Meeting Abstract
Activation of the immune system requires individuals to allocate limited energy toward immunity, perhaps at the expense of reproduction. For example, a strong acute immune response may promote adult survival, but during the breeding season this may compromise offspring survival by interfering with parental behavior. To our knowledge, no studies have asked whether changes in parental behavior, such as visitation rate and brooding time, during an immune challenge may underlie a trade-off between immune function and offspring survival in free-living populations. We hypothesized that females experiencing immune system activation during reproduction would redirect their behavior away from offspring care, reducing offspring survival. To test our hypothesis, we injected 48 female dark-eyed juncos (Junco hyemalis) over the course of 2 breeding seasons at Mountain Lake Biological Station with a mild antigen (KLH) or a saline control. Females were injected during incubation to induce a robust immune response by 10 days post-injection, during the nestling phase when demands of brooding and feeding are high. Juncos are ground-nesting birds that are highly vulnerable to nest predation and time spent on or away from the nest may play a critical role in nestling survival. We video monitored nests 3d post-hatch to record visitation rate, feeding rate and time spent brooding. We also recorded fledging success. The data presented will shed light on whether activation of the immune system interacts with parental behavior to create a trade-off between immune response and offspring care.
