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Data from: Patterns of annual and seasonal immune investment in a temporal reproductive opportunist


Schultz, Elizabeth et al. (2020), Data from: Patterns of annual and seasonal immune investment in a temporal reproductive opportunist, Dryad, Dataset,


Historically, investigations of how organismal investments in immunity fluctuate in response to environmental and physiological changes have focused on seasonally breeding organisms that confine reproduction to seasons with mild environmental conditions and abundant resources. The red crossbill, Loxia curvirostra, is a songbird that can breed opportunistically if conifer seeds are abundant, on both short, cold, and long, warm days, providing an ideal system to investigate interactions between immunity, reproduction, and environmental fluctuations. In this study, we measured inter- and intra-annual variation in complement, natural antibodies, PIT54, and leukocytes in crossbills across four summers (2010-2013) and multiple seasons within one year (summer 2011-spring 2012). Overall, we observed substantial changes in crossbill immune investment among summers, with interannual variation driven largely by food resources, while seasonal variation was less pronounced and lacked a dominant predictor of immune investment. However, we found weak evidence that physiological processes (e.g., reproductive condition, moult) or abiotic factors (e.g., temperature, precipitation) affect immune investment. Collectively, this study suggests that a reproductively flexible organism may simultaneously invest in both reproduction and survival-related processes, potentially by exploiting rich patches with abundant resources. More broadly, these results emphasize the need for more longitudinal studies of trade-offs associated with immune investment.


Sigma Xi, Award: Grants in Aid of Research

American Ornithologists' Union, Award: Grant in Aid of Research

University of Wyoming/ National Park Service, Award: Small Grant Program

Society of Integrative and Comparative Biology, Award: Grant in Aid of Research

National Science Foundation, Award: 0744705,Graduate Research Fellowship