The relationships between biodiversity and community population stability show connections between basic ecosystem structures and functions. These are some of the classic concerns of environmental and ecological research. Previous studies have revealed plant biodiversity and community stability are positively related at a local sampling-site scale. The present study used North American Breeding Bird Survey data over a longer time, larger area, and with greater taxonomic diversity, in order to understand how bird community population stability, at a continental scale, may be altered by biodiversity, functional traits, environmental factors and combinations thereof.

Species richness and mean and diversity of key life-history traits were selected as measures of biodiversity and function. Other measurements included factors such as weight, life span and fecundity.

Temperature, precipitation, and leaf area were selected as environmental factors. These data were collected from meteorological and satellite-based global spatial datasets.

Bird community population measurements were obtained from sites across North America for 1988-2017. The coefficient of variation of total biomass over time, an independent function, was used to determine stability.

Environmental factors, biodiversity, functional composition, and community stability were included in modeling and analysis which revealed that avian community population stability is best described using community functional combinations of ‘fast-slow’ traits.

‘Fast’ species-dominated communities, those with small bodies, a relatively brief hatchling-fledging phase, brief life spans, and high reproductive rates were more stable. The reverse was true for ‘slow’ species-dominated communities. This study suggests that fast-slow trait ratios, rather than species richness, are a more accurate predictor of North American bird community stability.