Squirrel Tails are rare and valuable items and tails to Squirrels.
Conker's Bad Fur Day
In Conker's Bad Fur Day and its remake, when Conker dies for the first time, he will taken to the Underworld and meet Gregg, who tells him that he (and any other squirrel) is a special case, which means he is able to live if he picks up squirrel tails, which give him more chances as he collects more. Conker then collects a squirrel tail hanging on a hook and is then whisked away by an unearthly hand. The tails will not appear until he has met Gregg.
Throughout the game, the rare squirrel tails will be hanging in visible places ready to be collected. sometimes throughout the adventure, there will be "hidden" squirrel tails. These are rarer and more valuable tails can be difficult to find, but they grant a lot more lives than just 1.You can find visible squirrel tails on hooks sometimes. The first squirrel tail is given to you by Gregg, and is worth 1 life.