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Updated: Aug 20, 2025

Development of New Methods for Quantifying Fish Density Using Underwater Stereo-video Tools
Published on: November 20, 2017
Targeted census of lionfishes (Scorpaenidae) reveals high densities in their native range
Zara-Louise Cowan1,2,3,4, Rohan M Brooker4,5, Julien Gasc6
1Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway.
Abstract:
Indo-Pacific lionfishes generally exhibit cryptic behaviours and so can be missed when conducting non-targeted surveys. Here, the authors report the results from targeted surveys of lionfish at Moorea, French Polynesia. Lionfish from three species (Pterois antennata, Pterois radiata, Dendrochirus biocellatus) were observed at a mean density of 267 individuals ha-1 . This is substantially higher than previous estimates from the same area (Moorea) and represents the highest reported density of lionfishes from their Pacific range. Overall, this study highlights the importance of targeted survey techniques for detecting cryptic species on coral reefs.
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