Interesting...I wonder if large leech species could serve as a good forage base? Sounds like leeches can use fish as hosts, but one of their preferred targets are turtles and frogs and mammals.

http://www.fcps.edu/islandcreekes/ecology/freshwater_leech.htm

Many men go fishing all of their lives without knowing that it is not fish they are after. ~ Henry David Thoreau

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