The fillets of the fish I cleaned appear “peppered”. What is this caused by and are they safe to eat?
What you are describing sounds like black spot. In black spot, the adult grub lives in a kingfisher’s intestine, depositing eggs that enter the water via the bird’s feces. Upon entering the water, the eggs hatch and the larvae enter the body of a snail. When they mature, the larvae burst out of the body of the snail and swim to the nearest fish. They become encysted in the fins, under the scales and in the meat. The fillets of an infected fish may appear to have been “peppered”. The black pigment is actually provided by the fish. The tiny grub itself is white. This parasite is not a parasite of man. Fish infected with them are edible.
