Movement of moths through riparian reserves within oil palm plantations

Abstract

(250)Tropical forests are increasingly fragmented by conversion to agriculture, with negative consequences for rainforest biodiversity. Dispersal of individuals among the remaining fragments may be critical to allow populations of forest-dependent to persist. In SE Asia, conversion of forests to oil palm agriculture is a particular threat. Many oil-palm dominated landscapes retain forested riparian reserves along streams and rivers, providing potential dispersal corridors to link forest fragments. However the extent to which these riparian reserves are used for dispersal, relative to the oil palm matrix, is poorly understood. We used markrelease-recapture methods to investigate the dispersal behaviour of forest-dependent moths and dung beetles in riparian reserves within oil palm dominated landscapes in Sabah, Malaysian Borneo. We found that moth dispersal was largely unaffected by habitat type and by habitat boundaries, although dispersal distances were significantly higher within riparian reserves than elsewhere. In contrast, dung beetle dispersal responded strongly to habitat type and boundaries.Dung beetles preferentially used riparian reserves to move in and out of forest, and only two dung beetle taxa, Catharsius sp. and O. obscurior, were found to disperse from forest and riparian reserves into oil palm. Dispersal behaviours were not clearly associated with the life history traits of individual species. Our results suggest that, even if riparian reserves are unable to support viable populations of forest-dependent invertebrate species, they may provide valuable dispersal corridors through oil palm plantations, strengthening the case for their retention and reestablishment.

Movement of Moths Through Riparian Reserves Within Oil Palm Plantations

“…We would also like to thank the South East Asian Rainforest Research Partnership (SEARRP), the Stability of Altered Forest Ecosystems (SAFE) project, and research assistants: Lizzie, Loly, Anis, Zul, Sabidi, and Noy. An earlier version of this manuscript was released as a preprint: Gray et al (2018).…”

Riparian buffers act as microclimatic refugia in oil palm landscapes

“…Buffers can also provide co‐benefits for a variety of terrestrial (Barlow et al., 2010; Keir et al., 2015; Zimbres et al., 2017) and aquatic taxa (Cunha & Juen, 2017; Giam et al., 2015). There are also examples of these habitat remnants serving as corridors between other forest areas, promoting connectivity for various taxa (Gray et al., 2019; Keuroghlian & Eaton, 2008).…”