Whitehorse area). The Kluane Lake region ...

Twenty seven trace elements (Li, Mg, Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, In, Sn, Sb, Cs, Ba, Tl, Hg, Pb, Bi) and stable isotope ratios (δ13C and δ15N) were measured in deep sea organisms from OffSanninn and Off-Hokuriku, Japan to evaluate the trophic transfer of these elements. Concentrations of Al, Fe, In, Sb and Ba were positively correlated with δ15N values suggest...

Consumer-diet discrimination factors (Δ15N and Δ13C) are often applied without corroboration from laboratory experiments. Deviations in Δ15N and Δ13C that may occur from different diet types were quantified by raising 120 sea urchins Lytechinus variegatus in laboratory tanks on 3 different diets: seagrass Thalassia testudinum, red foliose macroalgae (Grauteloupia sp. and Palmaria palmata) and a...

Nitrogen isotope analysis is a common technique for investigating dietary behaviour in modern and archaeological populations. One of its primary uses is to provide trophic level information. This application is possible because of a ∼3‰ enrichment in 15N along each step in the food chain, resulting in carnivores having higher δ15N values than herbivores, which in turn have higher δ15N values th...

A temporal change in stable isotope (δ15N) distributions in North Sea harbour porpoises Phocoena phocoena (L.) was documented by analysing stable isotope abundances in bone collagen from 88 skeletons of harbour porpoises stranded in the period between 1848 and 2002 along the southern North Sea coast. Porpoises collected after ~1960 had significantly lower δ15N than porpoises collected earlier. ...

We compared effects of different sample preparation techniques on the stable carbon and nitrogen isotope values of fish muscle, whole crustaceans and particulate organic matter (POM). Comparisons were also made to untreated (i.e. dried and homogenised) samples. Relatively carbonate-rich samples treated with weak acid (0.1 N HCl), either by quickly wetting or acid dampening, were on average 1.3‰...

Trophic interactions between organisms are the main drivers of ecosystem dynamics, but scant dietary information is available for wide-ranging predators during migration. We investigated feeding habits of a key consumer of the Southern Ocean, the southern elephant seal Miroungia leonina, by comparing its blood δ13C and δ15N values with those of various marine organisms, including crustaceans, s...

Scat is frequently used to study animal diets because it is easy to find and collect, but one concern is that gross fecal analysis (GFA) techniques exaggerate the importance of small-bodied prey to mammalian mesopredator diets. To capitalize on the benefits of scat, we suggest the analysis of scat carbon and nitrogen isotope values (δ13C and δ15N). This technique offers researchers a non-invasi...