Cross-continental comparisons of butterfly assemblages in tropical rainforests: implications for biological monitoring
Article first published online: 10 APR 2012
© 2012 The Authors. Insect Conservation and Diversity © 2012 The Royal Entomological Society
Insect Conservation and Diversity
Volume 6, Issue 3, pages 223–233, May 2013
How to Cite
BASSET, Y., EASTWOOD, R., SAM, L., LOHMAN, D. J., NOVOTNY, V., TREUER, T., MILLER, S. E., WEIBLEN, G. D., PIERCE, N. E., BUNYAVEJCHEWIN, S., SAKCHOOWONG, W., KONGNOO, P. and OSORIO-ARENAS, M. A. (2013), Cross-continental comparisons of butterfly assemblages in tropical rainforests: implications for biological monitoring. Insect Conservation and Diversity, 6: 223–233. doi: 10.1111/j.1752-4598.2012.00205.x
- Issue published online: 22 MAY 2013
- Article first published online: 10 APR 2012
- Accepted 2 March 2012 Editor: Raphael Didham Associate editor: Phil DeVries
- Barro Colorado Island;
- biological monitoring;
- Center for Tropical Forest Science;
- Papua New Guinea;
- Pollard Walks;
- tropical rainforest
Abstract. 1. Standardised transect counts of butterflies in old-growth rainforests in different biogeographical regions are lacking. Such data are needed to mitigate the influence of methodological and environmental factors within and between sites and, ultimately, to discriminate between long-term trends and short-term stochastic changes in abundance and community composition.
2. We compared butterfly assemblages using standardised Pollard Walks in the understory of closed-canopy lowland tropical rainforests across three biogeographical regions: Barro Colorado Island (BCI), Panama; Khao Chong (KHC), Thailand; and Wanang (WAN), Papua New Guinea.
3. The length and duration of transects, their spatial autocorrelation, and number of surveys per year represented important methodological factors that strongly influenced estimates of butterfly abundance. Of these, the effect of spatial autocorrelation was most difficult to mitigate across study sites.
4. Butterfly abundance and faunal composition were best explained by air temperature, elevation, rainfall, wind velocity, and human disturbance at BCI and KHC. In the absence of weather data at WAN, duration of transects and number of forest gaps accounted for most of the explained variance, which was rather low in all cases (<33%).
5. Adequate monitoring of the abundance of common butterflies was achieved at the 50 ha BCI plot, with three observers walking each of 10 transects of 500 m for 30 min each, during each of four surveys per year. These data may be standardised further after removing outliers of temperature and rainfall. Practical procedures are suggested to implement global monitoring of rainforest butterflies with Pollard Walks.