Reading the crown services document raised the interesting aspect of Laminaria hyperborea – the most prominent seaweed on this coast – releasing large amounts of iodine and other chemicals if disturbed – iodine is poisonous to many animals – the compounds are quite complicated, some of them even being capable of affecting the weather.
https://acp.copernicus.org/articles/9/823/2009/acp-9-823-2009.pdf
This is a study of another sea plant but there is no reason to assume that it is not similar to Laminaria hyperborea, it would be interesting to find out if the release of these substances from Laminaria Hyperborea is more vigorous than other seaweeds.
https://asknature.org/strategy/leaves-signal-presence-of-predators/ This is what Acacia trees do – it is not entirely unreasonable to assume that seaweed does the same.
Our maps show the entire coast of Norway where seaweed grows is harvested by trawlers – we don’t have papers on this yet but it is very likely that the harvested/stressed areas send signals to other areas and they too release these chemicals.
