Got to see an early cut when I was down there earlier this year. There's some really interesting stuff about brown trout migration and feeding from fish biologist Rasmus Gabrielsson (NZ fish & game). They move a lot during their life, sometimes as they get larger taking up residency where young trout can't prosper like areas prone to flooding, occasionally even skipping spawns to keep condition. He gave a presentation at their FFF conclave down there discussing how he mapped waters based on mineral content, then studied oteliths (sp? the ear bones) to build up life histories. Some of the info on searuns was akin to steelhead deciding to stay in the river. Fish are amazing
