When do fish sleep?
There are many kinds of fish, and different kinds of fish sleep times are not consistent, most fish will rest at night, but there are some nocturnal fish that until the night will be active, so will sleep during the day. Because fish do not have eyelids, sleep will not close their eyes, want to determine whether it sleeps, and observe their activities, if long-term in a position, basically do not move, it means that it is sleeping.
What are the habits of fish when they sleep?
1. hide in the water and grass: many fish will hide in the water and grass or stone cracks when they sleep so that they can avoid the attack of some enemy creatures, such as carp, crucian carp, etc. have this characteristic, although the domesticated goldfish after several generations of domestication, this characteristic will still be retained.
2. Hiding in the sand: some benthic fish, usually live at the bottom of the water, when it comes to sleep at night, will also burrow into the sand, so as to avoid being found by other organisms. These fish are mostly marine fish, such as mackerel, fine mimic rondel, etc. are so.
3. Secrete bubbles: Some fish secrete a gelatinous substance when they sleep and wrap themselves up with it. Because this gelatinous material will harden when it meets water, so it can avoid being attacked by other fish, while there are holes in the bubble, it can also facilitate its breathing.
4. Sleeping while swimming: Although many fish will stay still while sleeping, there are some that will keep swimming because they have a special structure and cannot stop swimming or they will die, even while sleeping they will keep swimming.
