Q.
Can trout re-grow
the slime/mucous layer that fishermen often wipe
off with dry hands or poor quality nets?
A.
Yes, the mucous is secreted from living cells
and can be replaced.
This mucous layer serves the fish three ways:
(1) as a lubricant to aid passage through the
water, (2) to protect the skin from bacteria,
fungi, or other parasitic organisms, and (3)
to keep the fish “water-tight” and help control
movement of chemicals through the skin.
Incidentally, the effect of removal of the slime
by anglers is controversial. One test, using
trout caught with flies, separated half of them
handled with wet hands and half with dry hands;
survival was no different between the two groups.
It is thought by some that greater removal of
slime by handling with dry hands was counterbalanced
by the fact that these fish were more easily handled
and returned to the water quicker and with less trauma.
~ Bert
If you have a question, please feel free to contact me.
~ C. E. (Bert) Cushing, aka Streamdoctor
105 W. Cherokee Dr.
Estes Park, CO 80517
Phone: 970-577-1584
Email: streamdoctor@aol.com
The ‘Stream Doctor’ is a retired professional stream ecologist and
author, now living in the West and spending way too much time
fly-fishing. You are invited to submit questions relating to
anything stream related directly to him for use in this Q & A Feature
at streamdoctor@aol.com.
Originally published May 16, 2005 on Fly Anglers Online by Bert.