Baseline levels for antioxidant enzymes are provided for a set of ecologically relevant tropical and subtropical species. A quantitative comparison between the reported baseline values and literature data was performed. Seasonal and spatial variation in the biomarker response was studied and described. Multivariate approaches are a suitable tool to present and assess the results in multi-species and multi-biomarker studies. The multivariate antioxidant response was species-specific and strongly affected by seasonality.