Hong Kong's Wild Stars

Rodent on the Trees - Pallas's Squirrel

Feb 2020
Author: Green Power
A Pallas's Squirrel Callosciurus erythraeus standing on the tree branch and eating leaf buds
A Pallas's Squirrel enjoying leaf buds.
© Peggy Chung

Cuteness alert! Speaking of rodents, would a fluffy quirky squirrel cross your mind? Pallas's Squirrel (Callosciurus erythraeus) is famous, with its bushy tail and orange-tinted belly. It is de facto a gourmet savvy, who zigzags between branches like a mischievous kid looking for its favourite bites!

Wondering why Pallas's Squirrel loves gnawing nuts and seeds so badly? It has a pair of incisors (i.e. the upper and lower incisors) that grow continuously throughout its life. Hence, chomping harder food becomes the only way to file down its teeth. Yet, no Pallas's Squirrel is a strict vegetarian; they may prey on insects and baby birds to survive. Thanks to the abundant food resources (e.g. leaves, flowers, seeds… etc) provided by the urban trees, Pallas's Squirrel could easily maintain its herbivorous diet here in Hong Kong.

In general, squirrels from higher latitudes cache for winter by stashing food underground. Notwithstanding their hard work, they are too forgetful, letting most of the food eventually sprout in the soil. By contrast, Pallas's Squirrel in Hong Kong would simply finish up their food in one go, all because of the city's mild and warm climate.

Pallas's Squirrel Callosciurus erythraeus going down a tree head-first
Pallas's Squirrel going down a tree head-first.
© Henry Lui

Most squirrels, including Pallas's Squirrel, are tree-dwelling. They are talented climbers of branches and trees. When nesting, Pallas's Squirrels pick higher cavities for better protection. Much to our surprise, Pallas's Squirrel mother customarily spends most of the time looking after the youngsters, very much like to an old Chinese saying: men are breadwinners; women are homemakers.

Imported as a Pet

Pallas's Squirrel is not a local Hong Kong species. Dating back to the 1960s, Pallas's Squirrels were shipped from Southeast Asia. Some of the stray Pallas's Squirrels survived after being released, while some of them escaped during transportation. Owing to the food distribution and threat of predation, Pallas's Squirrels are limited to staying in woodlands in urban areas and the New Territories.

The thai subspecies of Pallas's Squirrel Callosciurus erythraeus on the tree branch
Distributed on Hong Kong Island, the thai subspecies has a paler tail than its counterpart.
© Peggy Chung

By looking attentively at their tails, it is not difficult to distinguish between the paler bellied styani subspecies with an obvious black dot on its tail tip, and the thai subspecies with a lighter tip to the tail. The styani and thai subspecies chiefly settled in the New Territories and Hong Kong Island, respectively.

The styani subspecies of Pallas's Squirrel Callosciurus erythraeus on the tree branch
Distributed in the New Territories, the styani subspecies has a distinctive black dot on its tail.
© Henry Lui

The cuter an animal looks, the more likely it is to be traded. Importing foreign species may pose threats to the ecological balance. This time, we are fortunate to have Pallas's Squirrel as a peaceful foreigner that has so far caused no ecological disaster here. Still, neither releasing animals nor purchasing foreign species should be encouraged. Never try our luck, for the consequences could be catastrophic.