The current exposure of species assemblages to high environmental variability may grant them resilience to future increases in climatic variability. In globally threatened coral reef ecosystems, management seeks to protect resilient reefs within variable environments. Yet, our lack of understanding for the determinants of coral population performance within variable environments hinders forecasting the future reassembly of coral communities. Here, using Integral Projection Models, we compare the short- (i.e., transient) and long-term (i.e., asymptotic) demographic characteristics of tropical and subtropical coral assemblages to evaluate how thermal variability influences the structural composition of coral communities over time. Exploring spatial variation across the dynamics of functionally different competitive, stress-tolerant, and weedy coral assemblages in Australia and Japan, we show that coral assemblages trade-off long-term performance for transient potential in response to thermal variability. We illustrate how coral assemblages can reduce their susceptibility towards environmental variation by exploiting volatile short-term demographic strategies, thus enhancing their persistence within variable environments. However, we also reveal considerable variation across the vulnerability of competitive, stress-tolerant, and weedy coral assemblages towards future increases in thermal variability. In particular, stress-tolerant and weedy corals possess an enhanced capacity for elevating their transient potential in response to environmental variability. Accordingly, despite their current exposure to high thermal variability, future climatic shifts threaten the structural complexity of coral assemblages, derived mostly from competitive coral taxa within highly variable subtropical environments, emulating the degradation expected across global coral communities.

Recreational fisheries are of global socio-ecological importance and contribute significantly to local economies and fisheries harvests. In some regions of Australia, organized recreational fishing activities have existed for over 150 yr. However, historical understanding of the spatio-temporal development and resource usage of recreational fisheries has been hampered by the lack of continuous time-series catch and effort data. This study used historical newspaper articles of reported landings by fishing clubs to reconstruct catch rate trends and evaluate changes in catch composition of marine recreational fishing activities in Moreton Bay, Queensland, Australia, from 1920-1984. Using generalized additive mixed models, 2 catch rate metrics (no. of fish fisher-1 trip-1 and kg fish fisher-1 trip-1) were constructed as functions of time and distance travelled. Significant nonlinear relationships were found for no. of fish fisher-1 trip-1. Fluctuations in no. of fish fisher-1 trip-1 were strongly influenced by time, while increases in distance travelled predicted a larger no. of fish fisher-1 trip-1. Measures of kg fish fisher-1 trip-1 were tightly linked to increases in distance travelled but did not vary with time. Spatial analysis revealed shifts in areas fished, from inshore reefs during the 1920s and 1930s (pre-WWII) towards isolated offshore island systems in later decades (>1950s; post-WWII). Reported catches pre-WWII were strongly associated with reef species, while reported catches post-WWII were predominantly characterized by demersal coastal fish. Spatially resolved time-series fisheries data can be reconstructed from archival sources, providing valuable information about the development of recreational fishing activities and explaining the historical social-ecological dynamics that led to current ecosystem states.