Spotlight on Oscar the Abalone

My abalone has a first name, it’s O-S-C-A-R….

And although he has no second name–if he did, I bet you can guess what it would be. (At least, those of you over the age of 35.)

Oscar is my abalone (Haliotis sp.). Based on his size when I brought him home (about 1.5″ in length) I’d place his current age around five years (give or take a month or two). He’s more than tripled in size since I acquired him, and although he’s still more active during the evening hours (in the wild, abalones are largely nocturnal), he’s no longer afraid of the light.

For scale, here’s a picture of Oscar during the acclimatization process, when I brought him home in 2012. The snails around him range in size from 1/2″ to 3/4″ in size.

And here’s Oscar now:

16A19 Oscar

Abalones are dioecious, meaning they’re either male or female, and not hermaphroditic (unlike many snails). I’m still not 100% certain that our Oscar isn’t an Oscarina, but (s)he’s staying “Oscar” regardless.

Oscar isn’t a protected or edible variety of abalone. You don’t see many abalones in captive systems (other than large, public aquariums and university programs), mainly because they’re easily bullied (or happily eaten) by crustaceans, fish and other invertebrates. Also, abalones can literally die of fright, so they do best in established reefs with plenty of algae or supplemental feedings. Although Oscar has a shell, but he can’t withdraw into it completely, so like other abalones he depends on camouflage and finding places to hide in the rocks during daylight hours.

Oscar can eat a 3″ x 3″ square of seaweed in less than ten minutes, and I generally feed him 3-4 times a week–more often, if he’s roaming around and looking for food.

16A19 Oscar 2


He’s learned to come to the top of the tank when he’s hungry, because I clip his seaweed to the top of the tank, and he knows to find it there. He’s even smart enough to reach his snout above the top of the water, searching, if he can’t find food at the top of the water. (Which is smart, because seaweed floats, and sometimes he has to feel along the surface to find it.) He doesn’t see well, except for light and shadow, but he has an excellent sense of smell.

When the local reef store has it, I buy him live macroalgae (which looks a lot like seaweed if you don’t know the difference) to give him some variety in his diet. I’ve tried to grow macroalgae in the tank for him, too, but he eats it faster than it can grow, even when I start with enormous clusters. I’ve tried to grow it in plastic mesh bags, so he can only reach the parts that grow enough to emerge from the bags, but he grew frustrated with being able to smell the food he couldn’t reach, so he had to go back to eating seaweed most of the time.

He doesn’t seem to mind.

Have you ever seen a live abalone, in a reef or in the ocean? Do you share my son’s opinion that they look like they belong in a Kleenex rather than a fishtank?