Meeting Abstract
Individuals integrate behavioral and physiological traits in order to protect themselves from infection. Environmental pollutants may affect a bird’s integrated defense system by reducing energy availability for self-maintenance behaviors (e.g., preening) and immune function. The Deep-Water Horizon oil spill released 779 million liters of crude oil into the Gulf of Mexico, and caused an estimated 200,000 bird mortalities. However, this damage estimate does not include sublethal behavioral and physiological effects from exposure to crude oil, and therefore may underestimate the harm of oil spills to avian populations. In this study, we were interested in whether crude oil ingestion impacts self-maintenance behaviors and immune function in birds. To do so, we dosed zebra finches (Taeniopygia guttata) daily with either peanut oil (control), or with 3.3 ml/kg or 10 ml/kg of crude oil. We measured white blood cell counts and complement activity on days 0, 7, and 15. We also video recorded the birds during the experiment and analyzed the videos for a suite of activity and self-maintenance behaviors. We found that crude oil exposure reduced activity and resulted in a tradeoff between self-maintenance behaviors. Additionally, our immune function data suggest that crude oil ingestion may cause inflammation. Collectively, our results suggest that exposure to crude oil could increase disease susceptibility, and therefore traditional damage estimates may insufficiently characterize the effects of oil spills on avian populations.
