A slender mola washed up at the research station that I worked at this summer. My buddy juan took this shot. These fish are gorgeous and are a pelagic fish that rarely come up into our temperate waters. This is another sure sign of an El Niño year here in California

They grow to about a meter which is nothing compared to some of the other members of the molidae family. 

This big guy is a Mola mola, also known as an ocean sunfish and they grow to weights over 1000kg! 

You guys might recognize some of the thumbnails and a preview from a post awhile back… here’s the finished piece! :D

Done for the charity artbook Memorieal which recently gave us the go-ahead to upload the illustrations we did earlier this year. As a kid I had a flying/gliding bear species based off this stuffed animal (I named them “Pinky Bears” since I was an original precious snowflake). They were the mortal enemies of eagles, and they primarily ate fish — which they stored underground in burrows. Since that’s what bears do.

Is this one about to grab one or shake its fin? WE MAY NEVER KNOW.


Gone in one gulp! The tiny “by-the-wind-sailors” that have been appearing on area beaches also happen to be a favorite snack of the enormous ocean sunfish (Mola mola), which can grow to be the size of a small car! (photo by Jodi Frediani)

By-the-wind sailors (Velella velella) are actually hydroid polyps—jelly-like invertebrates.The “sail” helps propel the animal on its journey across the ocean. In late spring and early autumn, hundreds of thousands of these drifting sailors wash up on the beaches of Northern California. 

The velella stays on the surface of the open ocean for most of its life. To remain buoyant in the ocean, it has a series of sealed air chambers in its float. They travel in groups of thousands, and capture small fish with short tentacles that have stinging cells dangling underwater. (Although their sting is strong enough to stun a tiny animal, a human being would barely feel it.)

Learn more about the ocean sunfish

Ocean sunfish - Mola mola

The Mola mola is the largest bony fish living today, and only the three largest sharks (the blue shark, basking shark, and great white shark) regularly outweigh this behemoth of the open ocean. 

Like many of the giants of the animal kingdom, the sunfish has a diet that’s almost paradoxically nutrient-poor. All of the calories taken in by adult sunfish are provided by jellyfish and small fry and eggs of other fish, so they spend a large amount of their time eating. Their presence in an area can indicate nutrient-rich waters where endangered species can often be found.

The status of sunfish in the wild is not currently known, though they’re caught often enough that they’re assumed to not be threatened at this point. A multi-year survey of the worldwide sunfish populations is currently underway.

Image: Giant ocean sunfish caught by W.N. McMillan of E. Africa, at Santa Catalina Isl., Cal. April 1st, 1910. Its weight was estimated at 3,500 pounds.


In other news yesterday an ocean sunfish (Mola mola) washed up on a nearby beach and NOBODY WANTED IT so we snatched it and spent the morning dissecting it for science.

Our ocean sunfish was a juvenile male, under three feet in length and with a distinct but underdeveloped testis. Females are slightly (but this is up for debate) larger, and when fully grown, are among the most fecund animals known to man, with some individuals seen to be carrying up to 300 million eggs at a time.

All guts are shifted forwards, to make space for the giant anal and dorsal fin muscles, which move oppositely to propel the fish. They are quite powerful, and can even launch it out of the water like a breaching whale.

Ocean sunfish are also home to upwards of 40 species of parasites at any given time, a picture which I did not include because I care about you. Trust me when I say that if I had that many tapeworms in my liver, that particular organ would not have remained within me for very long. Even if I had to use my bare hands.

Also their caudal fin is completely degenerated through lack of use, and what’s left is called a clavus. Also, as I learned today, is the first thing to become horrifyingly decomposed to a gelatinous liquid after they die.

Anyway, we gave him a decent burial (“decent” is loosely defined here) and in about a year everything but the bones will be gone, after which he’ll be shamelessly exhumed and put on display!


The ocean sunfish, Mola mola, or common mola, is the heaviest known bony fish in the world. It has an average adult weight of 1,000 kg. The species is native to tropical and temperate waters around the globe. The diet of the ocean sunfish consists primarily of various jellyfish. It also consumes salps, squid, crustaceans, small fish, fish larvae, and eel grass. Ocean sunfish are vulnerable to few natural predators, but sea lions, orcas and sharks will consume them.