Shedd officials don't know how old Granddad is. He was full grown when he arrived in 1933, so he could be 80 years or older. He is now thought to be the oldest living fish in an aquarium in the world. And, he's still healthy.
"At the rate he's outliving everybody I think he could live a lot longer. Probably another fifteen or twenty years. At least I hope," said Bill Gwozdz, who has cared for Granddad for 22 years.
Granddad shares his space with four younger lungfish and a bunch of turtles. He's four feet long, weighs about 25 pounds, and was a gift from the people of Australia 75 years ago. Elizabeth Schick, Australian consul-general to Chicago, was here to honor this endangered creature.
" The aborigines, the indigenous people many, many years ago (ate lungfish). But it's not something you'll see, to my knowledge, something you'll see on restaurant menus in this day an now," said Elizabeth Schick, Australian consul-general to Chicago.
There's no doubt that granddad is one old fish. But he is nothing compared to his great, great, great, great ancestors. These lungfish go back a long, long way.
"The species of lungfish is over 380 million years old. And they haven't changed since they found the fossil records dating back 380 million years," said Gwozdz. " Very successful. I don't think it has any predators in the wild."
One reason lungfish have survived so long is that they can breath fresh air above the water and also use their gills beneath the surface.