Seasonality in the equatorial tropics: Flower, fruit, and leaf phenology of montane trees in the highlands of Southwest Uganda

Phenology influences many forest functions and can inform conservation management, yet representative phenological data for most common tropical tree species remain sparse or absent. Between June 2011 December 2013, we investigated flowering, fruiting, leafing patterns in the Bwindi Impenetrable National Park, a montane located near equator Uganda, drawing on 16,410 observations of 530 trees 54 between 2066 2527 m elevation. The park's climate is equatorial with two wet dry seasons each year. Flowering fruiting were strongly seasonal while less pronounced. Flower occurrence peaked at beginning short season followed by pronounced trough during middle season. Fruit had peak high rainfall months March through April fruits ripening drier May July. scarcity was observed 4-month period spanning September to flushing leaves noted end November December. Our binomial generalized linear mixed models indicated that flowering negatively associated temperature activity positively temperature. These findings are consistent insolation- water-limitation hypotheses suggesting seasonally varying availability resources such as light, water, nutrients determines these patterns. Ideally, prolonged, multi-year community-level studies would be supported so better characterize influence variability.