Climate extremes are among the most impactful aspects of climate change and are projected to increase in frequency in many regions of the world. Avian species are widely recognized as indicators of climate change and their interactions with climate extremes are well documented. However, few such studies have examined the effect of extremes at broad spatial and temporal scales and fewer have applied them to transitional ecosystems. Through climatologically aided mapping, we derived the number of temperature maximum and minimum extremes from 1996-2014 for the Central Great Plains and Cross Timbers ecoregions. Extremes were based on deviations from historical climate (1951-1980) data. Combined with long term bird survey data we analyzed how monthly temperature extremes impact bird abundance during subsequent breeding seasons. Comparing variability across species, functional groups, and habitat type, we evaluate their vulnerability to extreme events and effectiveness as indicators of broader climatic impacts.
Results/Conclusions
Preliminary analysis of 15 common species indicates that maximum temperature extremes have the greatest impact on species abundance. Grassland species displayed a positive response to extreme highs in maximum temperature for March while woodland species displayed consistently negative responses, regardless of month. Additionally, resident species showed consistently negative responses to extreme lows in maximum temperature. There was no overall trend among migratory and feeding guilds. The trends among habitat types and largely idiosyncratic responses at the species level may point to the importance of community structure over individual species requirements. Timing also appears to be critical as individual months may influence overall abundance disproportionately to overall trend. Forthcoming analysis should help to illuminate these patterns.