Effects of Habitat Disturbance can be Subtle Yet Significant: Biodiversity of Hawkmoth-Assemblages (Lepidoptera: Sphingidae) in Southeast-Asia

Abstract

Sphingid biodiversity was compared in a large number of light-trapping samples on Borneo and elsewhere in the Indo-Australian tropics, using our own quantitative light-trapping samples supplemented by other collectors' published and unpublished data. No effects of anthropogenic habitat disturbance on the within-habitat diversity (measured as Fisher's a) were observed, but the faunal composition of assemblages differs significantly under varying degrees of disturbance. Altitude, year of sampling and sampling regime (full night vs. part of the night) were identified as additional parameters that influence the composition of local samples. The frequency of subfamilies in samples varies under different disturbance regimes: Smerinthinae decline along a gradient from primary habitats to heavily disturbed sites, while Macroglossinae show the reverse trend. Connections between the reactions of subfamilies to disturbance and altitude and potential life-history differences between the subfamilies are discussed. Hypothetically, capital breeding Smerinthinae might be commoner and more speciose in stable primary habitats, whereas many income breeding Macroglossinae are probably adapted to thrive in ephemeral, disturbed habitats. Furthermore, we show that estimates from local samples fall short of the total known species richness of Borneo by about 10%.

Determinants of regional species richness: an empirical analysis of the number of hawkmoth species (Lepidoptera: Sphingidae) on the Malesian archipelago

“…1), which could have multiple causes: Sphingidae appear to have their peak of local species richness on Borneo above 1000 m a.s.l. (Schulze, 2000; Beck et al. , 2006), and mountain regions generally have a higher γ ‐diversity due to species turnover along the elevational gradient (for plants, Barthlott et al.…”

“…Smerinthinae may be paraphyletic), this classification has proved suitable for finding ecological differences between major groups (e.g. a preference for undisturbed rain forests in Smerinthinae, but not in Macroglossinae, in Borneo; Beck et al. , 2006).…”

Phylogeny and Biogeography of Hawkmoths (Lepidoptera: Sphingidae): Evidence from Five Nuclear Genes

“…], [ 15], [16]–[21], and biogeography [22]. Sphingids are also a focal group for biodiversity and habitat quality assessment studies [23]. Some species are agricultural pests [24], [25], while others have been used as biological control agents [26].…”

Estimating biodiversity impacts without field surveys: A case study in northern Borneo

“…For the bottom-up methods used in this analysis, an arthropod census must be taxonomically broad, use indiscriminate sampling methods designed to sample arthropods with different habitat preferences, and be drawn from a complete and clearly defined contiguous area. Of the arthropod censuses conducted in Borneo (Kitching et al 2001;Basset et al 2003;Beck et al 2006;Dial et al 2006;Beck and Rüdlinger 2014;Stork 2015, and references therein), we are not aware of any that meet these three criteria. The most comprehensive census of which we are aware that meets these criteria is a survey of lowland tropical forest in the San Lorenzo forest, Panama (Basset et al 2012).…”