Saturday, May 26, 2007

Flounder Fascination

I am a fishophile the way many of you are birdophiles. If this were some kind of competition I would point out how my clan (fish) are the most varied of vertebrates ... way more species than all the other stiffback clans together. I might point out that by percent of body weight, fish are the most muscular of vertebrates and I could even point to the fact that they were here a gadzillion years before our feathered friends.

That's a lot of pointing.

If I were not tired of pointing out the extreme coolness of fish, I might just point to the flounder and sit back smugly with my fins folded across my chest.

Consider the flounder. He's a compressed (flattened side to side) fish. Nothing weird about that, but the flounder is a bottom dweller (demersal) and lies flat on the bottom. Not on his belly, but on his side.

The side he lies upon is lacking in the chromatophores that allow him to change color and pattern to match the bottom. It's also lacking in eyes since that would be pretty dumb to have an eye staring into the muddy bottom.

As you probably already know, flounders are born with normal eye position, but while still very young, the eye on the bottom side migrates to the topside. The flounder in the picture is so young and semitransparent that you can see into his skull. His eye has already migrated and it LOOKS like you can see the channel it traveled. I'm not sure if that is accurate, but it sure looks that way.

What you can't see in that photo, because they are so tiny, is the dagger like teeth this very aggressive predator is toting in his mouth. Flounder are ambush predators of their fellow fish and other small animals and they need long sharp teeth to hold their struggling prey.

If you are careless getting the hook out of a flounder's mouth, you will always remember the pain. I do.

In fact, I've had to remember it a couple of times.

The young flounder in these photos is a Gulf Flounder. The triangular pattern of 3 large ringed dots makes the Gulf Flounder an easy ID. They don't get as big as the Southern Flounder, but they are just as tastey.
Flounder change color to match the bottom pattern so a fresh caught flounder tells you what the seafloor below is like. They change color and pattern by enlarging or shrinking pigment cells called chromatophores. Picture one of those tiny umbrellas you get in a girly drink. Viewed from the top, if you open it you see a large circle of color, close it and you see a small circle of color. Chromatophores work like that.
Flounder fishing is an art. The bite is not sudden or jarring. It's a gentle tightening of the line, a slight bump, then steady pressure. You have to let Mr. Flattie take the bait for a bit before setting the hook. Premature hookulation will result in a missed fish.
The flounder is my very favorite fish to eat, but I admire them for what they are also. It's not just a tastebud thing. They are an amazing predator and ... I think they are quite beautiful.
Yesterday I released the little flounders from my classroom aquariums at the boat ramp near the Marine Research center out at Cedar Key.
I hope to see them again someday.
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threecollie said...

I just know we are going to learn something here. And never having seen the underside of a flounder, all I can say is cool!

Floridacracker said...

You farmers are such early birds. You beat the post!

pablo said...

Okay, Mr. Smartypants! If flounders don't have eyes looking into the mud, how do they know what color to change to in order to match the bottom? Got you on that one, didn't I?

I saw one in the Carribean once that was on sand, and I recall that it sort of nestled inself into the sand some to get more protection. If I hadn't see it do that, I wouldn't have been able to recognize it even though it was right before me.

Paintsmh said...

All I can say is, I want fish dinner. And its only 10:40!

robin andrea said...

I thought this was going to be a post about your dog!

Great info about the flounder. I really had no idea how cool this little critter is. I have new respect.

rcwbiologist said...

Another informative post. Thanks again for lesson. "Premature hookulation", that is classic FC, love it, and its one of the reasons I keep coming back to read your posts.

Cathy said...

It's so great that you take the time to explain all this wonder. Very cool. Your students are so lucky.

rick said...

Stuart went gigging last week and got 9 we are going tomarrow night.When he was out the other night a porpose was throwing red fish in the AIR AND catching them before they hit the water

SophieMae said...

I do love flounder, but I might just like grouper a tad bit more. Hmmmm..... I think a taste test is in order. Ever try monkfish? Ugly creatures, but they taste like lobster.

vicki said...

I prefer that other cross-eyed wonder: halibut. To eat that is- they are ugly as sin but these flounder are not half bad looking. I do love your baby photos, too, esp. that little crabby one.

LauraHinNJ said...

I never knew any of this about flounder - I ought to know something as they're the only fish I like to eat.

I'd be interested if you'd answer Pablo's question.

SophieMae said...

PS - Mashes Sand is the beach at the end of Mashes Island where Apalachee Bay and Ochlockonee Bay meet. Right across from Bald Point.

Floridacracker said...

Well, as you know, fish eyes tend to bulge out a bit and flounder eyes literally sit up above the skin. With that excellent wide angle view, they can easily see the bottom. You're right about that sand fluffing, it really hides their outline.

It's 5 O'clock somewhere :)

Extra points for thinking of my sweet Flounder dog!

I admit, I enjoyed that one too.

Ahhh, the wonder of the internet. Now I can bore people outside my classroom :)

Stuart's got the gigging gene from his Grandpa. I watched a dolphin do that with mullet in Salt Run years ago.

Flounder and grouper are close and I'd toss in whiting fresh from the beach as a match to either one. Haven't tried monk yet. I figured Mashes to be in that zone. Haven't been there tho.

See above, but it's a simple matter of wide angle eyes that are elevated and independently moved. Their little fishy brain takes in the data and adjusts the chromatophores.