Not long ago, in response to a spell of insomnia, I learned some of the principles of meditation, to empty my mind piece by piece. It was like the old game of jacks - cautiously lifting each jack clear of its neighbor until only the empty background remained.
Fishing provides that connection with the whole living world. It gives you the opportunity of being totally immersed, turning back into yourself in a good way. A form of meditation, some form of communion with levels of yourself that are deeper than the ordinary self.
At one point I learned transcendental meditation. This was 30-something years ago. It took me back to the way that I naturally was as a child growing up way in the country, rarely seeing people. I was in that state of oneness with creation and it was as if I didn't exist except as a part of everything.
I write until the first draft is finished, and then I feel that I can get out. But, during the time of the writing of the first draft, I don't go out. I'm just locked away, writing. It's a time of meditation, of going into the story.