What specific feature of the Chinese Goose is susceptible to frostbite when temperatures drop significantly?

Answer

The prominent basal knob on the forehead

Due to their lean build and exposed facial structure, the large basal knob is vulnerable to frostbite when temperatures fall below approximately 20 to 25 degrees Fahrenheit.

What specific feature of the Chinese Goose is susceptible to frostbite when temperatures drop significantly?
whiteChinesebrownbreedgoose