Does UV radiation kill fish

Answer 1

If the radiation levels are high and the fish is almost always near the surface, UV radiation can cause damage to the skin, leading to infection due to oportunistic bacteria present in water. In nature, this may not happen as UV radiation is reflected to the sky in the hours of maximum radiation (it hits the surface vertically and water acts like a mirror) and fishes do not approach the surface in full daylight (as they protect themselves of being sen by predators). So, in laboratory conditions you can kill fish with UV radiation, but in Nature this would not be so.

A different scenario is worth mentioning for eggs and larvae of fish, these are found in masses near the surface and they lack of protection (pigmented skin) and ability of moving up or down in the water column. This is the case of mayor fisheries species, such as anchovy, herring and sardines and increases in UV radiation can kill a great amount of them. This is the case of all zoplancton, specially in the waters surrounding the South Pole.

Álvaro Aguirre G

Marine Biologist MSc in Oxidative stress and Free radicals