STRONTIUM & LEAD ISOTOPE EVIDENCE FOR PALEOMOBILITY OF INTRODUCED FAUNA IN THE CARIBBEAN John KRIGBAUM 1 , Christina M. GIOVAS 2 , George D. KAMENOV 3 1 Department of Anthropology, University of Florida, Gainesville FL, USA; krigbaum@ufl.edu 2 Center for Comparative Archaeology, University of Pittsburgh; Pittsburgh PA, USA; cmgiovas@upitt.edu 3 Department of Geological Sciences, University of Florida, Gainesville FL, USA; kamenov@ufl.edu INTRODUCTION Investigations into the introduction of non-native animals in the Caribbean during the Ceramic Age (ca. 2500-500 BP) address the economic and socio- symbolic significance of these taxa, their place in multi-scalar networks of interisland/continental interaction, and the impact of exotic species on island ecosystems (e.g., Giovas et al. 2012; LeFebvre & deFrance 2014; Laffoon et al. 2013; Wing 2008). In this research, our pivotal questions concern the degree of animal management practiced by Amerindians, the nature of trade and exchange, and the impact of introduced fauna on endemic species. This requires data on the long-term viability of introduced populations, timing and frequency of species (re)introductions, and degree of control exerted on non- native fauna by people. Two of these translocated species, agouti (Dasyprocta sp.) and opossum (Didelphis sp.), are widely distributed across the Lesser Antilles as butchered, fragmented remains recovered from archaeological middens (Fig. 1). While these fauna derive ultimately from South America or Trinidad, their proximate origins, which may reflect locally established Antillean populations and interisland transfers of animals, are unknown. Here we employ strontium ( 87 Sr/ 86 Sr) and lead ( 206 Pb/ 204 Pb, 207 Pb/ 204 Pb, 208 Pb/ 204 Pb; hereafter 20n Pb/ 204 Pb) isotope ratios from agouti and opossum dental enamel, terrestrial snail shell, and geologic samples from Nevis (northern Lesser Antilles) and Carriacou and Mustique (Grenadines Archipelago, southern Lesser Antilles) to investigate the interisland movement of exotic animals in the prehistoric Caribbean (Fig. 1). RESULTS Results are presented in Table 1 and Figures 5 and 6. Published data for geologic (volcanic) Pb isotopes in the Lesser Antilles, including nearby islands of the Grenadines, St. Vincent and Grenada, as well as bioavailable Sr (plant samples) for Nevis, are employed to provide context for results (www.earthchem.org/pe td; Laffoon et al. 2012). REFERENCES CITED Fitzpatrick, S.M. et al. 2008. Preliminary petrographic and chemical analyses of ceramics from Carriacou, southern Grenadines, West Indies. J Caribbean Archaeology 8:59-82. Fitzpatrick, S.M. et al. 2009. Evidence for inter-island transport of heirlooms: Luminescence dating and petrographic analysis of ceramic inhaling bowls from Carriacou, West Indies. J Archaeological Science 36:596-606. Giovas, C.M. 2013. Foraging Variability in the Prehistoric Caribbean: Multiple Foraging Optima, Resource Use, and Anthropogenic Impacts on Carriacou, Grenada. PhD Thesis. Univ of Washington, Seattle. Giovas, C.M. et al. 2012. New records for prehistoric introduction of Neotropical mammals to the West Indies: Evidence from Carriacou, Lesser Antilles. J of Biogeography 39:476-487. Giovas, C.M. et al. 2013. Intensifying collection and size increase of the tessellated nerite snail (Nerita tessellata) at the Coconut Walk Site, Nevis, northern Lesser Antilles, AD 890-1440. J of Archaeological Science, 40:424-438. Hofman, C.L., Hoogland, M.L.P. 2011. Unraveling the multi-scale networks of mobility and exchange in the pre-colonial Caribbean, in: Hofman, C.L., van Duijvenbode, A. (Eds.), 2011. Communities in Contact. Sidestone Press, Leiden, pp. 15-43. Kamenov, G.D. et al. 2004. Optimization of mixed Pb-Tl solutions for high precision isotopic analyses by MC-ICP-MS. J Analytical Atomic Spectrometry 19:1262-1267. Kamenov, G.D. et al. 2006. A simple method for rapid, high-precision isotope analyses of small samples by MC-ICP-MS. Eos Transactions AGU 87, Fall Meeting Supplement, V21A-0542. Kaye, Q. et al. 2010. Beyond Time Team: Archaeological investigations at Coconut Walk, Nevis, West Indies. Papers from the Institute of Archaeology 20: 137-147. LeFebvre, M.J. & S. deFrance. 2014. Guinea Pigs in the Pre-Columbian West Indies. J Island and Coastal Archaeology 9:16-44. Laffoon, J.E. et al. 2012. Spatial variation of biologically available strontium isotopes ( 87 Sr/ 86 Sr) in an archipelagic setting: A case study from the Caribbean. J Archaeological Science 39:2371-2384. Laffoon, J.E. et al. 2013. The Movement and exchange of dogs in the prehistoric Caribbean: An isotopic investigation. International Journal of Osteoarchaeol. DOI: 10.1002/oa.2313 Smith et al. 2004. Petrogenesis of orthopyroxene- and amphibole-bearing andesites, Mustique, Grenadine Islands, Lesser Antilles Arc. The Island Arc 13:73-94. Valentine, B., et al. 2008. Reconstructing Neolithic groups in Sarawak, Malaysia through lead and strontium isotope analysis. J Archaeological Science 35, 1463-1473. Wing, E.S., 2008. Native pets and camp followers in the West Indies, in: Reitz, E., Scarry, C.M., Scudder, S.J. (Eds.), Case Studies in Environmental Archaeology, second ed. Springer, New York, pp. 405-425. METHODS Sample analysis took place at the University of Florida following protocols described in Valentine et al. (2008). 87 Sr/ 86 Sr and 20n Pb/ 204 Pb isotope ratios were measured using a NuPlasma multiple-collector inductively-coupled plasma-mass spectrometer (MC-ICP-MS) based on techniques described in Kamenov et al. (2004, 2006) and Valentine et al. (2008). 87 Sr/ 86 Sr is relative to NBS 987 = 0.71024 (+/-0.00003, 2σ). Pb isotopes are relative to NBS 981 206 Pb/ 204 Pb = 16.937 (±0.004, 2σ), 207 Pb/ 204 Pb = 15.490 (±0.003, 2σ), and 208 Pb/ 204 Pb = 36.695. (±0.009, 2σ). Figure 1. Map showing locations discussed in text and anthropogenic distribution of opossum (far left) and agouti (near left) in pre- Columbian Lesser Antilles Figure 2. Carriacou geology; Sabazan and Grand Bay are situated on limestone and calcarenite beds, volcanic-derived conglomerates, sand-stone, and silt-stone (after Donovan & Jackson 2013). Figure 4. Nevis geology; Coconut Walk is located on un-differentiated flank deposits (primarily block and ash flows) of the Nevis Peak volcanic center (after Nevis Geologic Profile, UWI Seismic Research Centre). Table 1. Analyzed Sr and Pb isotope ratios. Superscript letters indicate intra-individual samples. Figure 5. 87 Sr/ 86 Sr ratios from Carriacou, Mustique, and Nevis. Plant 87 Sr/ 86 Sr from Laffoon et al. (2012). Figure 6. 207 Pb/ 204 Pb plotted against 206 Pb/ 204 Pb ratios. Op = opossum, Ag = agouti. Sr Variability Within Sampling Locations Disparities occur with animal and rock samples from the same field collection point. Examples: • Volcanic rock (MUS-9) from Macaroni Bay has the lowest recorded 87 Sr /86 Sr ratios (0.70404), while snail shell (SH-14-17) from Macaroni Bay has one of the highest (0.7890). SH-14-17, collected ca. 60m from the sea, probably incorporates seaspray- derived Sr (modern seawater = 0.7092), as does SH-14-16 (0.70915) from Lagoon Bay. • Coastal snail specimens from Carriacou (Grand Bay, Sabazan) and Nevis (Coconut Walk) exhibit a range of Sr isotopes, some well below the present-day seawater Sr ratio. • Nevis snails SH-13-07 and SH-13-09 from Coconut Walk are consistent with published Sr ratios from plants (Laffoon et al. 2012), but SH-13-08 is considerably higher (Fig. 5). Geologic Pb Variability • 206 Pb/ 204 Pb and 207 Pb/ 204 Pb ratios for Carriacou geologic samples fall within the range defined by published Pb ratios for Grenadines volcanic rocks. Mustique ratios lie close to Pb ratios from the Grenadines and within the upper Pb spread for Grenada (Fig. 6). • Comparative bioavailable Pb signals are unavailable/unpublished. Due to geological processes and the very low Pb content in seawater, however, sediment and volcanic rocks may overlap in Pb isotope space in the region; e.g., Pb isotopes in sedimentary rock CAR-12 plot within the Grenadines volcanic rocks field. Volcanic rocks may, therefore, be representative of the bioavailable Pb in the region. Faunal Pb Variability • Carriacou agouti and opossum 206 Pb/ 204 Pb and 207 Pb/ 204 Pb ratios exhibit almost as much variability as all the Lesser Antilles, contrasting with Carriacou and Mustique geologic samples, which are limited in their spread (Fig. 6). • The majority of agouti and opossum samples outside the range of Grenadines’ Pb ratios align with Grenada or St. Vincent Pb ratios and may originate from these islands (Fig. 6). • 206 Pb/ 204 Pb and 207 Pb/ 204 Pb ratios for Nevis agoutis are low and plot outside the Lesser Antilles range (Table 1, excluded from Fig. 6.). This may indicate movement of animals from an island source with low radiogenic Pb. Possible places of origin are the Greater Antilles and/or South America. The latter is more likely given agouti’s prehistoric range. CONCLUSION Overall results indicate possible transfers of agouti and opossum between islands of the Lesser Antilles, but further analysis is required to substantiate these findings. Preliminary results underscore the necessity of deriving island specific Sr ratios based on robust environmental sampling and the need for further sampling of animal tooth enamel from archaeological sources to characterize bioavailable Pb in the islands. This investigation contributes to our evolving understanding of the economic and social significance of introduced Neotropical animals in the pre-Columbian Caribbean and lays a foundation for future animal and human paleomobility studies in the region. ACKNOWLEDGMENTS We wish to thank Ben Valentine and Ashley Sharpe for assistance with sample preparation and analysis, and Scott Fitzpatrick and Meg Clark for providing zooarchaeological samples from Coconut Walk, Nevis. This research was conducted with financial support from the University of Pittsburg and University of Oregon. BACKGROUND Samples analyzed for 87 Sr/ 86 Sr (n = 35) and 20n Pb/ 204 Pb (n = 19) ratios are reported in (Table 1). Agouti and opossum samples derive from the Sabazan archaeological site (ca. AD 400 – 1400) on Carriacou (n = 11) and the Coconut Walk site (ca. AD 800 – 1400) on Nevis (n = 4). Carriacou and Nevis were involved in prehistoric interaction networks that included the movement of utilitarian and ritual objects and raw materials (Fitzpatrick et al. 2008, 2009; Giovas 2013; Hofman & Hoogland 2011; Kaye et al. 2010). Archaeological and modern snail shell (n = 12) and volcanic and carbonate rock samples (n = 8) were analyzed from multiple sampling locations on Nevis, Carriacou, and Mustique to help establish local bioavailable and geologic Sr and Pb ratios. Snail shell analysis includes only Sr ratios. Tooth enamel samples consist of in situ premolars/molars in alveolar bone. We make no assumptions about the local/non-local status of mammal remains, but assume that land snail shells reflect local bioavailable Sr isotopes. Carriacou is characterized by mixed volcanic/sedimentary geology (Fig. 2), while Mustique and Nevis are composed principally of volcanic materials (Figs. 3 & 4) (Donovan & Jackson 2013; Smith et al. 2004; UWI Seismic Research Centre, www.uwiseismic.com/Downloads/nevis4website.pdf). Figure 3. Mustique geology; composed of Oligocene volcano- sedimentary rocks interbedded with or intruded into by basaltic and andesitic lavas, dykes, and sills (after Smith et al. 2004). DISCUSSION Faunal Sr Variability Considerable overall variation exists in 87 Sr /86 Sr ratios. Small sample sizes necessitate caution in interpretation. • Nevis fauna: range: 0.70650 – 0.70858,   = 0.70741, σ = ±0.00079 (plants excluded). Agouti ratios are consistent with the large bioavailable Sr variability registered by snails and plants. • Carriacou fauna: range: 0.706731 – 0.70892,   = 0.70770, σ = ±0.00060. Carriacou agouti and snails and Nevis agouti exhibit Sr isotopic heterogeneity not evident in Carriacou opossums. Intra-island Sr Variability Disparity between 87 Sr /86 Sr ratios of biological samples (higher) and geologic material (lower) likely reflects differences in the geologic representativeness of sample types and the need to further sample heterogeneous island geology. Examples: • Carbonate rock (CAR-12, 0.70843) from the Carriacou and Grand Bay Formations (CGBF: volcanic, Miocene limestone, and calcarenite deposits; Fig. 2) aligns with Oligocene-Miocene seawater 87 Sr /86 Sr ratios (0.7079 – 0.7090) and is within the range for Sabazan snails from the CGBF. However, CAR-2 (sedimentary rock), also from the CGBF, exhibits a 87 Sr /86 Sr ratio (0.70631) suggesting considerable incorporation of volcanogenic clasts at this location. • MUS-8 and MUS-9 are consistent with a range of Sr ratios (0.70401 – 0.70457) reported for basalts and andesites from the island (Smith et al. 2004), but MUS-13 (0.70540), from the lower volcaniclastic unit in southern Mustique falls above this reported range (Fig. 3). 0.70350 0.70450 0.70550 0.70650 0.70750 0.70850 0.70950 EN-13-2568 - agouti EN-13-2569- agouti EN-13-2570 - agouti EN-13-2571 - agouti SH-13-07 - arch snail SH-13-08 - arch snail SH-13-09 - arch snail plant plant plant plant plant SH-14-16 - mod snail SH-14-17 - mod snail MUS-8 - geologic MUS-9 - geologic MUS-13 - geologic EN-13-2558 - agouti EN-13-2559 - agouti EN-13-2560 - agouti EN-13-2561 - agouti EN-13-2562 - agouti EN-13-2563 - agouti EN-13-2567 - agouti EN-13-2564 - opossum EN-13-2565 - opossum EN-13-2566 - opossum EN-13-2573 - opossum SH-13-02 - arch snail SH-13-05 - arch snail SH-13-06 - arch snail SH-13-03 - mod snail SH-14-10 - mod snail SH-13-04 - mod snail SH-14-19 - mod snail CAR-2 - geologic CAR-12 - geologic CAR-27- geologic CAR-29 - geologic CAR-33 - geologic 87 Sr/ 86 Sr Nevis Mustique Carriacou 87 Sr/ 86 Sr Ag Ag Ag Ag Ag Ag Ag agouti enamel opossum enamel terrestrial snail shell geologic (carbonate & volcanic) plant Gun Point Belaire Mt. Pleasant Rutland Bay Macaroni Bay Island Locality Sample # Taxon Sample Type 87 Sr/ 86 Sr 206 Pb/ 204 Pb 207 Pb/ 204 Pb 208 Pb/ 204 Pb Carriacou Sabazan EN-13-2558 a agouti arch enml 0.70745 18.670 15.666 38.444 Carriacou Sabazan EN-13-2559 a agouti arch enml 0.70724 18.493 15.582 38.131 Carriacou Sabazan EN-13-2560 a agouti arch enml 0.70698 18.670 15.647 38.386 Carriacou Sabazan EN-13-2561 agouti arch enml 0.70705 19.654 15.733 38.921 Carriacou Sabazan EN-13-2562 agouti arch enml 0.70791 18.685 15.619 38.295 Carriacou Sabazan EN-13-2563 agouti arch enml 0.70766 18.881 15.660 38.528 Carriacou Sabazan EN-13-2567 agouti arch enml 0.70673 19.037 15.691 38.737 Carriacou Sabazan EN-13-2564 opossum arch enml 0.70748 19.512 15.721 38.884 Carriacou Sabazan EN-13-2565 opossum arch enml 0.70791 19.040 15.686 38.743 Carriacou Sabazan EN-13-2566 b opossum arch enml 0.70779 19.080 15.575 38.259 Carriacou Sabazan EN-13-2573 b opossum arch enml 0.70762 20.320 15.793 39.322 Carriacou Sabazan SH-13-02 land snail arch shell 0.70892 18.450 15.624 38.209 Carriacou Sabazan SH-13-03 land snail mod shell 0.70874 18.725 15.653 38.523 Carriacou Sabazan SH-14-10 land snail mod shell 0.70873 - - - Carriacou Grand Bay SH-13-04 land snail mod shell 0.70781 - - - Carriacou Grand Bay SH-13-05 land snail arch shell 0.70753 - - - Carriacou Grand Bay SH-13-06 land snail arch shell 0.70766 - - - Carriacou Gun Point SH-14-19 land snail mod shell 0.70736 - - - Carriacou ~12°27'43.68"N, 61°25'59.58"W CAR-2 geologic - sedimentary 0.70631 - - - Carriacou Mt Pleasant CAR-12 geologic - sedimentary 0.70843 19.404 15.751 39.227 Carriacou ~12°29'16.16"N, 61°27'2.89"W CAR-27 geologic - volcanic 0.70480 19.506 15.733 38.919 Carriacou Belaire CAR-29 geologic - volcanic 0.70525 19.501 15.743 38.985 Carriacou Gun Point CAR-33 geologic - volcanic 0.70492 - - - Mustique Lagoon Bay SH-14-16 land snail mod shell 0.70915 - - - Mustique Macaroni Bay SH-14-17 land snail mod shell 0.70890 - - - Mustique Rutland Bay MUS-8 geologic - volcanic 0.70440 19.650 15.722 38.991 Mustique Macaroni Bay MUS-9 geologic - volcanic 0.70404 19.528 15.716 38.923 Mustique ~2°52'2.46"N, 61°10'59.29"W MUS-13 geologic - volcanic 0.70540 19.722 15.743 39.102 Nevis Coconut Walk EN-13-2568 agouti arch enml 0.70659 - - - Nevis Coconut Walk EN-13-2569 agouti arch enml 0.70766 18.465 15.576 38.090 Nevis Coconut Walk EN-13-2570 agouti arch enml 0.70650 18.386 15.575 38.044 Nevis Coconut Walk EN-13-2571 agouti arch enml 0.70680 - - - Nevis Coconut Walk SH-13-07 land snail arch shell 0.70776 - - - Nevis Coconut Walk SH-13-08 land snail arch shell 0.70858 - - - Nevis Coconut Walk SH-13-09 land snail arch shell 0.70795 - - - Opossum (Didelphis sp.) Agouti (Dasyprocta sp.)