Tom,

I am responding to the whole list to state my concerns to everyone on the
subject of marking fish by injecting chemicals.  Injecting non FDA
approved chemicals into food fish which may be consumed by humans or
other animals should not be done.

There are many approved and successful marking techniques for all
species of fish.

In the case of juvenile salmonids there would be several options.

1.  Partial fin clip (adipose fin, caudal fin, ventral fin)  would be the least
expensive
2.  Coded Wire Tag
3.  Elastomer Tag
4.  VI Jet tag

All of these would be easily recognizable.

If you have any questions you can reply directly to me.

Daniel A. Thompson
Fisheries Biologist
Washington Department of Fish and Widlife
Olympia, Washington
email [log in to unmask]