That's only half right, you can leave the head in and it's toxic! They now recommend you don't twist them, you need to grip the head with a pair of tweezers, as close to the skin as possible. The plastic pickers I got from the vet, are like mini claw hammers. You slide the claw between the body of the tick and the ferrets skin and slide them untill the head of the tick is as close to the 'V' as possible. It then grips the head of the tick, allowing you to twist & pull in one motion, and the lot comes out, head, mouth parts, the lot. It's always best to remove the ticks as soon as possible,