Abstract
Passive acoustic methods are increasingly used in biodiversity research
and monitoring programs because they are cost-effective and permit the
collection of large datasets. However, the accuracy of the results
depends on the bioacoustic characteristics of the focal taxa and their
habitat use. In particular, this applies to bats which exhibit distinct
activity patterns in three-dimensionally structured habitats such as
forests. We assessed the performance of 21 acoustic sampling schemes
with three temporal sampling patterns and seven sampling designs.
Acoustic sampling was performed in 32 forest plots, each containing
three microhabitats: forest ground, canopy, and forest gap. We compared
bat activity, species richness, and sampling effort using species
accumulation curves fitted with the clench equation. In addition, we
estimated the sampling costs to undertake the best sampling schemes. We
recorded a total of 145,433 echolocation call sequences of 16 bat
species. Our results indicated that to generate the best outcome, it was
necessary to sample all three microhabitats of a given forest location
simultaneously throughout the entire night. Sampling only the forest
gaps and the forest ground simultaneously was the second best choice and
proved to be a viable alternative when the number of available
detectors is limited. When assessing bat species richness at the 1-km2
scale, the implementation of these sampling schemes at three to four
forest locations yielded highest labor cost-benefit ratios but
increasing equipment costs. Our study illustrates that multiple passive
acoustic sampling schemes require testing based on the target taxa and
habitat complexity and should be performed with reference to
cost-benefit ratios. Choosing a standardized and replicated sampling
scheme is particularly important to optimize the level of precision in
inventories, especially when rare or elusive species are expected.
Original language | English |
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Pages (from-to) | 4690-4700 |
Number of pages | 11 |
Journal | Ecology and Evolution |
Volume | 4 |
Issue number | 24 |
Early online date | 2 Dec 2014 |
DOIs | |
Publication status | Published - Dec 2014 |
Keywords
- bat activity
- cost-effectiveness
- echolocation
- forest microhabitats
- inventory
- species richness