Bodner, F.; Mahal, S.; Reuter, M. & Fiedler, K. (2010): <b>Feasibility of a combined sampling approach for studying caterpillar assemblages ? a case study from shrubs in the Andean montane forest zone</b>. <i>Journal of Research on the Lepidoptera</i> <b>43</b>, 27-35.
Resource Description
Title:
Feasibility of a combined sampling approach for studying caterpillar assemblages ? a case study from shrubs in the Andean montane forest zone
FOR816dw ID:
922
Publication Date:
2010-12-15
License and Usage Rights:
Resource Owner(s):
Individual:
Florian Bodner
Contact:
email:
florian.bodner <at> gmx.net
1030 Wien
Austria
Individual:
Stefanie Mahal
Contact:
email:
stefaniemahal <at> gmx.de
Individual:
Maren Reuter
Contact:
email:
sandi-mare <at> gmx.de
Individual:
Konrad Fiedler
Contact:
email:
konrad.fiedler <at> univie.ac.at
University of Vienna
Faculty of Life Sciences
Department of Tropical Ecology & Animal Biodiversity
Rennweg 14
A-1030 Vienna, AUSTRIA
1030 Vienna
Austria
Abstract:
We analyzed the suitability of a combined sampling approach ? consisting of visual search<br/>
and branch-beating ? for quantifying tropical caterpillar communities. Surveys were conducted in the<br/>
Ecuadorian montane forest zone, with two shrub species from the genus Piper serving as focal targets.<br/>
We sampled 160 shrubs in the course of four experiments following a standardized sampling protocol.<br/>
Subsequently each shrub was completely defoliated accompanied by an intensive leaf-by-leaf search, in<br/>
an effort to extract as close to 100% of all present caterpillars as possible. We analyzed the resulting<br/>
dataset with regard to completeness, taxonomical bias, and influences of daytime, complexity of shrub<br/>
structure, or experience of the researcher. The standardized sampling protocol extracted between<br/>
50.6% and 71.6% of the caterpillars present on a shrub. A minor taxonomic bias of the sampling<br/>
protocol was observed, but appears to be of a simple and predictable nature, and is therefore easy to<br/>
account for. We did not find any significant influences of daytime. Structure and size of shrubs had<br/>
a strong influence on sampling results with small and simply structured shrubs being sampled most<br/>
completely, large and complex shrubs most incompletely in our dataset. Researcher experience did<br/>
not appear to have an influence on the sampling efficiency or taxonomic composition of samples<br/>
obtained when we compared caterpillars obtained by standardized sampling with those collected by<br/>
exhaustive leaf-by-leaf search. Comparison of caterpillar sizes revealed however, that inexperienced<br/>
field assistants tended to overlook large fractions of the smallest caterpillars entirely. We conclude<br/>
that our standardized combined sampling approach is fairly suitable for studies concerning caterpillar<br/>
communities, especially when resampling of the same shrub individuals is desired.
Additional Infos:
Available online at: http://lepidopteraresearchfoundation.org/journals/43/jrl_43_27_35.pdf
