First of all, whenever you encountered this, your boat was most likely destroyed. No idea why these things hate rafts/boats or maybe they just simply hate manmade things.
Second of all, why are these things not intelligent enough to tame although the parasaur is near retarded, however you can still tame the freak.
Third of all, I’m pretty sure that the sickle is used for scraping off the meat because not only does it say in the description in the sickle that it can gather fiber, but it also said it’s used for delicately sheering of pieces of prime fish meat (or regular I dunno).
That is all I have to say. Please share if you want people to know more about fishy jerk.