I didn't see the video, they have taken it down, so if any one has a copy and wants to post it let me know.
But from reading the posts going back and forth on the urchins, I can tell some of your arses must be all puckered up from too much salt water. It's great your are worrying about the environment, but when I see you driving your hybrid car to the beach, taking a row boat over to Catalina, taking a shower to wash out all your gel before getting in the water, and diving without peeing in your wetsuit then I will start to worry about the feeding urchins to the garibaldi.