Stable Isotopes as Tools in Ecological Research


Stable isotope analysis has proved to be an extremely useful tool in elucidating many ecological problems, with stable isotope ecology comprising the theme of a series of international conferences ( Stable isotopes can be used as biological tracers in the following ways: (1) to identify sources, for instance in determining the identity of basal carbon in a food web; (2) to distinguish sources, for example to determine whether a breeding animal is using local resources or its own reserves, or when an animal migrates/disperses from one location to another and (3) to quantify relative inputs in a system, for example determining the proportions of different prey items to a consumer's diet. When utilised carefully, stable isotope analysis provides some advantages over conventional methods and an additional device for the ecologist.

Key Concepts

  • Stable isotopes are useful tracers of ecological processes.
  • Carbon stable isotopes are useful tools in plant physiology and for tracing carbon sources.
  • Nitrogen stable isotope ratios in animal tissues are useful indicators of trophic level.
  • Combined carbon, nitrogen and sulfur isotope ratios in animal tissues elucidate food webs and trophic niche.
  • Hydrogen and oxygen isotope ratios in animals reflect those of local precipitation.
  • Care is needed when planning isotope food web studies.

Keywords: stable isotopes; ecology; food webs; diet; migration

Figure 1. Schematic marine food web in which δ15N (and δ13C) represent the trophic enrichment factors. See text for further explanation.
Figure 2. Hypothetical diet‐switch experiment. The animal is fed a C3 plant‐based diet for some time, and then switched to a C4 plant‐based diet at time = 0. Analysis of tissue for δ13C is carried out every 10 days. The time for complete carbon turnover is in excess of 100 days.


Adams CE, Bissett N, Newton J and Maitland PS (2008) Alternative migration and host parasitism strategies and their long‐term stability in river lampreys from the River Endrick, Scotland. Journal of Fish Biology 72: 2456–2466.

Bearhop S, Adams CE, Waldron S, Fuller RA and Macleod H (2004) Determining trophic niche width: a novel approach using stable isotope analysis. Journal of Animal Ecology 73: 1007–1012.

Bearhop S, Fiedler W, Furness RW, et al. (2005) Assortative mating as a mechanism for rapid evolution of a migratory divide. Science 310: 502–504.

Bowen GJ and Revenaugh J (2003) Interpolating the isotopic composition of modern meteoric precipitation. Water Resources Research 39: 1299.

Cerling TE, Ayliffe LK, Dearing MD, et al. (2007) Determining biological tissue turnover using stable isotopes: the reaction progress variable. Oecologia 151: 175–189.

Cerling TE, Wittemyer G, Ehleringer JR, Remiene CH and Douglas‐Hamiltond I (2009) History of animals using isotope records (HAIR): a 6‐year dietary history of one family of African elephants. Proceedings of the National Academy of Sciences of the United States of America 106: 8093–8100.

Chamberlain CP, Blum JD, Holmes RT, et al. (1997) The use of isotope tracers for identifying populations of migratory birds. Oecologia 109: 132–141.

Chikaraishi Y, Steffan SA, Ogawa NO, et al. (2014) High‐resolution food webs based on nitrogen isotopic composition of amino acids. Ecology and Evolution 4: 2423–2449.

Clark I and Fritz P (1999) Environmental Isotopes in Hydrogeology. Boca Raton, FL: CRC Press.

Clementz MT, Holden P and Koch PL (2003) Are calcium isotopes a reliable monitor of trophic level in marine settings? International Journal of Osteoarchaeology 13: 29–36.

Costanzo SD, O'Donohue MJ, Dennison WC, Loneragan NR and Thomas M (2001) A new approach for detecting and mapping sewage impacts. Marine Pollution Bulletin 42: 149–156.

DeNiro MJ and Epstein S (1976) You are what you eat (plus a few permil): the carbon isotope cycle in food chains. Geological Society of America Abstracts with Programs 8: 834–835.

DeNiro MJ and Epstein S (1981) Influence of diet on the distribution of nitrogen isotopes in animals. Geochimica et Cosmochimica Acta 45: 341–351.

Evans KL, Newton J, Gaston KJ, et al. (2012) Colonisation of urban environments is associated with reduced migratory behaviour, facilitating divergence from ancestral populations. Oikos 121: 634–640.

Evershed RP, Bull ID, Corr LT, et al. (2007) Compound‐specific stable isotope analysis in ecology. In: Michener R and Lajtha K (eds) Stable Isotopes in Ecology and Environmental Science, pp. 480–540. Oxford: Blackwell.

Farquhar GD, O'Leary MH and Berry JA (1982) On the relationship between carbon isotope discrimination and the intercellular carbon dioxide concentration in leaves. Australian Journal of Plant Physiology 9: 121–137.

de Groot PA (ed) (2004) Handbook of Stable Isotope Analytical Techniques, vol. 1. Amsterdam: Elsevier.

de Groot PA (ed) (2009) Handbook of Stable Isotope Analytical Techniques, vol. 2. Amsterdam: Elsevier.

Grey J (2016) The incredible lightness of being methane‐fuelled: stable isotopes reveal alternative energy pathways in aquatic ecosystems and beyond. Frontiers in Ecology and Evolution 4, article no.8.

Hobson KA and Wassenaar LI (1997) Linking breeding and wintering grounds of neotropical migrant songbirds using stable isotope analysis of feathers. Oecologia 109: 142–148.

Hobson KA and Schell DM (1998) Stable carbon and nitrogen isotope patterns in baleen from eastern Arctic bowhead whales (Balena mysticetus). Canadian Journal of Fisheries and Aquatic Sciences 55: 2601–2607.

Hobson KA, Wassenaar LI and Taylor OR (1999) Stable isotopes (δD and δ13C) are geographic indicators of natal origins of Monarch butterflies in eastern North America. Oecologia 120: 397–404.

Hobson KA, Bowen GJ, Wassenaar LI, Ferrand Y and Lormee H (2004) Using stable hydrogen and oxygen isotope measurements of feathers to infer geographical origins of migrating European birds. Oecologia 141: 477–488.

Högberg P (1997) Tansley review no. 95: 15N natural abundance in soil–plant systems. New Phytologist 137: 179–203.

Inger R, Ruxton GD, Newton J, et al. (2006) Temporal and intrapopulation variation in prey choice of wintering geese determined by stable isotope analysis. Journal of Animal Ecology 75: 1190–1200.

Jackson AL, Inger R, Parnell AC and Bearhop S (2011) Comparing isotopic niche widths among and within communities: SIBER – Stable Isotope Bayesian Ellipses in R. Journal of Animal Ecology 80: 595–602.

Kvist A, Lindström Å, Green M, Piersma T and Visser GH (2001) Carrying large fuel loads during sustained bird flight is cheaper than expected. Nature 413: 730–732.

Maberly SC, Raven JA and Johnston AM (1992) Discrimination between 12C and 13C by marine plants. Oecologia 91: 481–492.

MacAvoy SE, Macko SA and Garman GC (1998) Tracing marine biomass into tidal freshwater ecosystems using stable sulfur isotopes. Naturwissenschaften 85: 544–546.

Marshall JD and Zhang J (1994) Carbon isotope discrimination and water‐use efficiency in native plants of the north‐central Rockies. Ecology 75: 1887–1895.

Matthews DE and Beauchemin D (eds) (2010) Encyclopedia of Mass Spectrometry, Volume 5: Elemental, Isotopic and Inorganic Mass Spectrometry. Oxford: Elsevier. forthcoming.

McKinney CR, McCrea JM, Epstein S, Allen HA and Urey HC (1950) Improvements in mass spectrometers for the measurement of small differences in isotope abundance ratios. Review of Scientific Instruments 21: 724–730.

McMahon K and McCarthy M (2016) Embracing Variability in Amino Acid δ15N Fractionation: Mechanisms, Implications, and Applications for Trophic Ecology. Paper presented to ISOECOL X, Tokyo, 2016.

Mendes S, Newton J, Reid RJ, Zuur AF and Pierce GJ (2007) Stable carbon and nitrogen isotope ratio profiling of sperm whale teeth reveals ontogenetic movements and trophic ecology. Oecologia 151: 605–615.

Minagawa M and Wada E (1984) Stepwise enrichment of 15N along food chains: further evidence and the relation between δ15N and animal age. Geochimica et Cosmochimica Acta 48: 1135–1140.

Mittermayr A, Hansen T and Sommer U (2014) Simultaneous analysis of δ13C, δ15N and δ34S ratios uncovers food web relationships and the trophic importance of epiphytes in an eelgrass Zostera marina community. Marine Ecology Progress Series 497: 93–103.

Moore JW and Semmens BX (2008) Incorporating uncertainty and prior information into stable isotope mixing models. Ecology Letters 11: 470–480.

Nehlich O (2015) The application of sulphur isotope analyses in archaeological research: a review. Earth Science Reviews 142: 1–17.

Neto JM, Newton J, Gosler AG and Perrins CM (2006) Using stable isotope analysis to determine the winter moult extent in migratory birds: the complex moult of Savi's warblers Locustella luscinioides. Journal of Avian Biology 37: 117–124.

Nielsen JM, Popp BN and Winder M (2015) Meta‐analysis of amino acid stable nitrogen isotope ratios for estimating trophic position in marine organisms. Oecologia 178: 631–642.

O'Leary MH (1988) Carbon isotopes in photosynthesis. Bioscience 38: 328–336.

Parkyn SM, Quinn JM, Cox TJ and Broekhuizen N (2005) Pathways of N and C uptake and transfer in stream food webs: an isotope enrichment experiment. Journal of the North American Benthological Society 24: 955–975.

Parnell A, Inger R, Bearhop S and Jackson AL (2008) SIAR: Stable Isotope Analysis in R. http://cran.r‐

Phillips DL and Gregg JW (2003) Source partitioning using stable isotopes: coping with too many sources. Oecologia 136: 261–269.

Phillips DL, Inger R, Bearhop S, et al. (2014) Best practices for use of stable isotope mixing models in food‐web studies. Canadian Journal of Zoology 92: 823–835.

Post DM (2002) Using stable isotopes to estimate trophic position: models, methods, and assumptions. Ecology 83: 703–718.

Powlson DS and Barraclough D (1993) Mineralization and assimilation in soil–plant systems. In: Knowles R and Blackburn TH (eds) Nitrogen Isotope Techniques, 311 pp. San Diego, CA: Academic Press.

Rau GH, Sweeney RE and Kaplan IR (1982) Plankton 13C:12C ratio changes with latitude: differences between northern and southern oceans. Deep‐Sea Research 29: 1035–1039.

Raven JR, Johnston AB, Kübler JE, et al. (2002) Mechanistic interpretation of carbon isotope discrimination by marine macroalgae and seagrasses. Functional Plant Biology 29: 355–378.

Reid WDK, Sweeting CJ, Wigham BD, et al. (2013) Spatial Differences in East Scotia Ridge Hydrothermal vent food webs: influences of chemistry, microbiology and predation on trophodynamics. PLoS One 8 (6): e65553.

Sellick MJ, Kyser TK, Wunder MB, Chipley D and Norris DR (2009) Geographic variation of strontium and hydrogen isotopes in avian tissue: implications for tracking migration and dispersal. PLoS One 4 (3): e4735.

Smith BN and Epstein S (1971) Two categories of 13C/12C ratios for higher plants. Plant Physiology 47: 380–384.

Stephenson RL, Tan FC and Mann KH (1984) Stable carbon isotope variability in marine macrophytes and its implications for food web studies. Marine Biology 81: 223–230.

Tieszen LL, Boutton TW, Tesdahl KG and Slade NA (1983) Fractionation and turnover of stable carbon isotopes in animal tissues: implications for δ13C analysis of diet. Oecologia 57: 32–37.

Vanderklift MA and Ponsard S (2003) Sources of variation in consumer‐diet δ15N enrichment; a meta‐analysis. Oecologia 136: 169–182.

Vander Zanden MJ, Shuter BJ, Lester N and Rasmussen JB (1999) Patterns of food chain length in lakes: a stable isotope study. American Naturalist 154: 406–416.

Vander Zanden MJ and Fetzer WW (2007) Global patterns of aquatic food chain length. Oikos 116: 1378–1388.

Vander Zanden HB, Soto DX, Bowen GJ and Hobson KA (2016) Expanding the isotopic toolbox: applications of hydrogen and oxygen stable isotope ratios to food web studies. Frontiers in Ecology and Evolution 4: 20.

Webb EC, Newton J, Stuart A, et al. (submitted) Sulphur‐isotope compositions of pig tissues from a controlled feeding study. Journal of Archaeological Science.

Wiencke C and Fischer G (1990) Growth and stable carbon isotope composition of cold‐water macroalgae in relation to light and temperature. Marine Ecology Progress Series 65: 283–292.

Witte U, Wenzhöfer F, Sommer S, et al. (2003) In situ experimental evidence of the fate of a phytodetritus pulse at the abyssal sea floor. Nature 424: 763–766.

Wunder MB and Norris DR (2008) Analysis and design for isotope‐based studies of migratory animals. In: Hobson KA and Wassenaar LI (eds) Tracking Animal Migration with Stable Isotopes, 144 pp. Amsterdam: Academic Press.

Yeakel YD, Bhat U, Elliott Smith ES and Newsome SD (2016) Exploring the isotopic niche: isotopic variance, physiological incorporation, and the temporal dynamics of foraging. Frontiers in Ecology and Evolution 4: 1.

Further Reading

Fry B (2006) Stable Isotope Ecology, 308 pp. New York: Springer.

Hobson KA and Wassenaar LI (eds) (2008) Tracking Animal Migration with Stable Isotopes, 144 pp. Amsterdam: Academic Press/Elsevier.

Michener R and Lajtha K (eds) (2007) Stable Isotopes in Ecology and Environmental Science, 566 pp. Oxford: Blackwell.

Speakman J (1997) Doubly Labelled Water: Theory and Practice, 416 pp. London: Springer.

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Newton, Jason(Sep 2016) Stable Isotopes as Tools in Ecological Research. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1002/9780470015902.a0021231.pub2]