Random questions about Liveships (spoilers Farseer, LST and TM)

[Nuytsia]

* Hints and tips on Ephron and his reasons for not continuing his trading up the Rain River.

Oh another thing, I just read something that indicates Davad thinks the blood plague was linked to the Rain Wilds. I can't recall if it was earlier stated that other people thought that? (Ephron?)

Something I hadn't noticed that I picked up on my re-read was when the serpents moved north they went to colder waters before they got to warmer waters.
This seems weird on the face of it (on our world if you went north you would generally either just get warmer, just get colder, or first get warmer then colder)
But I guess there's always the influencing factors of your 'gulf stream' type flows so who knows. The cold water may just indicate 'open ocean' away from continental influences.

I got the impression that the serpents were in warmer water before they got within the influence of the warm river water coming into the pirate isles area, BUT I think I got that wrong.
I can't find where it's FIRST mentioned (gah!) but it may just be that it's warmer due to those hot rivers ....... so I guess my previous impression was correct! (ie on a world scale it's generally warmer in the south)