The influence of time-of-day on estimates of taxonomic versus functional diversity in avian communities

Abstract

ABSTRACT Avian communities composed of a total of 79 species were sampled repeatedly at different times of day throughout the breeding season in Norfolk, Virginia, USA. Estimates of taxonomic diversity (species richness, Shannon index and probability of interspecific encounter) were highest in the morning, whereas estimates of functional diversity (functional richness, evenness, Rao’s entropy and mean distinctiveness) did not vary significantly throughout the day. These results suggest that estimates of taxonomic diversity in avian communities are biased by time-of-day, but measures of functional diversity may be more robust to such bias.