Found this out while mucking about with some mobs.
Works best with the sea creatures called the matayins or greater matayins,they drop between 5-10 pearls,emeralds and skin for bile.

1 swim into the river or sea at a spawn point.

2 aggro the mob/mobs so that they follow you to the shore,engage the mob at melee as this is the only way to pull from the water

3 dont sprint from the mob but just normal run,find the nearest tree/bush large rock and run round it,this bugs/confuses the mob and it stops dead in its tracks,

4 mana missile / shoot with bows ,easy way to lvl your skills also

5 rinse and repeat easy kills/lvling and lots of gold as these items sell for 10-12g each at the vendors

Edit: Lots of spawns around the coast of rubyait...and south of tughri