Inter-annual variability of fruit timing and quantity at Nouragues (French Guiana): insights from hierarchical Bayesian analyses. Supporting data

The timing and quantity of fruit production are major determinants of the
functioning of a forest community, but both components are rarely taken into
account simultaneously. We aimed at determining fruiting variability in timing
and quantity in a rainforest community at two temporal scales: seasonal and
inter-annual. We also examined whether dispersal type may influence fruiting
variation. We developed a hierarchical Bayesian approach for analyzing a ten-
year dataset (2001-2011) of fruit phenology (45 tree and liana species) from
the Amazonian forest of Nouragues (French Guiana), with a 29% of censuses
lacking. Regarding annual seasonality, the fruiting peak of 49% of species was
reached during the peak of the rainy season, which is the most typical pattern
of central and eastern Amazon. Most species varied across years in both timing
and quantity of fruiting, although seed production showed larger changes. We
did not find significant differences in inter-annual variation on fruiting
according to the dispersal mode of species. Parameters extracted from the
Bayesian models were helpful to classify species according to their degree of
variability (low, medium and high) and to distinguish masting events (40% of
species). Seed rain at the community level was dominated by 25% of species,
which overwhelmingly had abiotic dispersal modes (80%). Our analytical method
proved helpful to explore inter-annual variability of the large majority of
species in the community, although showed a poor fit for two continuous
species. It also allowed overcoming the analytical challenge of lacking
censuses, which is a common problem in tropical monitoring. The combination of
long-term monitoring of phenology with sophisticated statistical analyses is
therefore key for a better understanding of temporal changes in fruiting
phenology. Future development of our models will allow forecasting of fruit
variation under new climatic conditions, which has critical consequences for
depending consumers.