Mike,
As a graduate student at Hokkaido University in Japan, I had the
opportunity to interact with students of many fisheries disciplines.  I
recall discussing a clever marking technique involving the Pacific saury
(I don't know the latin name) and rubber ring tags.  This species
(evidentally) has an inclination to swim through small rubber rings
broadcast from vessel decks.  The fish is long and slender, and many
fish could be tagged rather easily.

I've read several responses from others on this topic, and I have to
wonder if some fish may have a curiosity that compells them to swim into
a rubber band.
--
Best regards,
Brian Bigler <[log in to unmask]>
Lynnwood, Washington
           USA