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Testing for human impacts in the mismatch of living and dead ostracode assemblages at nested spatial scales in subtropical lakes from the Bahamian archipelago

Published online by Cambridge University Press:  24 August 2018

Andrew V. Michelson
Affiliation:
Department of the Geophysical Sciences, University of Chicago, 5734 S. Ellis Avenue, Chicago, Illinois 60637, U.S.A. E-mail: amichelson@sunymaritime.edu, skidwell@uchicago.edu
Susan M. Kidwell
Affiliation:
Department of the Geophysical Sciences, University of Chicago, 5734 S. Ellis Avenue, Chicago, Illinois 60637, U.S.A. E-mail: amichelson@sunymaritime.edu, skidwell@uchicago.edu
Lisa E. Park Boush
Affiliation:
Center for Integrative Geosciences, University of Connecticut, Mansfield Road Unit 1045, Storrs, Connecticut 06269, U.S.A. E-mail: lisa.park_boush@uconn.edu
Jeanine L. Ash
Affiliation:
Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, 595 Charles Young Drive East, Box 951567, Los Angeles, California 90095-1567, U.S.A. E-mail: jlash@g.ucla.edu

Abstract

Naturally time-averaged accumulations of skeletal remains—death assemblages—provide reliable, albeit temporally coarse, information on the species composition and structure of communities in diverse settings, and their mismatch with local living communities usually signals recent human-driven ecological change. Here, we present the first test of live–dead mismatch as an indicator of human stress using ostracodes. On three islands along a gradient of human population density in the Bahamas, we compared the similarity of living and death assemblages in 10 lakes with relatively low levels of human stress to live–dead similarity in 11 physically comparable lakes subject to industrial, agricultural, or other human activities currently or in the past. We find that live–dead agreement in pristine lakes is consistently excellent, boding well for using death assemblages in modern-day and paleolimnological biodiversity assessments. In most comparison of physically similar paired lakes, sample-level live–dead mismatch in both taxonomic composition and species’ rank abundance is on average significantly greater in the stressed lakes; live–dead agreement is not lower in all samples from stressed lakes, but is more variable. When samples are pooled for lake-level and island-level comparisons, stressed lakes still yield lower live–dead agreement, but the significance of the difference with pristine lakes decreases—species that occur dead-only (or alive-only) in one sample are likely to occur alive (or dead) in other samples. Interisland differences in live–dead agreement are congruent with, but not significantly correlated with, differences in human population density. This situation arises from heterogeneity in the timing and magnitudes of stresses and in the extent of poststress recovery. Live–dead mismatch in ostracode assemblages thus may be a reliable indicator of human impact at the sample level with the potential to be a widely applicable tool for identifying impacted habitats and, perhaps, monitoring the progress of their recovery.

Type
Articles
Copyright
© 2018 The Paleontological Society. All rights reserved 

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Footnotes

*

Present address: Science Department SUNY Maritime College, 6 Pennyfield Avenue, Bronx, NY 10465-4198, U.S.A.

References

Literature Cited

Albano, P. G., Filippova, N., Steger, J., Kaufman, D. S., Tomašových, A., Stachowitsch, M., and Zuschin, M.. 2016. Oil platforms in the Persian (Arabian) Gulf: living and death assemblages reveal no effects. Continental Shelf Research 121:2134.Google Scholar
Alin, S. R., and Cohen, A. S.. 2004. The live, the dead, and the very dead: taphonomic calibration of the recent record of paleoecological change in Lake Tanganyika, East Africa. Paleobiology 30:4481.Google Scholar
Archuby, F. M., Adami, M., Martinelli, J. C., Gordillo, S., Boretto, G. M., and Malve, M. E.. 2015. Regional-scale compositional and size fidelity of rocky intertidal communities from the Patagonian Atlantic coast. Palaios 30:627643.Google Scholar
Benson, R. H., and Coleman, G. L. III. 1963. Recent marine ostracods from the eastern Gulf of Mexico. University of Kansas Paleontology Contributions, Arthropoda 2:152.Google Scholar
Bizjack, M. T., Kidwell, S. M., Velarde, R. G., Leonard-Pingel, J., and Tomašových, A.. 2017. Detecting, sourcing, and age-dating dredged sediments on the open shelf, southern California, using dead mollusk shells. Marine Pollution Bulletin 114:448465.Google Scholar
Brandão, S. N., Angel, M. V., Karanovic, I., Perrier, V., and Yasuhara, M.. 2017. World Ostracoda Database. Accessed through: World Register of Marine Species. http://www.marinespecies.org/aphia.php?p=taxdetails&id=1078, accessed 17 January 2018.Google Scholar
Cameron, N. G. 1995. The representation of diatom communities by fossil assemblages in a small acid lake. Journal of Paleolimnology 14:185223.Google Scholar
Casey, M. M., Dietl, G. P., Post, D. M., and Briggs, D. E. G.. 2014. The impact of eutrophication on commercial fishing on molluscan communities in Long Island Sound, USA. Biological Conservation 170:137144.Google Scholar
Chao, A., Chazdon, R. L., Colwell, R. K., and Shen, T.-J.. 2005. A new statistical approach for assessing compositional similarity based on incidence and abundance data. Ecology Letters 8: 148159.Google Scholar
Chase, J. M., and Knight, T. M.. 2013. Scale-dependent effect sizes of ecological drivers on biodiversity: Why why standardized sampling is not enough. Ecology Letters 16:1726.Google Scholar
Chiba, T., and Sato, S. I.. 2013. Invasion of Laguncula pulchella (Gastropoda: Naticidae) and predator–prey interactions with bivalves on the Tona coast, Miyagi prefecture, northern Japan. Biological Invasions 15:112.Google Scholar
Corrège, T. 1993. The relationship between water masses and benthic ostracod assemblages in the western Coral Sea, southwest Pacific. Palaeogeography, Palaeoclimatology, Palaeoecology 105:245266.Google Scholar
Daday, E. 1905. Untersuchungen über die Süsswasser-Mikrofauna Paraguays. Zoologica 18:1374.Google Scholar
Department of Statistics, Government of the Bahamas. 2012. 2010 Census of population and housing. Government Publication, Nassau, Bahamas.Google Scholar
Dietl, G. P., Kidwell, S. M., Brenner, M., Burney, D. A., Flessa, K. W., Jackson, S. T., and Koch, P. L.. 2015. Leveraging knowledge of the past to inform conservation and restoration. Annual Review of Earth and Planetary Sciences 43:79103.Google Scholar
Dixit, S. S., Dixit, A. S., and Smol, J. P.. 1989. Lake acidification recovery can be monitored using Chrysophycean microfossils. Canadian Journal of Fisheries and Aquatic Sciences 46:13091312.Google Scholar
Edwards, R. A. 1944. Ostracoda from the Duplin Marl (upper Miocene) of North Carolina. Journal of Paleontology 18:508528.Google Scholar
Escrivà, A., Smith, R. J., Aguilar-Alberola, J. A., Kamiya, T., Karanovic, I., Rueda, J., Schornikov, E. I., and Mesquita-Joanes, F.. 2012. Global distribution of Fabaeformiscandona subacuta: An an exotic invasive Ostracoda on the Iberian Peninsula. Journal of Crustacean Biology 32:949961.Google Scholar
Farnsworth, P. 1996. The influence of trade on Bahamian slave culture. Historical. Archaeology 30:123.Google Scholar
Ferguson, C. A., and Miller, A. I.. 2007. A sea change in Smuggler’s Smuggler’s Cove? Detection of decadal-scale compositional transitions in the subfossil record. Palaeogeography, Palaeoclimatology, Palaeoecology 254:418429.Google Scholar
Feser, K. M., and Miller, A. I.. 2014. Temporal dynamics of shallow seagrass-associated molluscan assemblages in St. Croix, U.S. Virgin Islands: Towards towards the calibration of taphonomic inertia. Palaios 29:218230.Google Scholar
Fitzpatrick, S. A., Kimball, K. C., Spergel, J., Michelson, A. V., and Leonard-Pingel, J.. 2015. Live/dead comparisons of ostracodes in temperate lakes reveal evidence of humans: Low low fidelity in impacted lakes, but high fidelity in remediated lakes. Geological Society of America Abstracts with Program 47:349.Google Scholar
Frenzel, P., and Boomer, I.. 2005. The use of ostracods from marginal marine, brackish waters as bioindicators of modern and Quaternary environmental change. Palaeogeography, Palaeoclimatology, Palaeoecology 225:6892.Google Scholar
Furtos, N. C. 1936. Fresh-water Ostracoda from Florida and North Carolina. American Midland Naturalist 17:491522.Google Scholar
Hassan, G. S. 2015. On the benefits of being redundant: low compositional fidelity of diatom death assemblages does not hamper the preservation of environmental gradients in shallow lakes. Paleobiology 41:154173.Google Scholar
Hazel, J. E. 1983. Age and correlation of the Yorktown (Pliocene) and Croatan (Pliocene and Pleistocene) Formations at the Lee Creek Mine in C. E. Ray, ed. Geology and Paleontology of the Lee Creek Mine, North Carolina, I. Smithsonian Contributions to Paleobiology 53:81199.Google Scholar
Hazel, J. E., and Cronin, T. M.. 1988. The North American genus Climacoidea Puri, 1956, and the tribe Campylocytherini (Neogene and Quaternary) in T. Hanai, N. Ikeya, and K. Ishizaki, eds. Evolutionary Biology of Ostracoda: Its Fundamentals and Applications. Proceedings of the Ninth International Symposium on Ostracoda. Kodansha/Elsevier(Tokyo/Amsterdam): 3956.Google Scholar
Jorissen, F. J., and Wittling, I.. 1999. Ecological evidence from live–dead comparisons of benthic foraminiferal faunas off Cape Blanc (Northwest northwest Africa). Palaeogeography, Palaeoclimatology, Palaeoecology 149:151170.Google Scholar
Keyser, D. 1975. Ostracode of the mangroves of south Florida, their ecology and biology. Bulletin American Paleontology 65:489499.Google Scholar
Keyser, D., and Schöning, C.. 2000. Holocene Ostracoda (Crustacea) from Bermuda. Senckenbergiana lethaea 80:567591.Google Scholar
Kidwell, S. M. 2007. Discordance between living and death assemblages as evidence for anthropogenic ecological change. Proceedings of the National Academy of Sciences, U.S.A 104:1770117706.Google Scholar
Kidwell, S. M. 2013. Time-averaging and the fidelity of modern death assemblages: Building building a taphonomic framework for conservation paleobiology. Palaeontology 56:487522.Google Scholar
Kidwell, S. M. 2015. Biology in the Anthropocene: Challenges challenges and insights from young fossils records. Proceedings of the National Academy of Science, s U.S.A. 112:49224929.Google Scholar
Kidwell, S. M., and Tomašových, A.. 2013. Implications of time-averaged death assemblages for ecology and conservation biology. Annual Review of Ecology, Evolution, and Systematics 44:539563.Google Scholar
Kidwell, S. M., and Tomašových, A.. 2013. Implications of time-averaged death assemblages for ecology and conservation biology. Annual Review of Ecology, Evolution, and Systematics 44:539563.Google Scholar
Kidwell, S. M., Best, M. M., and Kaufman, D. S.. 2005. Taphonomic trade-offs in tropical marine death assemblages: Differential time averaging, shell loss, and probable bias in siliciclastic vs. carbonate facies. Geology 33:729732.Google Scholar
Kidwell, S. M., Best, M. M., and Kaufman, D. S.. 2005. Taphonomic trade-offs in tropical marine death assemblages: differential time averaging, shell loss, and probable bias in siliciclastic vs. carbonate facies. Geology 33:729732.Google Scholar
Klie, W. 1939. Ostracoda aus den marinen Salinen von Bonaire, Curacao und Aruba. Capita Zoologica 8:119.Google Scholar
Kornicker, L. S. 1961. Ecology and taxonomy of recent Bairdiinae (Ostracoda). Micropaleontology 7:5570.Google Scholar
Kornicker, L. S. 1963. A seasonal study of living Ostracoda in a Texas bay (Redfish Bay) adjoining the Gulf of Mexico. Pubblicazioni della Stazione Zoologica di Napoli 33:4560.Google Scholar
Korpanty, C. A., and Kelley, P. H.. 2014. Molluscan live–dead agreement in anthropogenically stressed seagrass habitats: siliciclastic versus carbonate environments. Palaeogeography, Palaeoclimatology, Palaeoecology 410:113125.Google Scholar
Kosnik, M. A., Hua, Q., Kaufman, D. S., and Zawadzki, A.. 2015. Sediment accumulation, stratigraphic order, and the extent of time-averaging in lagoonal sediments: A a comparison of 210Pb and 14C/amino acid racemization chronologies. Coral Reefs 34:215229.Google Scholar
Kosnik, M. A., Hua, Q., Kaufman, D. S., and Wüst, R. A.. 2009. Taphonomic bias and time-averaging in tropical molluscan death assemblages: differential shell half-lives in Great Barrier Reef sediment. Paleobiology 35:565586.Google Scholar
Lord, A. R., Boomer, I., Brouwers, E., and Whittaker, J. E.. 2012. Ostracod taxa as paleoclimate indicators in the Quaternary. Pp. 3746 in D. J. Horne, J. Holmes, J. Rodriguez-Lazaro, and F. A. Viehberg, eds. Ostracoda as proxies for Quaternary climate change. Elsevier, Amsterdam.Google Scholar
Lotz, H. K., and McClenacha, L.. 2014. Historical ecology: Informing informing the future by learning from the past. Pp. 165200 in M. D. Bertness, J. F. Bruno, B. R. Silliman, and J. F. Stachowicz, eds. Marine community ecology and conservation. Sinauer Press, Sunderland, Mass.Google Scholar
Maddocks, R. F., and Iliffe, T. M., T. M. 1986. Podocopid Ostracoda of Bermudian Caves. Stygologia 2:2676.Google Scholar
Malkin-Curtis, D. S. 1960. Relation of environmental energy levels and ostracod biofacies in east Mississippi delta area. American Association of Petroleum Geologists 44:471494.Google Scholar
Martens, K., Schön, I., Meisch, C., and Horne, D. J.. 2008. Global diversity of ostracods (Ostracoda, Crustacea) in freshwater. Hydrobiologia 595:185193.Google Scholar
Michelson, A. V., and Park, L. E.. 2013. Taphonomic dynamics of lacustrine ostracodes on San Salvador Island, Bahamas: High high fidelity and evidence of anthropogenic modification. Palaios 28:195–135.Google Scholar
Michelson, A. V., and Park Boush, L.. 2017. A quantitative inference model for conductivity using non-marine ostracode assemblages on San Salvador Island, Bahamas: Paleosalinity paleosalinity records from two lakes. Palaeogeography, Palaeoclimatology, Palaeoecology 477:2739.Google Scholar
Michelson, A. V., Park, L. E., and Pan, J. J.. 2016. Discerning patterns of diversity from biogeographical distributions: testing models of metacommunity dynamics using non-marine ostracodes from San Salvador Island, Bahamas. Hydrobiologia 766:305319.Google Scholar
Mueller, G. W. 1894. Die Ostracoden des Golfes von Neapel und der angrenzenden Meeresabschnitte. in: Z. S. zu Neapel, ed., Fauna und Flora Golf von Neapel und der angrenzenden Meeres-Abschnitte: 1–404.Google Scholar
Müller, O. F. 1776. Zoologiae Danicae prodromus, seu animalium Daniae et Norvegiae indigenarum characteres, nomina, et synonyma imprimis popularium. I-XXXII:1282.Google Scholar
National Research Council. 2005. The geological record of ecological dynamics: understanding the biotic effects of future environmental change. National Academies Press, Washington, D.C.Google Scholar
Neely, W. 2012. The great Bahamian hurricanes of 1899 and 1932: the story of two of the greatest and deadliest hurricanes to impact the Bahamas. iUniverse, Bloomington, INInd.Google Scholar
Olszewski, T. D., and Kaufman, D. S.. 2015. Tracing burial history and sediment recycling in a shallow estuarine setting (Copano Bay, Texas) using postmortem ages of the bivalve Mulinia lateralis . Palaios 30:224237.Google Scholar
Olszewski, T. D., and Kidwell, D. S.. 2007. The preservational fidelity of evenness in molluscan death assemblages. Paleobiology 33:123.Google Scholar
Padmanabha, B., and Belagali, S. L.. 2008. Ostracods as indicators of pollution in the lakes of Mysore. Journal of Environmental Biology 29:415418.Google Scholar
Park, L. E. 2012. Comparing two long-term hurricane frequency and intensity records from San Salvador Island, Bahamas. Journal of Coastal Research 28:891902.Google Scholar
Park, L. E., Cohen, A. S., Martens, K., and Bralek, R.. 2003. The impact of taphonomic processes on interpreting paleoecologic changes in large lake ecosystems: ostracodes in Lakes Tanganyika and Malawi. Journal of Paleolimnology 30:127138.Google Scholar
Peterson, C. H. 1977. The paleoecological significance of undetected short-term temporal variability. Journal of Paleontology 51:976981.Google Scholar
Peterson, C. 1976. Relative abundances of living and dead molluscs in two Californian lagoons. Lethaia 9:137148.Google Scholar
Powell, E. N., Kuykendall, K. M., and Moreno, P.. 2017. The death assemblage as a marker for habitat and an indicator of climate change: Georges Bank, surfclams and ocean quahogs. Continental Shelf Research 142:1431.Google Scholar
Pyenson, N. D. 2011. The high fidelity of the cetacean stranding record: insights into measuring diversity by integrating taphonomy and macroecology. Proceedings of the Royal Society of London B: Biological Sciences 278:36083616.Google Scholar
Rick, T. C., and Lockwood, R.. 2013. Integrating paleobiology, archeology, and history to inform biological conservation. Conservation Biology 27:4554.Google Scholar
Rodriguez-Lazaro, J., and Ruiz-Muñoz, F.. 2012. A general introduction to ostracods: Morphologymorphology, distribution, fossil record and applications. Pp. 114 in D. J. Horne, J. Holmes, J. Rodriguez-Lazaro, and F. A. Viehberg, eds. Ostracoda as Proxies proxies for Quaternary climate change. Elsevier, Amsterdam.Google Scholar
Ruiz, F., Abad, M., Boderget, A. M., Carbonel, P., Rodrígues-Lázaro, J., and Yasuhara, M.. 2005. Marine and brackish-water ostracods as sentinels of anthropogenic impacts. Earth Earth-Science Reviews 72:89111.Google Scholar
Sbardella, C. A., J. Leonard-Pingel, J., and Michelson, A. V.. 2015. Live/dead analysis of molluscan communities in impacted temperate lacustrine ecosystems: High high fidelity in remediated lakes and evidence of anthropogenic impact. Geological Society of America Abstracts with Program 47:348.Google Scholar
Sharpe, R. W. 1909. A further report on the Ostracoda of the United States. U. S. National Museum Proceedings 35:399430.Google Scholar
Smith, A. J., and Horne, D. J.. 2002. Ecology of marine, marginal marine and nonmarine ostracodes. Pp. 3764 in J. A. Holmes, and A. R. Chivas, eds. The Ostracoda: applications in Quaternary research., Geophysical Monograph 131. American Geophysical Union, Washington, D.C.Google Scholar
Smith, J. A., and Dietl, G. P.. 2016. The value of geohistorical data in identifying a recent human-induced range expansion of a predatory gastropod in the Colorado River delta, Mexico. Journal of Biogeography 42:791800.Google Scholar
Smith, S. D. 2008. Interpreting molluscan death assemblages on rocky shores: Are are they representative of the regional fauna? Journal of Experimental Marine Biology and Ecology 366:151159.Google Scholar
Smol, J. P. 2008. Pollution of rivers and lakes: a paleoenvironmental perspective, 2nd ed. Blackwell, Malden, Mass.Google Scholar
Smol, J. P. 2008. Pollution of rivers and lakes: a paleoenvironmental perspective, 2nd edition. Blackwell Publishing, Malden, MA.Google Scholar
Smol, J. P., Charles, D. F., and Whitehead, D. R.. 1984. Mallomonadacean microfossils provide evidence of recent lake acidification. Nature 307:628630.Google Scholar
Swain, F. M. 1955. Ostracoda of San Antonio Bay, Texas. Journal of Paleontology 29:561646.Google Scholar
Swetnam, T. W., Allen, C. D., and Betancourt, J. L.. 1999. Applied historical ecology: using the past to manage for the future. Ecological applicationsApplications 9:11891206.Google Scholar
Sylvester-Bradley, P. C. 1947. Some ostracod genotypes. Annals and Magazine of Natural History, Series 11–13:192199.Google Scholar
Teeter, J. W. 1975. Distribution of Holocene marine Ostracoda from Belize, Parts 1-2 in Wantland, K. F. and Pusey, W. C., III, eds. Belize shelf-carbonate sediments, clastic sediments, and ecology. American Association of Petroleum Geologists 2:400499.Google Scholar
Tomašových, A., and Kidwell, S. M.. 2010. Effects of temporal scaling on species composition, diversity, and rank-abundance distributions in benthic assemblages. Paleobiology 36:672695.Google Scholar
Tomašových, A., and Kidwell, S. M.. 2011. Accounting for the effects of biological variability and temporal autocorrelation in assessing the preservation of species abundance. Paleobiology 37:332354.Google Scholar
Tomašových, A., and Kidwell, S. M.. 2017. Nineteenth-century collapse of a benthic marine ecosystem on the open continental shelf. Proceedings of the Royal Society of London B: Biological Sciences 284:2017032820170336.Google Scholar
Tsujimoto, Yasuhara, A. M., Nomura, R., Yamazaki, H., Sampei, Y., Hirose, K., and Yoshikawa, S.. 2008. Development of modern benthic ecosystems in eutrophic coastal oceans: the foraminiferal record over the last 200 years, Osaka Bay, Japan. Marine Micropaleontology 69:225239.Google Scholar
Vavrek, M. J. 2011. Fossil: Palaeoecological palaeoecological and palaeogeographical analysis tools. Palaeontologia Electronica 14:1T.Google Scholar
Viehberg, F. A., and Mesquita-Joanes, F.. 2012. Quantitative transfer function approaches in paleoclimate reconstructions using Quaternary ostracods. Pp. 4764 in D. J. Horne, J. Holmes, J. Rodriguez-Lazaro, and F. A. Viehberg, eds. Ostracoda as proxies for Quaternary climate change. Elsevier, Amsterdam.Google Scholar
Warwick, R. M., and Light, J.. 2002. Death assemblages of molluscs on St Martin’s Flats, Isle of Scilly: A a surrogate for regional biodiversity? Biodiversity and Conservation 11:99112.Google Scholar
Weber, K., and Zuschin, M.. 2013. Delta-associated molluscan life and death assemblages in the northern Adriatic Sea: Implications implications for paleoecology, regional diversity and conservation. Palaeogeography, Palaeoclimatology, Palaeoecology 370:7791.Google Scholar
Yanes, Y. 2012a. Anthropogenic effect recorded in the live-dead compositional fidelity of land snail assemblages from San Salvador Island, Bahamas. Biodiversity and Conservation 21:34453466.Google Scholar
Yanes, Y. 2012b. Shell taphonomy and fidelity of living, dead, Holocene, and Pleistocene land snail assemblages. Palaios 27:127136.Google Scholar
Yasuhara, M., Tittensor, D. P., Hillebrand, H., and Worm, B.. 2017. Combining marine macroecology and palaeoecology in understanding biodiversity: microfossils as a model. Biological Reviews 92:199215.Google Scholar
Yasuhara, M., Hunt, G., Breitburg, D., Tsujimoto, A., and Katsuki, K.. 2012. Human‐induced marine ecological degradation: micropaleontological perspectives. Ecology and Evolution 2:32423268.Google Scholar
Yasuhara, M., Yamazaki, H., Tsujimoto, A., and Hirose, K.. 2007. The effect of long-term spatiotemporal variations in urbanization-induced eutrophication on a benthic ecosystem, Osaka Bay, Japan. Limnology and Oceanography 52:16331644.Google Scholar
Zeppilli, D., Sarrazin, J., Leduc, D., Arbizu, P. M., Fontaneto, D., Fontanier, C., Gooday, A. J., Kristensen, R. M., Ivanenko, V. N., Sørensen, M. V., and Vanreusel, A.. 2015. Is the meiofauna a good indicator for climate change and anthropogenic impacts? Marine Biodiversity 45:505535.Google Scholar
Zuschin, M., and Ebner, C.. 2015. Compositional fidelity of death assemblages from a coral reef-associated tidal-flat and shallow subtidal lagoon in the northern Red Sea. Palaios 30:181191.Google Scholar