Algae threat easing, but not gone away

Based on available data from the monitoring program and incoming reports, the risk is considered low in production area 3 (PO3) and PO2 at the current time.

For Production area 1 (PO1) in the very south the risk is considered moderate. Monitoring data for PO1 show the presence of Pseudochattonella in some areas, but the density is decreasing and low. Further movement from the inner parts of the Skagerrak cannot be completely ruled out, however.

Farmers in PO1 and outer and central parts of PO2 and outer and southern parts of PO3 have been told they should be aware of the ongoing presence and possibility of local blooms of Pseudochattonella.

The Institute adds: “The Pseudochattonella bloom is still present in PO1. The risk of negative consequences for farmed fish remains high in this area.
 
For PO2, the density varies significantly between stations and the risk is assessed as moderate, also considering the possibility of a spread from PO1. For PO3, there are decreasing densities of Pseudochattonella in the latest round of sampling. For PO3, the risk is considered to be low, but farmers in the southern and outer parts must be extra aware of changes in fish behaviour.

The risk of negative impacts to fish is still considered high in the southern part of PO1, and moderate in the outer parts of PO2 and in the southern and outer parts of PO3. There have been no reports of mortality in any of these areas in recent days.

After a few days of reduced numbers, there are again high densities of Pseudochattonella near Arendal. The IMR said: “There is much evidence that we are registering a new front, most likely originating from the Inner Skagerrak and the Swedish west coast.”