Assessment of the spatial distribution of Chondria tumulosa, a nuisance macroalga at Manawai in Papahānaumokuākea Marine National Monument using high‐resolution satellite imagery

A red macroalgal species, Chondria tumulosa, has been identified as a nuisance in Papahānaumokuākea Marine National Monument (PMNM), particularly at Manawai (Pearl and Hermes Atoll), where it overgrows native coral and algal communities. This study employed high-resolution satellite imagery from WorldView-2 and -3 to map its spatial distribution across the forereef and backreef over a 12-year period (2010–2021). By analyzing dark patches in time-series animations—first observed in 2015—and validating them against field survey data, researchers achieved an average accuracy of 78% in classifying C. tumulosa using machine learning. The findings highlight the potential of remote sensing for monitoring invasive species in remote marine environments, offering a tool for long-term management and conservation efforts.

Beyer, L., Miura, T., Fraiola, K., Spalding, H. L., Williams, T. M., Martinez, J., Kosaki, R. K., & Lopes, K. H. (2025). Assessment of the spatial distribution of Chondria tumulosa, a nuisance macroalga at Manawai in Papahānaumokuākea Marine National Monument using high‐resolution satellite imagery. Journal of Phycology, 61(3), 722–736. Portico. https://doi.org/10.1111/jpy.70025