first of all, this makes what you left coasters do, that much more impressive....and i was already impressed
second, do you think this percentage is because of the cvis in general or because you are primarily targeting halis who chill in the surgey areas where it is all stirred up?
there is a lot of plankton,sea snow,microorganisms, etc brought in with the summer current and warmer water.This stuff is great for the baleen whales and other fish who eat it but limits the viz. We also get algae blooms ( like red tide) triggered by a combination of nitrogen runoff and warmer water. Catalina stays clearer because of the current pattern and limited population polluting the water.
We don't primarily target halibut in the summer. White sea bass,yellowtail,albacore,dorado,tuna, and other pelagics are the prime candidates - lurkers under kelp pattties.
Halibut and calico bass are here year round and accessible from shore dives and easier to spot in bad viz conditions.