Why Do Skunks Smell So Badly?

Because they have developed the ability to spray large amounts of musky stuff at possible dangers.  It puts their would-be predators off; only one north American species regularly preys on them.

Skunks are small waddly creatures.  They have musk glands on different parts of their bodies, particularly around the anus.  When they are distressed, threatened or suddenly frightened, they instinctively spray the musk out their bottoms. The spray chemical is comprised of thiols -- sulphur and hydrogen compounds.

Skunks typically they do a warning routine before spraying.  They dance, lift their tails, turn bottom towards you.  And sometimes stand on front legs, before finally letting loose.

You can see why some dog owners despair of how dumb their animals are to be getting repeatedly sprayed.

The other thing about skunk smell is not only is it unpleasant, strong and persistant -- it's also rather hard to get rid of and rubs off of one thing and onto others.  The classic remedy is a bath in tomato juice.  The modern thinking is that the best remedy is a bath in a foamy oxidising solutions made up of liquid soap, Sodium Bicarb and Hydrogen Peroxide.