> in at least 44 species<p>That's something quite systemic.<p>Are these fish that use magnetism to navigate? Like sharks do?
There's a solar storm this week. Seems unlikely. Measuring LF EMF
would be a good start. Maybe a HV cable?<p>If it's not a neurotoxin it might be a parasite like
Diplostomum pseudospathaceum that is inter-species and
causes the fish to get eaten more easily [0].<p>[0] <a href="https://www.newscientist.com/article/2129880-parasite-living-inside-fish-eyeball-controls-its-behaviour/" rel="nofollow">https://www.newscientist.com/article/2129880-parasite-living...</a>