{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T12:21:19Z","timestamp":1775737279849,"version":"3.50.1"},"reference-count":46,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2019,10,8]],"date-time":"2019-10-08T00:00:00Z","timestamp":1570492800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"New Zealand Ministry for Business Innovation and Employment","award":["UOCX1704"],"award-info":[{"award-number":["UOCX1704"]}]},{"name":"Sustainable Seas National Science Challenge (New Zealand)","award":["C01X1515"],"award-info":[{"award-number":["C01X1515"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Developments in the capabilities and affordability of unmanned aerial vehicles (UAVs) have led to an explosion in their use for a range of ecological and agricultural remote sensing applications. However, the ubiquity of visible light cameras aboard readily available UAVs may be limiting the application of these devices for fine-scale, high taxonomic resolution monitoring. Here we compare the use of RGB and multispectral cameras deployed aboard UAVs for assessing intertidal and shallow subtidal marine macroalgae to a high taxonomic resolution. Our results show that the diverse spectral profiles of marine macroalgae naturally lend themselves to remote sensing and habitat classification. Furthermore, we show that biodiversity assessments, particularly in shallow subtidal habitats, are enhanced using six-band discrete wavelength multispectral sensors (81% accuracy, Cohen\u2019s Kappa) compared to three-band broad channel RGB sensors (79% accuracy, Cohen\u2019s Kappa) for 10 habitat classes. Combining broad band RGB signals and narrow band multispectral sensing further improved the accuracy of classification with a combined accuracy of 90% (Cohen\u2019s Kappa). Despite notable improvements in accuracy with multispectral imaging, RGB sensors were highly capable of broad habitat classification and rivaled multispectral sensors for classifying intertidal habitats. High spatial scale monitoring of turbid exposed rocky reefs presents a unique set of challenges, but the limitations of more traditional methods can be overcome by targeting ideal conditions with UAVs.<\/jats:p>","DOI":"10.3390\/rs11192332","type":"journal-article","created":{"date-parts":[[2019,10,9]],"date-time":"2019-10-09T03:14:33Z","timestamp":1570590873000},"page":"2332","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":60,"title":["Unmanned Aerial Vehicles (UAVs) for Monitoring Macroalgal Biodiversity: Comparison of RGB and Multispectral Imaging Sensors for Biodiversity Assessments"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9153-139X","authenticated-orcid":false,"given":"Leigh","family":"Tait","sequence":"first","affiliation":[{"name":"National Institute of Water and Atmospheric Research, Christchurch 8011, New Zealand"}]},{"given":"Jochen","family":"Bind","sequence":"additional","affiliation":[{"name":"National Institute of Water and Atmospheric Research, Christchurch 8011, New Zealand"}]},{"given":"Hannah","family":"Charan-Dixon","sequence":"additional","affiliation":[{"name":"School of Biological Sciences, University of Canterbury, Christchurch 8041, New Zealand"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2471-6903","authenticated-orcid":false,"given":"Ian","family":"Hawes","sequence":"additional","affiliation":[{"name":"University of Waikato, Hamilton 3216, New Zealand"}]},{"given":"John","family":"Pirker","sequence":"additional","affiliation":[{"name":"School of Biological Sciences, University of Canterbury, Christchurch 8041, New Zealand"}]},{"given":"David","family":"Schiel","sequence":"additional","affiliation":[{"name":"School of Biological Sciences, University of Canterbury, Christchurch 8041, New Zealand"}]}],"member":"1968","published-online":{"date-parts":[[2019,10,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Schiel, D.R., and Foster, M.S. 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