Multi-species analysis of stable carbon and nitrogen isotope data from Qalʿat al-Baḥrayn


  • Caitlin Bonham Smith The University of Auckland
  • Judith Littleton The University of Auckland


Qalʿat al-Baḥrayn, Stable isotope analysis, Islamic period, Bahrain archaeology, Multi-species approach


Isotope analysis of archaeological bone collagen is standard for investigating diet and animal husbandry practices. In the Arabian Peninsula, however, stable carbon and nitrogen isotope analysis is uncommon due to poor collagen preservation. We used a revised extraction protocol for fragile material and obtained collagen from Qalʿat al-Baḥrayn (QAB) adult human (n=19) and animal (n=45) bone.

Our work demonstrates surprising variation in adult diets. Despite burial adjacent to the coast and abundant fish remains at QAB, none of the adults was eating a primarily marine-based diet (mean δ13C = -17.9±1.5‰ and mean δ15N = 13.3±1.4‰). A range of diets seems to have been consumed from a completely terrestrial, C3 diet (n=3), to more mixed diets including variable, small amounts of marine or C4 resources (n=15). This heterogeneity is also found among the sheep, demonstrating variable feeding practices, including possible foddering with dried fish (mean δ13C = -16.8±2.1‰ and δ15N = 10.4 ±1.9‰). We hypothesize QAB is acting as a draw for different peoples and activity across the islands, while longer temporal change may be visible in the faunal bone. Our results demonstrate that a multi-species analysis of isotopes in Bahrain reveals economic and ecological diversity even within a small island ecosystem.


Ahsan M. 1979. Social life under the Abbasids. London: Longman.

Ambrose S.H. & Norr L. 1993. Experimental evidence for the relationship of the carbon isotope ratios of whole diet and dietary protein to those of bone collagen and carbonate. Pages 1–37 in J.B. Lambert & G. Grupe (eds), Prehistoric human bone. Archaeology at the molecular level. Berlin: Springer.

Beech M. 2005. The Faunal and botanical remains. Part 3: The fish bones. Pages 240–252 in T. Insoll (ed.), The Land of Enki in the Islamic era. London: Kegan Paul.

Belgrave J. 1973. Welcome to Bahrain. (8th edition). London: Augustan Press.

DeNiro M.J. 1985. Postmortem preservation and alteration of in vivo bone collagen isotope ratios in relation to palaeodietary reconstruction. Nature 317: 806–809.

DeNiro M.J. & Epstein S. 1978. Influence of diet on the distribution of carbon isotopes in animals. Geochimica et Cosmochimica Acta 42/5: 495–506.

Fernandes R., Grootes P., Nadeau M.J. & Nehlich O. 2015. Quantitative diet reconstruction of a Neolithic population using a Bayesian mixing model (FRUITS): The case study of Ostorf (Germany). American Journal of Physical Anthropology 158/2: 325–340.

Fiorentino G., Caracuta V., Casiello G., Longobardi F. & Sacco A. 2011. Studying ancient crop provenance: Implications from d13C and d15N values of charred barley in a Middle Bronze Age silo at Ebla (NW Syria). Rapid Communications in Mass Spectrometry 26: 327–335.

Fraser R.A., Bogaard A., Heaton T., Charles M., Jones G., Christensen B.T. … Stying A.K. 2011. Manuring and stable nitrogen isotope ratios in cereals and pulses: Towards a new archaeobotanical approach to the inference of land use and dietary practices. Journal of Archaeological Science 38/10: 2790–2804.

Gregoricka L.A. 2011. Mobility, exchange, and tomb membership in Bronze Age Arabia: A biogeochemical investigation. PhD thesis, Ohio State University. Available at: Accessed 20/08/2021.

Gregoricka L.A. 2013a. Geographic origins and dietary transitions during the Bronze Age in the Oman peninsula. American Journal of Physical Anthropology 152/3: 353–369.

Gregoricka L.A. 2013b. Residential mobility and social identity in the periphery: Strontium isotope analysis of archaeological tooth enamel from southeastern Arabia. Journal of Archaeological Science 40/1: 452–464.

Gregoricka L.A. 2014. Assessing life history from commingled assemblages: The biogeochemistry of inter-tooth variability in Bronze Age Arabia. Journal of Archaeological Science 47/1: 10–21.

Grupe G. 1995. ‘Preservation of collagen in bone from dry, sandy soil. Journal of Archaeological Science 22/2: 193–199.

Grupe G. & Schutkowski H. 1989. Dietary shift during the 2nd millennium BC in prehistoric Shimal, Oman peninsula. Paléorient 15/2: 77–84.

Guiry E.J. & Szpak P. 2020. Quality control for modern bone collagen stable carbon and nitrogen isotope measurements. Methods in Ecology and Evolution 11/9: 1049–1060.

Hutchins E. 2005. The Faunal and botanical remains. Part 2: Ecofactual analysis of the soil samples. Pages 232–239 in T. Insoll (ed.), The Land of Enki in the Islamic era. London: Kegan Paul.

Insoll T. 2005. Agriculture, diet, and the social role of food. Pages 253–280 in T. Insoll (ed.), The Land of Enki in the Islamic era. London: Kegan Paul.

Kervran M. 1999. Le Commerce maritime au Moyen Age. Dossiers d’Archaéologie (June): 46–53.

Kervran M. 2005. The 14th to 15th century village at Qal’at al-Bahrain. Pages 329–344 in M. Kervran, F. Hiebert & A. Rougeulle (eds), Qal’at al-Bahrain a trading outpost and military outpost 3rd millennium B.C.–17th century A.D. Turnhout: Brepols.

Kutterer A. & Uerpmann H-P. 2017. Neolithic nomadism in south-east Arabia – Strontium and oxygen isotope ratios in human tooth enamel from al-Buhais 18 and Umm al-Quwain 2 in the Emirates of Sharjah and Umm al-Quwain (UAE). Arabian Archaeology and Epigraphy 28/1: 75–89.

Larsen C. 1983. Life and land use on the Bahrain Islands: The geoarchaeology of an ancient society. Chicago: Chicago University Press.

Larsen C. 1986. Variation in Holocene land use patterns on the Bahrain Islands: Construction of a land use model. Pages 25–46 in S. Al Khalifa & M. Rice (eds), Bahrain through the ages. The archaeology. London: Kegan Paul.

Littleton J. 1987. A delicious torment: An analysis of dental pathology on historic Bahrain. MA thesis, Australian National University. doi: 10.25911/5D7A2711C299D.

Littleton J. & Frohlich B. 1989. An Analysis of dental pathology and diet on historic Bahrain. Paléorient 15/2: 59–75.

Littleton J., Allen M.S. & McFarlane G. 2015. Multi-species perspectives on anthropogenic environments: Dental pathology patterns, Marquesas Islands (Polynesia). Journal of Island and Coastal Archaeology 10/2: 277–301.

Littleton J., McFarlane G. & Allen M.S. 2020. Human-animal entanglements and environmental change: Multi-species approaches in remote Oceania. Pages 493–510 in G. Robbins Schug (ed.), The Routledge handbook of the bioarchaeology of climate and environmental change. Abingdon/New York: Routledge.

Lombard P. 2016. Qal’at al-Bahrain, ancient capital and harbour of Dilmun. The site museum. Bahrain: Bahrain Authority for Culture and Antiquities.

Lorimer J. 1915. Gazetteer of the Persian Gulf, Oman, and central Arabia. Calcutta: Superintendent Government Printing India.

Makarewicz C.A. & Sealy J. 2015. Dietary reconstruction, mobility, and the analysis of ancient skeletal tissues: Expanding the prospects of stable isotope research in archaeology. Journal of Archaeological Science 56: 146–158.

Al-Maslamani I., Le Vay L., Kennedy H. & Jones D.A. 2007. Feeding ecology of the grooved tiger shrimp Penaeus semisulcatus De Haan (Decapoda: Penaeidae) in inshore waters of Qatar, Arabian Gulf. Marine Biology 150/4: 627–637.

Al-Maslamani I., Walton M.E.M., Kennedy H.A., Al-Mohannadi M. & Le Vay L. 2013. Are mangroves in arid environments isolated systems? Life-history and evidence of dietary contribution from inwelling in a mangrove-resident shrimp species. Estuarine, Coastal and Shelf Science 124: 56–63.

Miller H., Baird D., Pearson J., Lamb A.L., Grove M., Martin L. & Garrard A. 2018. The origins of nomadic pastoralism in the eastern Jordanian steppe: A combined stable isotope and chipped stone assessment. Levant 50/3: 281–304.

Nesbitt M. 1993. Archaeobotanical evidence for early Dilmun diet at Saar, Bahrain. Arabian Archaeology and Epigraphy 4/1: 20–47.

Nielsen-Marsh C., Gernaey A., Turner-Walker G., Hedges R., Pike A.W.G. & Collins M. 2000. The chemical degradation of bone. Pages 439–454 in M. Cox & S. Mays (eds), Human osteology in archaeology and forensic science. Cambridge/New York: Cambridge University Press.

Olijdam E. 2000. Towards a more balanced assessment of land use on Bahrain during the City II period. Proceedings of the Seminar for Arabian Studies 30: 157–163.

Reid R.E.B., Lalk E., Marshall F. & Liu X. 2018. Carbon and nitrogen isotope variability in the seeds of two African millet species: Pennisetum glaucum and Eleusine coracana. Rapid Communications in Mass Spectrometry 32/19: 1693–1702.

Rice M. 1984. Dilmun discovered: The early years of archaeology in Bahrain. Manama: Addison-Wesley Longman Ltd.

Roberts P., Fernandes R., Craig O.E. & Larsen T. 2018. Calling all archaeologists: Guidelines for terminology, methodology, data handling, and reporting when undertaking and reviewing stable isotope applications in archaeology. Rapid Communications in Mass Spectrometry 32/5: 361–372.

Rougeulle A. 1982. Des ‘étuves’ à dattes à Bahrain et en Oman: Le problème de l’apparition des techniques de transformation de la datte. Paléorient 8/2: 67–77.

Sasaki T. 1990. Excavations at A’ali 1988/89. Proceedings of the Seminar for Arabian Studies 20: 111–129.

Schoeninger M.J. & DeNiro M.J. 1984. Nitrogen and carbon isotopic composition of bone collagen from marine and terrestrial animals. Geochimica et Cosmochimica Acta 48/4: 625–639.

Serret M.D., Al-Dakheel A.J., Yousfi S., Fernáandez-Gallego J.A., Elouafi I.A. & Araus J.L. 2020. Vegetation indices derived from digital images and stable carbon and nitrogen isotope signatures as indicators of date palm performance under salinity. Agricultural Water Management 230: 1–13.

Smith I. 2005. The Faunal and botanical remains. Part 1: The mammal, bird, reptile, and mollusc remains from Bilad al-Qadim. Pages 193–231 in T. Insoll (ed.), The Land of Enki in the Islamic era. London: Kegan Paul.

Tengberg M. & Lombard P. 2001. Environnement et économie végétale à Qal’at al-Bahreïn aux périodes Dilmoun et Tylos. Premiers éléments d’archéobotanique. Paléorient 27/1: 167–181.

Tuross N. 2012. Comparative decalcification methods, radiocarbon dates, and stable isotopes of the VIRI bones. Radiocarbon 54/3–4: 837–844.

Tuross N., Fogel M.L. & Hare P.E. 1988. Variability in the preservation of the isotopic composition of collagen from fossil bone. Geochimica et Cosmochimica Acta 52/4: 929–935.

Uerpmann H-P. & Uerpmann M. 1999. The animal economy of ancient Dilmun in the light of faunal remains from excavations at Saar and Qala’at al-Bahrain. Isimu 2: 635–646.

Uerpmann M. & Uerpmann H-P. 1994. Animal bone finds from excavation 520 at Qala’at al-Bahrain. Pages 417–444 in F. Højlund & H. Andersen (eds), Qala’at al-Bahrain. i. Aarhus: Aarhus University Press.

Van der Merwe N.J. 1982. Carbon isotopes, photosynthesis, and archaeology: Different pathways of photosynthesis cause characteristic changes in carbon isotope ratios that make possible the study of prehistoric human diets. American Scientist 70/6: 596–606.

Van Klinken G.J. 1999. Bone collagen quality indicators for palaeodietary and radiocarbon measurements. Journal of Archaeological Science 26/6: 687–695.

Vorenger J. 2016. Fishing at Qal’at al-Bahrain, archipelago of Bahrain, from the Early Dilmun (2200 BC) to the middle Islamic period (13–16th centuries AD). Cybium 40/1: 93–103. doi: 10.26028/cybium/2016-401-010.

Vorenger J. 2017. L’exploitation des faunes marines à Qal’at al-Bahreïn (île de Bahreïn, Golfe persique), du Bronze Ancien à l’époque islamique: Étude diachronique et comparaison avec les sites du Golfe. Université de Lyon. Available at: Accessed 20/08/2021.

Wada E., Mizutani H. & Minagawa M. 1991. The use of stable isotopes for food web analysis. Critical Reviews in Food Science & Nutrition 30/4: 361–371.

Wickham H. 2016. ggplot2: Elegant graphics for data analysis. New York: Springer.

Willis R.P. 1963. Geology of the Arabian Peninsula Bahrain, geological survey professional paper 560-E. Washington, DC: United States Department of the Interior.

Zazzo A., Munoz O. & Saliège J-F. 2014. Diet and mobility in a late Neolithic population of coastal Oman inferred from radiocarbon dating and stable isotope analysis. American Journal of Physical Anthropology 153/3: 353–364.



How to Cite

Bonham Smith, C., & Littleton, J. (2022). Multi-species analysis of stable carbon and nitrogen isotope data from Qalʿat al-Baḥrayn. Proceedings of the Seminar for Arabian Studies, 51, 35–54. Retrieved from