Title: Regional suitability assessment for marine cage culture of canary drum (Umbrina canariensis) along the Angolan coastline

Abstract

August Magalhaes´ final project will be published in due time. Until then we share the abstract and a link to a poster.

This study evaluated water quality and oceanographic conditions across Angola's Northern, Central, and Southern coastal regions to identify optimal sites for sustainable marine cage aquaculture of Umbrina canariensis (Canary drum). Seasonal data were collected during research cruises in 2017, 2019, 2022, 2023, and 2024 aboard the Norwegian research vessel, Dr. Fridtjof Nansen. A Seabird 911+ CTD probe was used to measure vertical profiles of temperature, salinity, and dissolved oxygen, and a Chelsea Mk III Aquatracka fluorometer was used to assess chlorophyll-a concentrations. The results indicated that the Northern and Central regions offer favourable conditions, with sea surface temperatures ranging from 17–26°C, stable salinity, and sufficient dissolved oxygen levels in the upper 5–30 meters of the water column, supporting viable sea cage farming. In contrast, the southern region exhibited lower and more variable temperatures (14.58–17.67°C), which may negatively affect the growth and metabolic performance of the species. Elevated phytoplankton biomass in the northern region was found to enhance surface oxygen through photosynthesis but also contributed to subsurface hypoxia due to organic matter decomposition. Based on these findings, the Northern and Central regions are recommended as more suitable for U. canariensis aquaculture. This study emphasises the importance of continuous environmental monitoring to ensure the long-term viability and sustainability of cage farming operations.