sleeping fish

[brads wife]

just sitting here looking at my sons goldfish and was wondering do they sleep???

[andy-hughes]

After a fashion.

They just ... stop in the water and stay motionless, I've never checked for how long though. When i come down in the morning, my goldfishis usually 'sleeping' and as soon as he dectects any movement, he 'wakes up' and starts swimming about as usual.

Because they use their swim bladder to control their depth in the bowl or tank, i guess this must work without effort from the fish, otherwise it would simply float to the top, and appear to be dead, so that's how your know your fish is just asleep, and not passed on.

[hammerman]

They do not sleep as mammals do...fish do not possess eyelids but they do go into a state of trance and become almost comatose.

Obviously some fish are nocturnal but there are many different ways that fish rest at night...some species of wrasse spin a ******* out of mucus to sleep in, some fish dig burrows and then put a shell over their hole....there's many interesting things.

[hammerman]

The blanked out word above was supposed to say c o c c o o n !!!!!!!!