I'm a long time leecher trying to finally contribute =)
First of all, this guide uses the Pool of Blood mechanic in Borean Tundra. You kill an animal to get the 3-minute debuff called "Animal Blood". Then you jump into the nearest deep body of water (Lake Kum'uya in this guide) to create a pool of blood. You can then fish this pool of blood to count for the guild achievement "That's A Lot of Bait" which rewards the recipe for the Cata fish feast. I realize you get junk from these pools, but this method is much more predictable and can be repeated hours on end. I could see that this may be seen as an exploit and I understand Blizzard probably didn't intend this, but as far as I can tell it is working as it should. Thus, I am posting it here. Here is a screen shot of where I do this:
1. Kill an animal to receive the "Animal Blood" debuff (such as a Wooly Mammoth)
2. Jump into a body of water to create a Pool of Blood
3. Fish this pool
Side note: This can be made much much easier by using a bot to kill the animal for you and then fish the pool, rinse and repeat. I use a mac and thus use the Pocket Gnome mac bot. I have this all automated.
This can also be used to fish up the Sea Turtle mount
I can not confirm this myself, but El's Anglin website does say this is true. Here is the link. It is mentioned about half way down.