Well, the interesting question.
in the May month, if the stomach of the fish is bulged that is female, those not bulged are male., Because the Almighty Allah created every living things that he has programmed a lot of things based on several matters of its existence such as breeding time, eating time, sleeping time etc. that automatically functions in every living creatures regardless of they are aware of or unaware of it., as in the case of menustral cycling for female after certain age and once in every month.

There are a lot of things one can learn from fishing., it has many amzing ability to see the underwater, and outerwater alike. They prefer to take food before or just at the time of day break. they sleep like us in the night and depends on the wheather and water they play a lot.

When u buy from market some Sardin fish, u will not find egs in its stomach in other month except in May. During the time when the egs are inside the stomch, the fish is not tasy too. However, I have not experimented several aspect of this pehonomenon based on some region, as well as type of the lifestyle of several fishes known and unknown, but my discovery is based on a general phenomenon identifid.. The morning walker is desingned based on Golden fish moment. you can verify it by checking www.morning walker in google.
I lerant to be patient in all occassion is from fish only, I do on shore fishing for the past 20 years almost and gained lots of practical knowledge about the fish of gulf waters and it is so much interesting. Good luck.