Pacific Roundfin (6 photos)

The Pacific roundfin trout holds a special place in the world of marine fauna. This diminutive fish, rarely exceeding 7 centimeters in length, is often considered one of the ocean's most unusual creatures. The roundfin trout is practically incapable of swimming quickly and maneuverably, making it extremely vulnerable. It can be found throughout the North Pacific Ocean.





Hey, I didn't have that problem until you asked!

Is there a fish more defenseless than the roundfin trout? If so, it's hard to find. Small, no more than 7 centimeters long, this fish is absolutely terrible at everything. Its small, bumpy armor will save it only from particularly biting shrimp, but in return, it ruins the streamlining of its owner, which is already poor due to its odd body shape. With such a set, it's completely unclear how it's supposed to survive.

Just like all other slow-moving creatures: by pretending to be a pebble! In the case of our roundfin, literally. The bumpy plates that replace scales on the fish help it camouflage itself in any uneven landscape, from thickets of marine vegetation and coral reefs to the rocky shores of volcanic islands.



Due to the structure of their armor, dried roundfins look extremely strange.

To avoid revealing themselves by fin movements, the fish did something truly ingenious – it abandoned them. Now its pectoral fins are a large suction cup, which it uses to attach itself to a rock to become not only inconspicuous but also immobile. Needless to say, this hasn't improved its swimming abilities.





Hide by clinging to the glass? Someone miscalculated, I see...



The new fad for nails is scary...

However, the sucker does its job: while the fish sits quietly, it really is extremely difficult to spot. But animals aren't supposed to feed on salt water and sunlight, so sometimes the fish breaks away from its perch and goes hunting: catching things even slower than it. Sessile polychaete worms, slow-moving snails, and small, thin-walled bivalves. And if it's spotted at that moment, it's all over.



Guys, are you sure our camouflage is effective?

No, of course, the roundfin will try to escape, but its attempts at escape look downright comical: the fish darts from side to side, slowly turns around, and quickly runs out of breath. After all, it lacks not only pelvic fins, but also a swim bladder! The roundfin's only hope is to buy a few seconds, during which time a larger fish will find it and gobble it up or scare off the predator that's targeting it!



I will definitely survive...