Death vs. Fishing (thunder/lightning)

Another question:

I was out on the Housatonic this weekend, when some thunder clouds
rolled in. Just as the thunder rumbled, the fish went wild. Every
cast I had a hook up. The clouds moved in further, lightning flashed
in the distance. All the other fisherman left the water. Finally, I
did too. Though, man, was it hard to leave those leaping browns.

My question: does anyone actually know just how dangerous it is to be
fishing - standing in the river - when there's thunder and lightning?

I'm not talking about situations where lightning's striking constantly,
visibly touching ground in close proximity to you, rain in sheets, the
really scary/exciting kind of storms. It seems fairly obvious that
it's not a good idea to stand around anywhere outside during those kind
of storms. I'm talking more about, maybe a lightning flash once a
minute, some thunder rumbling, maybe some of it loud, some rain coming
down. But not, if you weren't standing in a body of water, something
you'd be concerned about.

Another part of this question: in the Housatonic, at least, the river
is the lowest point around. There are hills all around that seem much
more likely to attract lightning. Unless if the combination of
water-conductivity and you standing in said water holding a 9' graphite
pole trumps the fact that you're standing in a low area.

I'd love any scientific, accurate, knowledgeable answers and/or links.
Though I'll accept people just adding their .02, sharing what they do
in these situations, based on fear, wives tales, whatever...