Using unmanned aerial vehicles (UAVs) to investigate shark and ray densities in a shallow coral lagoon

Marine Ecology Progress Series

Jeremy J. Kiszka¹  Michael R. Heithaus¹  Kirk Gastrich¹  Johann Mourier¹ 

关键词: Elasmobranchs;    Distribution;    Abundance;    Aerial surveys;    Unmanned aerial drones;   

DOI  :  10.3354/meps11945

学科分类：海洋学与技术

来源: Inter-Research

【 摘 要 】

ABSTRACT: Unmanned aerial vehicles (UAVs) are being increasingly used in studies of marine fauna. Here, we tested the use of a UAV (DJI Phantom II®) to assess fine-scale variation in densities of 2 elasmobranchs (blacktip reef sharks Carcharhinus melanopterus and pink whiprays Himantura fai) on reef systems off Moorea (French Polynesia). We flew parallel transects designed to sample reef habitats (fringing, channel and sandflat habitats) across 2 survey blocks. Block 1 included a shark and ray provisioning site with potentially higher elasmobranch densities, whereas Block 2 most likely had lower densities with no provisioning activities. Across 10 survey days in July 2014, we flew 3 transects (400 m) within each survey block (n = 60 total transect passes). As expected, densities (animals ha^-1) were significantly higher in Block 1 than in Block 2, particularly where provisioning activities occur. Differences between habitats surveyed were also found. Our study provides the first direct estimates of shark and ray densities in coral-reef ecosystems and demonstrates that UAVs can produce important fishery-independent data for elasmobranchs, particularly in shallow-water habitats.

【 授权许可】

Unknown