I am not an expert on canaries and there are many different color mutations available. My understanding is that most breeds of canary are monomorphic and there is very little visual distinction between the genders. Gender is distinguished by behavior or DNA testing.
One exception is the mosiac canary. These canaries are not true canaries, but a hybrid of two related species, the Common Canary (
Serinus canaria) and the Red Siskin (
Spinus cucullatus). Red Siskins are dimorphic, with the males showing more color than the female. Breeders crossed these two species and selected for the mosiac color pattern, while breeding back to canaries. From a genetic perspective, most mosiac canaries are predominately canary, but they carry some residual Red Siskin genes, which can show up as more intense color on male mosiac canaries, especially the red or yellow coloring associated with carotenoids.
If your bird was a regular mosiac canary, I would expect it to be white with red or yellow markings. The location and intensity of the markings would indicate the gender of the canary. Mosiacs are usually breed using solid yellow canaries so the markings are not obscured by barring.
However, your bird has additional green/brown markings similar to a wild-type canary. I am not familiar with this type of canary and would double-check with the breeder or seller to find out exactly what kind of canary you have. There are lots of different color-bred canaries available. Knowing the type will help determine if this kind can be visually sexed.
