Yes, the faux bone handles can be removed. If you try and split them, WEAR EYE PROTECTION. The stuff explodes like a grenade, and sends sharp splinters flying. I mean the sort where the handle is solid, and the knife fixes in to it by way of a tang.
I've never tried, but heating them may be a safer way to do it.
p.s. apologies for wobbling slightly off-topic, but why are those old fashioned fish knives that shape? Just fashion? Or for a purpose? I see them all the time at car boots.