Image: El Ciudadano / FIS
Another salmonids mass mortality in the Seno de Reloncaví due to harmful algal blooms
Wednesday, November 29, 2023, 01:00 (GMT + 9)
The National Fisheries and Aquaculture Service (Sernapesca) of the Los Lagos region reported on a new mass mortality event in the Seno de Reloncaví, but this time in the Group of Salmonid Concessions (ACS) No. 2, an area that until Last week it had only activated its action plans for Harmful Algal Blooms (HAB) due to high concentrations of the microalgae Thalassiosira pseudonana.
According to the information provided by the supervisory entity, in ACS N°2 there are 28 active farming centers with a total biomass (live fish) of 49,727 tons. Of the total centers, 11 have activated their action plans for HAB and 2 of them have activated their action plans for Mass Mortality.
“The mortality recorded as of today, Monday, November 27, is 913.5 tons. As always, we have been supervising compliance with the contingency plans of the affected companies and the withdrawal of mortality that the companies themselves must do. The mortality is being removed in its entirety and 898.8 tons have already been taken for final disposal to reduction plants. We will maintain surveillance in this and the surrounding ACS, since the centers in these areas continue to report daily the presence of the microalgae and irregular behavior of the fish, which represents a sign of attention for our service," commented Cristian Hudson, Regional Director of Sernapesca Los Lagos.
Harmful Algal Blooms are a natural phenomenon caused by multiple climatic and environmental factors, generating a numerical increase of one or more species of microalgae in the water. Specifically, the microalgae Thalassiosira pseudonana lodges in the gills of fish, causing internal damage and causing death by suffocation. It should be noted that this microalgae does not correspond to the so-called “red tide”, so bivalve mollusks or other fish are not affected.
Source: Sernapesca (Translated from the original in Spanish)