Affiliations 

  • 1 Centro i~mar, Universidad de Los Lagos, Casilla 557, Puerto Montt, Chile; Centre for Biotechnology and Bioengineering (CeBiB), Universidad de Los Lagos, Casilla 557, Puerto Montt, Chile. Electronic address: patricio.diaz@ulagos.cl
  • 2 Faculty of Marine Environment and Resources, Tokyo University of Marine Science and Technology, 108-8477 Tokyo, Japan; College of Agriculture and Veterinary Science, Department of Integrative Agriculture, United Arab Emirates University, Abu Dhabi, UAE; WorldFish Headquarter, Jalan Batu Maung, Batu Maung, 11960 Bayan Lepas, Pulau Pinang, Malaysia
  • 3 Centro i~mar, Universidad de Los Lagos, Casilla 557, Puerto Montt, Chile; Center for Oceanographic Research COPAS COASTAL, Universidad de Concepción, Chile; Centro de Investigaciones en Ecosistemas de la Patagonia (CIEP), Coyhaique, Chile
  • 4 Centro i~mar, Universidad de Los Lagos, Casilla 557, Puerto Montt, Chile
  • 5 Center for Oceanographic Research COPAS COASTAL, Universidad de Concepción, Chile; Departamento de Ingeniería en Obras Civiles, Facultad de Ingeniería y Ciencias, Universidad de La Frontera, Temuco, Chile
  • 6 Programa de Doctorado en Biología y Ecología Aplicada, Universidad Católica del Norte, Coquimbo, Chile
  • 7 Department of Civil and Environmental Engineering, University of Maine, Orono, ME, USA
  • 8 Centro de Ciencia del Clima y la Resiliencia (CR2), Universidad de Chile, Chile; Departamento de Geofísica, Universidad de Chile, Santiago 8370449, Región Metropolitana, Chile
  • 9 Departamento de Ingeniería Matemática, Universidad de Chile, Santiago, Chile; Centro de Biotecnología y Bioingeniería (CeBiB), Universidad de Chile, Santiago, Chile
  • 10 Facultad de Ciencias del Mar, Departamento de Acuicultura, Universidad Católica del Norte, Coquimbo 1281, Chile; Centro de Investigación y Desarrollo Tecnológico en Algas (CIDTA), Facultad de Ciencias del Mar, Larrondo 1281, Universidad Católica del Norte, Coquimbo, Chile; Center for Ecology and Sustainable Management of Oceanic Islands (ESMOI), Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte, Coquimbo, Chile; Centro de Innovación Acuícola AQUAPACIFICO, Larrondo 1281, Coquimbo, Chile
  • 11 Centro de Investigación en Tecnologías para la Sociedad, Facultad de Ingeniería, Universidad Del Desarrollo, Santiago, Chile
  • 12 @FAN Spa, Puerto Montt, Chile
  • 13 Programa de investigación Pesquera, Instituto de Acuicultura, Universidad Austral de Chile, Los Pinos s/n, Pelluco, Puerto Montt, Chile
  • 14 MOWI Chile, Puerto Montt, Chile
  • 15 Multi X, Av. Cardonal 2501, Puerto Montt, Chile
  • 16 Centro i~mar, Universidad de Los Lagos, Casilla 557, Puerto Montt, Chile; Center for Oceanographic Research COPAS COASTAL, Universidad de Concepción, Chile
  • 17 Bloom Alert Spa, Santiago, Chile
  • 18 Centro Oceanográfico de Vigo, Instituto Español de Oceanografía (IEO-CSIC), Vigo, Spain
Sci Total Environ, 2024 Dec 18;958:178140.
PMID: 39700974 DOI: 10.1016/j.scitotenv.2024.178140

Abstract

Harmful algal blooms (HABs) of toxin-producing microalgae are recurrent in Patagonian fjord systems. Like toxigenic HABs, high-biomass harmful algal blooms (HB-HABs) have important socio-economic repercussions, but most studies have focused on the former. Here we report the formation and development of an intense HB-HAB of Prorocentrum micans that occurred in Northwest Chilean Patagonia in the late summer (February-March) of 2022. Concentrated and extensive brown spots were visible on the water surface, accompanied at the end of February by a strong odour. Prorocentrum micans cells were detected at relatively low densities (up to 215 cells mL-1) in January but by February 11 cell densities exceeded 1000 cells mL-1, reaching a maximum of 8.3 × 103 cell mL-1 in the surface layer. The high cell densities at Reloncaví Sound and the Gulf of Ancud were closely associated with narrow-ranging increases in the sea surface temperature (17-18.5 °C) and salinity (29-31 g kg-1). Sentinel-2 satellite images from February 22 showed a colour change corresponding to the presence of the brown patches at both locations, consistent with the increases in the normalized index of chlorophyll differences (NDCI) and chlorophyll a concentrations (~50 μg L-1). Satellite images from GHRSST indicated warmer waters in Reloncaví Sound and the Gulf of Ancud than in the Gulf of Corcovado, located 170-km to the south. An oceanographic 3-D model (MOSA) showed surface currents with a cyclonic eddy centred in the Gulf of Ancud. This circulation pattern suggested greater water retention in the study area during January and February, with the drifting and rotation of the coastal currents around the eddy maintaining the P. micans bloom. Thus, the elevated cell density of P. micans in the Gulf of Ancud, near the periphery of the eddy, confirm the presence of a material accumulation hotspot for HABs and HB-HABs.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.