Fruiting phenology and implications of fruit availability in the fragmented Ngele Forest Complex, KwaZulu-Natal, South Africa

- Forest fragmentation can affect fruit availability and quality.
- Fruiting phenology of four mistbelt forest fragments was investigated.
- Numbers of fruiting species per fragment per month were generally low.
- Fruiting was variable and unpredictable between fragments.
- There is a need to conserve a fragment network to provide year round fruit supply for frugivores.

Fragmented forests are under threat worldwide. Understanding fruiting phenology of these is important in terms of food supply to frugivores, particularly avifauna, which can move varying distances between forest fragments. Fragmentation can affect tree species' diversity, which in turn determines fruit availability and quality. Many forest types have predictable, synchronous fruiting which is often linked to climatic cues. However, some forest types show no seasonality in fruiting and have varying fruit outputs between years. We investigated the fruiting phenology of four forest fragments in the Ngele Mistbelt Forest complex, which forms part of the Eastern Mistbelt Forests in KwaZulu-Natal, using fruit-fall traps. We hypothesized that fruit availability would vary with forest fragment size and with season. Fruiting in three of the forest fragments did not show seasonal fruiting trends and had increased fruiting in late summer and autumn months. Middlebrook showed trends. Fruiting varied significantly between months for all fragments, and where annual variation was observed trends were insignificant. The number of fruiting species per fragment varied significantly and numbers of fruiting species per fragment per month were generally low. Tree species varied in their fruiting patterns between fragments and fruiting of Afrocarpus/Podocarpus trees and the implications for endemic, endangered Cape Parrots are discussed as an example. In summary, these forests have variable and unpredictable fruiting between fragments. These results highlight the need to conserve forest fragments of varying sizes as a network to provide a year round supply of fruits to frugivores.