Ecological and life‐history traits may say little about birds’ vulnerability to high‐amplitude climatic fluctuations

Species-specific 'resistance' to impacts, such as accelerated climate change, and 'resilience' (if pressures are released), have important implications for long-term persistence. There have been some reports that species' traits may be related to resistance and resilience. We sought to determine whether guild membership, ecological versatility or life-history traits of woodland birds were related to species' resistance and resilience in the face of high-amplitude climatic fluctuations over two decades. There were four extensive survey programmes in temperate woodlands in Victoria, Australia, spanning the longest, most intense drought on record in the region (Big Dry: 1996-2010), a short, intense wet period (Big Wet: 2010-2012) and a return to very dry conditions (post-Big Wet: 2012-2016). We used species-specific reporting rates (RRs) to identify species having low resistance to the Big Dry, high resilience (recovery) during the Big Wet and low resistance over the whole survey period (1996-2016). Species falling into these three groups were compared with species not showing those responses, and the contrasting groups evaluated for systematic differences in ecological and life-history traits. Neither ecological nor life-history traits accounted for much variation in the three contrasts, suggesting that Big Dry- and overall-resistant species and Big Wet-resilient species were not coherent subsets of the terrestrial avifaunas. Given that species' traits were not related to vulnerability or to immunity from climatic pressures, we probably need to concentrate on species directly rather than groups defined by common life-history or ecological traits. Moreover, it almost certainly will be more useful to focus conservation management on reducing pervasive, manageable pressures (e.g. natural resource extraction, land-use change, reductions of greenhouse gas emissions), which is likely to provide assemblage-wide benefits for birds and other taxa.