How to distinguish a female from a male Danio

It should be noted right away that sexual dimorphism in Danio fish is weakly expressed. Males and females, especially at a young age, are almost identical. However, there are several indirect signs that help determine the sex of the fish.

The size. Females look larger than males, and their abdomen is usually more “chubby”, which is especially noticeable when viewed from above. Males are slender, “thin”. Differences in size are noticeable during the breeding season, when females fill with eggs.

Coloring. Males are colored a little brighter, the body pattern is more contrasting (side stripes, spots etc.). The females appear to be somewhat faded.

Behavior. Males are more active, which is clearly manifested during the mating season, when they circle around females with straightened fins.

These signs are characteristic of all Danio species, including hybrid varieties. However, it is very difficult to see them. из-за high mobility of fish. And in some cases, even an experienced aquarist will not be able to determine the sex. For example, in the image below, it is unlikely that males can be distinguished from females.

It is important to remember the following nuances:

 Compared fish should be sexually mature, about the same age. All fry and juveniles look the same;

 The diet should be balanced, food should be served regularly. It is problematic to identify the sex of emaciated fish.