The Science of It!: FISH BUOYANCY

Added: 2026-05-16

[00:00:00]Happy Monday and welcome back to the Orlando Science Center. My name is Mark Medina, joined by Carissa and all throughout the month of May we're actually highlighting physics month here at the Orlando Science Center. And one of the key lessons of physics that we wanted to go over today is buoyancy and how it relates to the creatures behind us, right? Yes. So, fish and sharks kind of do buoyancy a little differently. So, our shark that swims in this tank, he actually maintains his buoyancy by having a very oily liver. Okay. So, like oil floats on the water, they have an oily liver cuz it actually helps them maintain their higher level. So, buoyancy essentially is just an object's ability to float, right?

[00:00:34]>> Yes. Um cuz for most fish species and most shark species, you have to keep swimming to to breathe, to keep pushing the water over their gills.

[00:00:42]So, they need to have a way to stay up in the water column to help them kind of swim around in the tank. Now, for our fish, they do that they don't have that big oily liver, they instead have a swim bladder, which is essentially like a balloon. And that balloon, they can kind of compress as they go down to kind of help shrink out the air so they can go down deeper. But also means that when they're down deeper, when they come up suddenly quickly, that balloon will expand rapidly. Yeah. So, that can be kind of a problem when people are fishing is you want to reel them up slowly or be able to vent that air out for them. Slow and steady wins the race, right?

[00:01:11]>> Yes.

[00:01:12]Um Now, a fish that's not in this tank that kind of does uses their swim bladder also in an addition is our gar. They are found in our swamp tank. Okay. And those gar will actually you'll see them sometimes gulp air. And what they're doing is they're using that to fill their swim bladder. They also use it to breathe oxygen.

[00:01:28]Cuz in swamps tank oxygen levels can kind of go down with droughts and also with algae blooms. Make sense, yep. And so, they will actually use that oxygen in their swim bladder to breathe in addition. Okay. So, they have learned to make that adaptation. So, we learned about so many different ways in which fish and other animals can stay buoyant in the water, but there's so many other key lessons that you guys can learn in relation to physics right here at the Orlando Science Center and I can't wait to see you guys all rather soon.