Stable Isotopes in Nature Laboratory (SINLAB)
Canadian Rivers Institute, University of New Brunswick
What’s new in Stable Isotope Ecology?
October 2004
This issue’s feature paper:
Bolnick, D.I., Svanback, R., Fordyce, J.A., Yang, L.H., Davis, J.M., Hulsey, C.D., and Forister,
M.L. 2003. The ecology of individuals: incidence and implications of individual
specialization. The American Naturalist 161: 1-28.
This paper reviews the magnitude of within-population variation in a variety of organisms, using
gut contents and stable isotopes as measures (see also Matthews and Mazumder 2004 from last
newsletter). It serves as a reminder of the importance of considering variation in stable isotope
data in the context of both ecology and evolution.
Abstract (from http://www.journals.uchicago.edu/AN/journal/index.html):
Most empirical and theoretical studies of resource use and population dynamics treat conspecific
individuals as ecologically equivalent. This simplification is only justified if interindividual niche
variation is rare, weak, or has a trivial effect on ecological processes. This article reviews the
incidence, degree, causes, and implications of individual-level niche variation to challenge these
simplifications. Evidence for individual specialization is available for 93 species distributed
across a broad range of taxonomic groups. Although few studies have quantified the degree to
which individuals are specialized relative to their population, between-individual variation can
sometimes comprise the majority of the population's niche width. The degree of individual
specialization varies widely among species and among populations, reflecting a diverse array of
physiological, behavioral, and ecological mechanisms that can generate intrapopulation variation.
Finally, individual specialization has potentially important ecological, evolutionary, and
conservation implications. Theory suggests that niche variation facilitates frequency-dependent
interactions that can profoundly affect the population's stability, the amount of intraspecific
competition, fitness-function shapes, and the population's capacity to diversify and speciate
rapidly. Our collection of case studies suggests that individual specialization is a widespread but
underappreciated phenomenon that poses many important but unanswered questions.
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Stable Isotopes in Nature Laboratory (SINLAB)
Canadian Rivers Institute, University of New Brunswick
New articles:
Canadian Journal of Fisheries and Aquatic Sciences
Gregory-Eaves, I., Finney, B.P., Douglas, M.S.V., and Smol, J.P. 2004. Inferring sockeye
salmon (Oncorhynchus nerka) population dynamics and water quality changes in a stained
nursery lake over the past ~500 years. Canadian Journal of Fisheries and Aquatic Sciences 61:
1235-1246.
Ecological Applications
Dockx, C., Brower, L.P., Wassenaar, L.I., and Hobson, K.A. 2004. Do North American
monarch butterflies travel to Cuba? Stable isotope and chemical tracer techniques.
Ecological Applications 14: 1106-1114.
Bustamante, M.M.C., Martinelli, L.A., Silva, D.A., Camargo, P.B., Klink, C.A., Domingues,
T.F., and Santos, R.V. 2004. 15N natural abundance in woody plants and soils of central
Brazilian savannas (Cerrado). Ecological Applications 14 (Suppl.): 200-213.
Bernardes, M.C., Martinelli, L.A., Krusche, A.V., Gudeman, J., Moreira, M., Victoria, R.L.,
Ometto, J.P.H.B., Ballester, M.V.R., Aufdenkampe, A.K., Richey, J.E., and Hedges, J.I. 2004.
Riverine organic matter composition as a function of land use changes, Southwest Amazon.
Ecological Applications 14 (Suppl.): 263-279.
Ecology
No new papers
Freshwater Biology
No new papers
Marine Ecology Progress Series
Duineveld, G.C.A., Lavaleye, M.S.S., and Berghuis, E.M. 2004. Particle flux and food supply
to a seamount cold-water coral community (Galicia Bank, NW Spain). Marine Ecology
Progress Series 277: 13-23.
Ruiz-Cooley, R.I., Gendron, D., Aguiniga, S., Mesnick, S., and Carriquiry, J.D. 2004. Trophic
relationships between sperm whales and jumbo squid using stable isotopes of C and N.
Marine Ecology Progress Series 277: 275-283.
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Stable Isotopes in Nature Laboratory (SINLAB)
Canadian Rivers Institute, University of New Brunswick
Guest, M.A., Connolly, R.M., and Loneragan, N.R. 2004. Carbon movement and assimilation
by invertebrates in estuarine habitats at a scale of metres. Marine Ecology Progress Series
278: 27-34.
Bouillon, S., Moens, T., Overmeer, I., Koedam, N., and Dehairs, F. 2004. Resource utilization
patterns of epifauna from mangrove forests with contrasting inputs of local versus
imported organic matter. Marine Ecology Progress Series 278: 77-88.
Oecologia
Dodds, W.K., Marti, E., Tank, J.L., Pontius, J., Hamilton, S.K., Grimm, N.B., Bowden, W.B.,
McDowell, W.H., Peterson, B.J., Valett, H.M., Webster, J.R., and Gregory, S. 2004. Carbon
and nitrogen stoichiometry and nitrogen cycling rates in streams. Oecologia 140: 458-467.
Tillberg, C.V. 2004. Friend or foe? A behavioral and stable isotopic investigation of an antplant symbiosis. Oecologia 140: 506-515.
Carleton, S.A., Wolf, B.O., and Martinez del Rio, C. 2004. Keeling plots for hummingbirds: a
method to estimate carbon isotope ratios of respired CO2 in small vertebrates. Oecologia
141: 1-6.
Arndt, S.K., Kahmen, A., Arampatsis, C., Popp, M., and Adams, M. 2004. Nitrogen fixation
and metabolism by groundwater-dependent perennial plants in a hyperarid desert.
Oecologia 141: 385-394.
Bennett, J.N. and Prescott, C.E. 2004. Organic and inorganic nitrogen nutrition of western
red cedar, western hemlock and salal in mineral N-limited cedar-hemlock forests.
Oecologia 141: 468-476.
Steinmann, K., Siegwolf, R.T.W., Saurer, M., and Kurner, C. 2004. Carbon fluxes to the soil in
a mature temperate forest assessed by 13C isotope tracing. Oecologia 141: 489-501.
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