The Porcupine is Canada’s second largest rodent (Beaver is the largest) and can reach weights up to 5.5 kg.
It is estimated that Porcupines have 30,000 quills and as quills fall out or are pulled out, they are replaced with new quills. The porcupine's coat consists of a soft, brown, woolly undercoat and coarse, long guard hairs. These guard hairs are brown at the base and white-tipped in the Eastern populations, whereas they may be yellow-tipped in the Western populations.
If you look closely at the photographs, you will see these guard hairs. However, you do not see any quills. The guard hairs actually conceal the quills until the porcupine is provoked or excited. The quills are longest on the back and on the tail and when the porcupine becomes aroused, the quills will raise up and push the guard hairs forward which results in a crest. The quills have black tips and yellow or white shafts and the end of the quills taper to a fine point at the end, which are covered by dozens of small black barbs. The Porcupine does not have any quills on its muzzle, legs or underparts