Category: Fish

The Cuttlefish: An Intelligent Cephalopod

Posted on October 9, 2007April 21, 2015 by ellen

Before I visited the Georgia Aquarium, most of what I used to know about cuttlefish included the fact that they can be purchased neatly packaged in dried chewy form in Japanese groceries. So, I was very surprised when I first met one face to face in the Georgia Aquarium and realized they are remarkably intelligent creatures.

Cuttlefish are invariably curious about people, and will come up and try to get a better look if you catch their eye. They are precision swimmers, able to hover motionless near an object of interest by rippling their skirt of fins, only to suddenly jet off in another direction using their funnel siphon when they have seen enough.

Magoo, the world’s smartest goldfish

Posted on May 29, 2006 by ellen

Magoo inspecting the camera.

One of the first fish we ever bought was "Magoo," a little black moor goldfish with big eyes, and loads of personality. We didn’t realize it when we got him, but Magoo was an innovator. Like the famous potato-washing Japanese macaque monkeys, Magoo would invent new behaviors, and teach them to others in the tank.

One characteristic of goldfish as a species is their non-linear thinking. If you ever watch a goldfish try to attain an objective, for instance swimming across the tank to get some food, it may sometimes appear as if the goldfish will forget the goal, then remember, then forget, then remember again, all the way to the other side. They are much more interested in the journey than the goal. In this, Goldfish are the opposite of cichlids, who singlemindedly focus on their agendas better than most people. However this non-linear mental state should not be mistaken for stupidity. Several of our goldfish have been remarkably intelligent. However our orange fantail, Piggum, is not one of them!

Imitation Behavior in Fish

Posted on November 7, 2005 by ellen

One of the more amazing characteristics of fish is their ability to learn by imitation. I’ve noticed imitative behaviors in all of my fish, including goldfish, parrot cichlids, convict cichlids, severums and oscars. Although they come out of the egg already knowing how to swim, how to eat, and how to hide, they add new behaviors as they grow.

Learning attitude: Parrot Cichlids
When young parrot cichlids are put in a tank by themselves, they will usually remain shy for weeks or months. They will hide behind anything they can. If there is nowhere else to hide, they will hover at the top corner of the tank tipping downward slightly, pretending to be part of the filter. However, if they are put into a tank with adult parrot cichlids who have no fear of humans, they get over their shyness very quickly! When we got one of our younger parrots, “Baby,” she immediately adopted the oldest parrot cichlid Winston (a female) as her “mother.” She would follow Winston around, and generally imitate everything she did, and as a result showed very little fear of us.

But most of our newly acquired parrot cichlids spend at least a day or two hiding, during which they peek out from a secure spot to observe what’s going on in the tank.

Experiences with Dropsy in Goldfish

Posted on September 16, 2004 by ellen

Dropsy is one of the worst diseases goldfish can come down with. It’s usually fatal. I hope this description of one goldfish that survived a bout of dropsy will help someone to save their fish.

Fish are said to have the disease “dropsy” when they swell up and their scales stand out all over like a pinecone. As JoAnn the Goldfish Guru says, “Dropsy is a SYMPTOM of other problem(s) with the fish. Dropsy can be due to problems with the environment (water quality, temperature shock, alkalinity), parasites, bacteria or virus.” Dropsy is apparently caused by bacterial infections and kidney failure.

Eggdrop in a happy moment. He has never been able to swim correctly, so he uses the bubblers to get around.

The Story of Eggdrop, Part II

Posted on June 4, 2004 by ellen

“going UP!”

To read Part I, click here

Eggivation!

After he had been back in the goldfish tank a while, I got the idea that changed Eggdrop’s life. I installed a bubbler in the tank to aerate the water at the bottom better, since the tank was pretty tall. One day we looked over at the tank and there was Eggie, shooting up to the top of the tank on a geyser of bubbles.

After watching this for a few weeks, I got another idea – give him MORE bubblers. I put a row of four bubblers across one half of the tank’s back wall. Eggie took to them like he had been born to fly! He would surf from bubbler to bubbler for hours. When tired, he would sink down and go into a flower pot to sleep.

The story of Eggdrop, Part I

Posted on May 22, 2004 by ellen

Eggdrop was born with “flotation-disorder” which means he can’t swim! He rolls around helplessly in the water, sometimes floats near the surface, sometimes sinks to the bottom, and generally has a tough time getting anywhere. His floppy little fins aren’t very strong either – he doesn’t have any reliable means of propulsion or steering.

So how does he get around? It depends on what kind of day it is. If it’s a “sideways” day, he scrabbles about sideways like a crab, using one fin to push along the gravel, and the other for stabilizing, with added boost from shooting water out of his mouth like a squid. If it’s a “headstanding” day, he bounces along on his mouth, like a balloon.

Winning the war on Greenwater Algae

Posted on March 1, 2004 by ellen

For about 4 months, I fought a war against greenwater algae in our big aquarium, home of our pet oscars. If you don’t know what an oscar is, they are the most cantankerous, petulant, opinionated tropical fish ever created and they make great pets. They are members of the cichlid family, and are extremely smart, even trainable.

My oscar, Galadrial, showing her friendlier side

But this article is not about oscars. It’s about their unwanted tankmate: greenwater algae. This algae was so thick I couldn’t even see the fish! They would swim in and out of the green gloom. There are those who will tell you that greenwater algae is good for your fish, and indeed, it may be. But it doesn’t look very good in your living room, and I wanted to be able to see the oscars! So I determined to rid my tank of the ugly, smelly stuff.

This looks a lot like my tank did. Try to imagine 120 gallons of this algae soup in your living room!

photo © Charles Yu, from an FAQ article on algae by George Booth

Glow in the Dark Fish!

Posted on August 5, 2003 by ellen

The Taikong Corp. has created a new fish from the Zebra fish and the DNA of jellyfish. MSNBC article. Model “TK-1”, currently in production, are green, but there will be other colors in the future.