A list of curious underwater facts

One: Queen conchs—a type of large sea snail—have a pretty wild sex life. Things get pretty weird when two of them get together: 

Positioned next to a female, shells touching, the male queen conch will extend a long, worm-like penis, also known as a verge, into her shell opening to deliver sperm. This can take many hours. Once they uncouple, the female will eventually lay her eggs on the seafloor in a crescent-shaped sac that looks a bit like dried ramen. 

Oh, yum! But here’s the curious fact: The queen conches are struggling to find mates—due to overfishing in the waters off Florida and the Caribbean. Scientists have stepped in to offer a Tinder-like service—throwing sex parties to help them get it on. Vox has an excellent profile of these goofy creatures. You can admire their beauty in the lead image—and their cute googly eyes below. A related read: We carried an excerpt on the charming and rather complicated love life of land snails from ‘The Harmony of Bees and Other Charms of Creepy Crawlies’ by Ranjit Lal in our weekend Advisory, which you can read here. 

Two: Fishes have fins, octopi have tentacles, but how do scallops swim? Yes, shellfish do swim—by “biting water”. It looks hilariously like this:

So how do they manage this absurd-looking feat?

Scallops draw in water by opening their valves to create a vacuum which draws in water to their sealed mantle cavity. They then rapidly close their valves using their strong adductor muscles to pull them together, which pushes the water back through vents in the rear hinge area, propelling the scallop forward.

But, hey—the queen scallop can move at the speed of over five body lengths per second. That’s three times faster than Michael Phelps! Clamsplaining—as the name suggests—has more nerdy details. Science Direct has historical accounts of scallops swimming—the first of which dates back to 1909.  

Three: Did you know lobster fishers use an innovative method of conserving their catch? It’s called V-notching. Fishers clip a section of the tail of pregnant lobsters—carrying thousands of inky-black eggs. They are called “berried hens”—because they look like this:

The notch is a sign to other fishers to leave them alone. In places like Britain, fishing these lobsters is illegal because—the baby lobsters are very fragile. 

[L]obsters grow relatively slowly.. taking up to seven years to reach maturity. Even though berried hens appear to be crammed with eggs, the chances of their larvae making it to adulthood are exceptionally slim. For the first four weeks, a newborn lobster is less than 1cm in size and is classed as plankton — an easy meal for ocean predators. “In the wild, survival is 0.005%,” says [a technician at the National Lobster Hatchery, Chris] Weston. “That’s maybe one or two of your 20,000 eggs making it to adulthood.”

So it's really a form of enlightened self-interest—at a time when lobster populations are crashing. (The Guardian)