Provided care is taken, the technique of "gloving" make hook removal a forrmality. it should be done with a glove on the left hand (or the right hand if you are lefthanded). You gently slip your finger into the pike's gill opening and your thumb (still on the outside) in a firm grip. The pike may then lifted safely from the water. There is nothing macho about performing this with an unprotected hand, and suffering lacerated or bleeding knuckles from a brush with the pike's toothy gill filaments or secondary teeth on a freezing cold day, belive me - so glove up. Hardware shops stock a variety of suitable gloves.
when you are confident that your left hand (or right hand grip for the lefthanders)grip is sucure, lay the pike on it back on the dampened unhooking mat and slowly curl your hand. The pike has no option then but to open it lower jaw. Then remove the hooks with a long nosed artery forceps from the front, or gently through the opposite gill slit if they are well back in the throat. Even really deeply hooked pike can be unhooked this way (this is why semi-barbless hooks are so good), without the use of the gag or any other type of instrument, most of which can dammmage the fish's dentistry. Forceps between 8 and 12 inches long are ideal, and whatever you do don't be afaid of your pike. Treat it with firm respect.