How many times in a minute do fishes open and close their mouth??

Question

Are the timings of opening and closing of the mouth and gill slits coordinated in the same manner???

Answer 1

Freshwater fishes require and use less oxygen and their gill movement rate is about 35-40 times. For Saltwater fishes its about 50.

:-D

Answer 2

I'll answer your second question first - it's easier!

In most cases, the mouth and gill openings are coordinated. A fish opens it's mouth with the gills closed to take in water that contains dissolved oxygen. Then, the fish closes its mouth, and the area surrounding the inside of the mouth (the buccal cavity) contracts and forces the water over the gills as the covers open to extract the oxygen. This is how ventilation occurs. But sometimes (if the need for oxygen is high) fish can keep the mouth and gills open as they swim, and the forward movement pushes the water over the gills - this is called "ram ventilation" (think of this as the fish "ramming" water into it's mouth), but respiration can still take place. The mouth can also work independently while the fish is feeding.

As far as the frequency of ventilation, there are a lot of variables that would determine this. As I mentioned above, sometimes fish don't even open and close the mouth or gill covers, but use their swimming motion. The species of fish will cause differences, because some are adapted to environments with different amounts of oxygen available - some fish have even developed rudimentay lungs, so they can breathe for a limited time out of the water. Within the same species, there will be differences in size/age - smaller fish have a higher ventilation rate than larger ones. There will even be differences within an individual determined by its environment. As previous answerers have noted, temperature plays a big part - warm water increases a fish's metabolism, so it increases the demand for oxygen as well and the respiration rate goes up. At the same time, warm water holds less dissolved oxygen, so the fish needs to respire faster to take in the same amount of oxygen. Some chemicals in the water (pollutants, nitrites, copper, others) interfere with the ability of a fish to get oxygen, so it needs to ventilate more rapidly. Fish will also ventilate more rapidly with an increased activity level (like you breathing harder after climbing a long flight of stairs!), or when stressed or frightened. Lastly, the health of the fish, and presence of gill parasites or excessive slime coat over the gills will affect the ability of a fish to extract oxygen from the water, so the ventilation rate will increase.

Because of all these variables, the ventilation rate in freshwater fish can range from 1 (sustained ram ventilation) to over 100 times per minute.

Answer 3

Around 34 times but it really depends on the water temp.

Vet Tech

Answer 4

depends on where they are, in water about 30-40 times in a min, but when they are out of water not sure.

Answer 5

37 of course.