The barbel is generally a bottom feeding scavenger with an under slung mouth and is quite
lucky in that other than sight, it has a secondary and third sense of being able to trace food items through smell and the normal 4 barbels/feelers (if that is
what they are for.)
If a mid-water sight feeding fish was to go blind, they would slowly die of starvation.
If the parasite multiplies and attacks lakes inhabitants, it can lead to a wipe out, which has happened in the past.
Even in the River Lea in the 1980's at Fishers Green and King Weir, 76% of the barbel showed similar eye defects that would lead to blindness.
On the River Test, which one would associate to be a prime excellent RQO -1A quality river by the EA, it might just show that things are not as we are led to
believe.
I am sure that you all feel that it is not quite right with barbel going blind as this can happen at a young age.
A precautionary measure in checking fish should be made as eye defects, lesions etc can indicate a decline in water quality and of which barbel are
particularly susceptible and detrimental to the population.
Part of the progression below.
After the cataract effect (which is a colony of white worm parasites inside the back of the eye eating the pupil)
As the eye begins to burst, blood is released
You just don't want to see the rest.







