I noticed my dog’s nose has lost fur and has black spots; what is this?

A dog’s bald nose with black spots may be melanin deposition, where irregular dark patches appear with age, like human age spots, which is normal. Also, insufficient or unbalanced nutrition can cause local hair loss.

But if the bald area has dandruff, discharge, or red surrounding skin, it may be a skin disease; take the dog to a hospital to identify the type and treat accordingly.