Crickets as indicators of ecological succession in tropical

Cricket (Ensifera, Grylloidea) are not commonly used as ecological
indicators in contrary to other Orthoptera (e.g. grasshoppers and
katydids). However, they are sensitive to environmental changes and
abundant in tropical regions. To evaluate if crickets are relevant
bioindicators of tropical ecosystems, we investigated cricket assemblages
along a tropical ecological gradient. We collected crickets during both
day and night in southern New Caledonia for three stages of an ecological
succession: open shrubland, preforest and forest. Simultaneously, we
measured several environmental variables, such as temperature and relative
humidity, at each sampling site. Cricket species assemblages showed a
clear response to ecological succession. The highest and lowest species
richness and abundances of individuals were respectively found in forest
and shrubland, with species specialized in each ecological stage revealing
the conservation value of each of these stages. Similar results were found
when considering only the part of cricket communities with ability to
acoustically communicate. This work is part of a larger research program
about Neocaledonian crickets and contributes to support the use of
acoustic approaches to monitor tropical environments. In conclusion, these
findings highlight the potential value of crickets as an environmental
indicator in tropical ecosystems. The results also contribute to the
discussion of the intrinsic conservational value of shrublands in New
Caledonia and similar ecotypes.