How do you interperate this?

http://www.dfw.state.or.us/fish/docs/2009_oregon_sport_fishing_regs.pdf

Marine Zone
Regulations for this zone:
(skiping down to line item #10)

10. It is unlawful: for anglers fishing from a boat to mutilate fish so the size or species cannot be determined prior to landing; to transport mutilated fish across state waters; and for anglers fishing from shore to mutilate fish so that size or species cannot be determined prior to reaching their automobile or principle means of land transportation, and having completed their daily angling. This does not apply to herring, anchovy, smelt and sardine

After reading this, what are your thoughts on using a retained kelp greenling as bait for fishing Lingcod?  I've read somewhere people do this, but also rightfully count that greenling in their daily catch limit.   If said greenling is snatched in half by a big ling that gets away, would that not be considered mutilation?   Do you just drop the remaining green ling bits overboard to feed the birds, pinnipeds, etc.. yet still count it in your bag limit?   What would be the right thing to do from "your" point of view. 

my view....catch the Ling.

More than likely the greenling will not have been mutilated.  In fact, it is highly likely it will still be alive and kicking.  Send it back down and catch another.  I've used the same greenling bait to catch multiple lings, then proceeded to eat the greenling for dinner.   

-Allen

More than likely the greenling will not have been mutilated.  In fact, it is highly likely it will still be alive and kicking.  Send it back down and catch another.  I've used the same greenling bait to catch multiple lings, then proceeded to eat the greenling for dinner.   

-Allen

 
Having to go back down and face another toothy monster over and over, has got to be traumatizing.   
That greenling was wishing you would just kill it already! 

The lings have the wrong teeth and jaw structure to tear a greenling in half. They just swallow their prey whole.

greenling has a ten inch minumum length for retention, so does this mean it has to be ten inches or bigger to use as bait?

It technically has to be 10" to use as bait.  Just send the undersized ones back down before you have a chance to land them (i.e. take them out of the water).  I don't think it's bait until you actually land it and pin it onto a bait hook.

bsteves is right, a kelp greenling needs to be 10" to be retained.

The one thing that's not mentioned here is that if you catch the greenling the same day you use it for bait it counts against your daily limit of rockfish.