Species richness measures fail in resolving diversity patterns of speciose forest moth assemblages
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We used data from a light-trapping study at 28 sites on floodplain forest moths in eastern Austria to assess the performance of a variety of species richness and species diversity measures. At each site the data (32,181 individuals from 448 species) contain a large fraction of species represented only as singletons. Sampling effort was evenly spread across sites, but sampling success varied greatly. Influx of moths from the landscape matrix surrounding floodplain forest patches lead to substantial proportions of stray individuals from the regional species pool. Under these conditions, observed species numbers as well as eight extrapolation estimators of species totals failed to reflect differences between three study regions or between flooded and non-flooded forest habitats. Rarefied species numbers and Fisher’s α of the log-series distribution captured differences in moth diversity between regions, but failed to mirror flooding impact. Only Shannon’s diversity captured all expected diversity differences, at high significance levels. Application of Chao and Shen’s bias correction increased figures of Shannon’s diversity, but did not affect the outcome of statistical comparisons. We conclude that for species-rich incompletely sampled communities of highly mobile insects the evaluation of the complete species-abundance information using Shannon’s diversity is the most promising mode to compare local species diversity with a high degree of ecological resolution. Species richness measures apart from those obtained through rarefaction cannot be recommended, as they are sensitive to sources of bias that pertain to many empirical sets of field data.
KeywordsDiversity indexes Shannon’s diversity Fisher’s alpha Species richness estimators Sampling effects Ecological resolution
We thank Florian Bodner, Jan Beck, Gunnar Brehm and two anonymous reviewers for helpful comments on an earlier manuscript draft. Ottokar Jindrich (Austrian Armed Forces), Gerhard Neuhauser (WWF), Christian Baumgartner (Nationalpark Donau-Auen) and Peter Jansen (Harrach’sche Forstverwaltung) kindly granted access to study sites.
- Anderson MJ, Gorley RN, Clarke KR (2006) PERMANOVA+ for PRIMER: guide to software and statistical methods. Primer-E Ltd., PlymouthGoogle Scholar
- Beck J, Schulze CH, Linsenmair KE, Fiedler K (2002) From forest to farmland: diversity of geometrid moths along two habitat gradients on Borneo. J Trop Ecol 18:33–51Google Scholar
- Chao A, Shen TJ (2009) SPADE (species prediction and diversity estimation). http://chao.stat.nthu.edu.tw. Accessed 04 Nov 2011
- Clarke KR, Gorley RN (2006) Primer v6: user manual/tutorial. Primer-E Ltd., PlymouthGoogle Scholar
- Colwell RK (2009) EstimateS: statistical estimation of species richness and shared species from samples. Version 8.2. User’s guide and application. http://viceroy.eeb.uconn.edu/estimates. Accessed 01 Oct 2011
- Fiedler K, Schulze CH (2004) Forest modification affects diversity (but not dynamics) of speciose tropical pyraloid moth communities. Biotropica 36:615–627Google Scholar
- Lazowski W (1997) Auen in Österreich: Vegetation, Landschaft und Naturschutz. Monographien 81. Umweltbundesamt. Federal Environment Agency, ViennaGoogle Scholar
- Thomas AW, Thomas GM (1994) Sampling strategies for estimating moth species diversity using a light trap in a northeastern softwood forest. J Lepid Soc 48:85–105Google Scholar
- Truxa C, Fiedler K (2012) Down in the flood? How moth communities are shaped in temperate floodplain forests. Insect Conserv Divers 5. doi:10.1111/j.1752-4598.2011.00177.x