Is the Ocean Salty Because of Whale Sperm?

Blue whale, artwork
SCIEPRO / Getty Images

According to a viral message, the typical blue whale produces more than 400 gallons of sperm when it ejaculates, a factoid offered up to explain why the ocean is salty. In reality, even the largest whales only ejaculate up to a few gallons of semen at a time, and this ejaculate has nothing to do with the saltiness of the ocean.

The Hoax

This whale sperm myth has been around since 2002, circulating through a chain email that sometimes includes a picture of a sea creature with a large appendage.

FW: Don't drink the sea water... read below first....
The average blue whale produces over 400 gallons of sperm when it ejaculates, but only 10% of that actually makes it into his mate. So 360 gallons are spilled into the ocean every time one unloads, and you wonder why the ocean is so salty...

The Facts

The saltiness of the ocean comes from the erosion of rock, a process that creates electrically charged particles known as ions. Runoff from rivers and streams carries these ions into the ocean, where they accumulate over time. The most common ions in the ocean are sodium and chloride, the components that make up salt.

As for the viral message above, it's a two-part hoax. The text first appeared as a "Fact of the Day" on email joke lists toward the end of 2002, and the image (of unknown origin) began making the rounds in June 2003.

It should be evident at first glance that the text and image don't match. How could the relatively small aquatic specimen in the photo possibly produce 400 gallons of sperm in a single ejaculation? By way of comparison, 400 gallons is about the capacity of a hot tub, meaning this poor creature would have to possess testicles twice the size of its body to live up to its glandular reputation.

A Question of Testicular Volume

Blue whales are the largest animals on the planet. It stands to reason that their reproductive organs ought to be similarly massive, and that is undoubtedly the case. By one estimate, the penis of a blue whale can measure up to 16 feet long, and its testicles weigh in at around 25 pounds each. But even with 50 pounds of bollocks—the weight of an average bulldog—it's absurd to imagine that a blue whale (or any other creature on earth, for that matter) could produce 400 gallons of seminal fluid at a time or even one-tenth of that amount.

The southern right whale, which has testicles larger than the blue whale's, can produce about five gallons of ejaculate in a single mating session. But that's still a far cry from 500.

The statistic in the viral message above is false.

Whale or Whale Shark?

Finally, there's the question of whether the animal depicted in the viral image is even a blue whale at all—which it appears it is not. Blue whales average about 75 feet in length. Using the human beings in the image for scale, the creature is smaller than a blue whale and most likely isn't any kind of whale at all, but rather a whale shark.

Sharks don't actually have penises. The spectacular appendage dangling between the animal's pelvic fins is most likely one of its claspers, a pair of tubular organs with which a male shark fastens itself to the female and inseminates her during reproduction.


  • Helmenstine, Anne Marie. “Why the Sea Is Salty (Yet Most Lakes Are Not).” ThoughtCo, ThoughtCo,
  • “In Pursuit of Giants.” Sunday Times, 22 Sept. 2002.
  • Munro, Peter. “Did You Know?” The Sydney Morning Herald, The Sydney Morning Herald, 30 July 2002,
  • “Whale Sperm Makes the Ocean Salty, Snooki Claims.” Fox News, FOX News Network,