PT  - JOURNAL ARTICLE
AU  - Vincent Maicher
AU  - Sylvain Delabye
AU  - Mercy Murkwe
AU  - Jiří Doležal
AU  - Jan Altman
AU  - Ishmeal N. Kobe
AU  - Julie Desmist
AU  - Eric B. Fokam
AU  - Tomasz Pyrcz
AU  - Robert Tropek
TI  - Does rainforest biodiversity stand on the shoulders of giants? Effect of disturbances by forest elephants on trees and insects on Mount Cameroon
AID  - 10.1101/2020.06.10.144279
DP  - 2020 Jan 01
TA  - bioRxiv
PG  - 2020.06.10.144279
4099  - http://biorxiv.org/content/early/2020/06/12/2020.06.10.144279.short
4100  - http://biorxiv.org/content/early/2020/06/12/2020.06.10.144279.full
AB  - Natural disturbances are essential for dynamics of tropical rainforests, contributing to their tremendous biodiversity. In the Afrotropical rainforests, megaherbivores have played a key role before their recent decline. Although the influence of savanna elephants on ecosystems has been documented, their close relatives, forest elephants, remain poorly studied. Few decades ago, in the unique ‘natural enclosure experiment’ on Mount Cameroon, West/Central Africa, the rainforests were divided by lava flows which are not crossed by the local population of forest elephants. We assessed communities of trees, butterflies and two ecological guilds of moths in disturbed and undisturbed forests split by the longest lava flow at upland and montane elevations. Altogether, we surveyed 32 forest plots resulting in records of 2,025 trees of 97 species, and 7,853 butterflies and moths of 437 species. The disturbed forests differed in reduced tree density, height, and high canopy cover, and in increased DBH. Forest elephants also decreased tree species richness and altered their composition, probably by selective browsing and foraging. The elephant disturbance also increased species richness of butterflies and had various effects on species richness and composition of all studied insect groups. These changes were most probably caused by disturbance-driven alterations of (micro)habitats and species composition of trees. Moreover, the abandonment of forests by elephants led to local declines of range-restricted butterflies. Therefore, the current appalling decline of forest elephant populations across the Afrotropics most probably causes important changes in rainforest biodiversity and should be reflected by regional conservation authorities.Competing Interest StatementThe authors have declared no competing interest.