The Spiny Rodent - East Asian Porcupine
While the name "Hystricidae" may not be familiar to many, the common name "porcupine" would undoubtedly bring to mind the familiar image of the animal covered with long spines. The "porc" in "porcupine" comes from "porcus", which is the Latin word for pig. This might lead to the assumption that porcupines are related to pigs. Taxonomically, however, these animals are more closely related to "rodents". Hong Kong is home to only one species of porcupine – the East Asian Porcupine (Hystrix brachyura). While they are not particularly rare in terms of their distribution and population, observing them can be quite a challenge because they are mostly nocturnal and often shy away from humans!
The global distribution of the East Asian Porcupine is primarily concentrated in central and southern China, as well as several countries in Southeast Asia. Therefore, the inclusion of "East Asian" in its name reflects its global distribution. They are widely distributed and numerous in Hong Kong, apart from their complete absence on the ecologically rich Lantau Island.
A spiny, pungent creature
The East Asian Porcupines have a body length of approximately 60 – 75 centimetres, making it one of the larger mammals in Hong Kong. Their entire body is covered with dark brown fur, and their most distinctive feature is undoubtedly the long, stiff, and hollow spines that cover the rear part of their body. These spines are up to 20 – 23 centimetres long and have distinctive black and white rings that serve both as a defence against predators and as an offensive weapon. When the porcupines are startled, they raise their spines and vibrate them. As the spines are hollow and thin-walled, they make a hissing sound when they vibrate, which can deter approaching threats. If the enemy does not retreat, the porcupines will charge backward towards it and thrust their spines as an attack manoeuvre.
Being nocturnal creatures, the East Asian Porcupines are usually active at night, while they rest in caves or tree hollows during the day. They are herbivores and feed mainly on plant roots and stems, as well as fallen fruits on the ground. Occasionally, they also feed on carrion. They forage in small groups and are often found in forests, grasslands, and agricultural fields. The East Asian Porcupines emit a strong, pungent odour. If you ever venture into the wild at night on an ecological expedition, you can try to detect their presence by smell!
"Pigs" only in name
Taxonomically, the East Asian Porcupine belongs to the family Hystricidae in the order Rodentia, despite its large size, vague resemblance to pigs, and name bearing the word "porc" (pig). Pigs belong to the order Artiodactyla and are not closely related in terms of classification to animals in the order Rodentia. The East Asian Porcupines are actually more closely related to rodents and squirrels, which also belong to the order Rodentia. You could even consider them to be "big rodents" because they have incisor teeth that are sharp and continuously growing, much like rodents!
Speaking of similar-looking animals, people often confuse porcupines with hedgehogs and echidnas because all three of their bodies are covered with long spines. In actuality, however, they are entirely different types of species. Hedgehogs belong to the family Erinaceidae in the order Eulipotyphla; echidnas belong to the family Tachyglossidae in the order Monotremata. Hedgehogs are much smaller than porcupines. They are usually around the size of a palm, and some can be even smaller. They are often kept as pets. Echidnas, on the other hand, fall in between hedgehogs and porcupines in terms of size. Apart from size, you can also distinguish them by their head features: hedgehogs have a relatively pointed face, while echidnas have a prominent, narrow, and elongated snout.
