Climate change is expected to increase the frequency of unpredictable weather in many parts of the world, and understanding how organisms will fare under this unpredictability is key. Unfortunately, little is understood about how living in environments that fluctuate unpredictably over time shapes individual condition. We will explore how oxidative stress—the imbalance between harmful reactive oxygen species and neutralizing antioxidants—differs across populations of superb starlings (Lamprotornis superbus) found across a range of different environments. We sampled free-living starlings across 8 populations in Kenya that experience different degrees of unpredictability in precipitation among years, where precipitation is a key driver of insect and food availability. We will explore the relationships between reactive oxygen metabolites, antioxidants, and oxidative balance, as well as whether oxidative balance is shaped by short-term deviations from total annual precipitation or long-term unpredictability in precipitation. Our preliminary results suggest that individuals in less predictable environments experience greater oxidative stress. We will discuss the implications of our results for how unpredictable environments may affect organisms in a rapidly changing world.