Quote Originally Posted by snakeman View Post
Alan's Garter Snakes - Maintenance of Garter Snakes
I am pretty sure this all started in Europe.
I do not think it's a coincidence that many of these symptoms are the same as mercury poisoning. Even if the fish has fairly low levels, safe enough to eat a couple of meals per month, a diet exclusively of fish would cause it to build up in the snake's system until it becomes toxic.