Oceanographical Context of the First Bloom of the Silicoflagellate Octactis speculum (Ehrenberg) Recorded to Cause Salmon Mortality in a Galician Ria: Was This Bloom a Rare Event in the Iberian Coast?

ABSTRACT: Harmful algal blooms are one of the leading causes of mortality in salmon aquaculture, with significant economic consequences. From 15 to 31 October 1996, a bloom of the skeletonized form of Octactis speculum (Ehrenberg) F.H. Chang, J.M. Grieve & J.E. Sutherland was detected in the small Merexo inlet (1.7 km² area), located on the southern shore of the Ria of Muxía (Galicia, NW Spain). The O. speculum population inside the inlet (data period: 1992-1996) seldom exceeded 4·10³ cell·L^-1. However, its concentration reached 2·10⁵ cell·L^-1 during the bloom, coinciding with a decrease in light penetration from 5 to 2 m deep, as measured using a Secchi disk. Although similar concentrations were reported during late October 1992,

SUBMITTER: Prego R 

PROVIDER: S-EPMC10467100 | biostudies-literature | 2023 Jul

REPOSITORIES: biostudies-literature