Claire Corlett

Fish Food, Fish Tanks, and More
Why We Sucked At Counting Fish (Until Now)

Why We Sucked At Counting Fish (Until Now)

When Galileo trained his homemade telescope
on the night sky, it transformed from a black pool populated by a few thousand stars into
a sparkling sea filled with ten times the number. And today, with the help of bigger
and better telescopes, we know that our home galaxy – the Milky Way – is an ocean of as
many as 400 billion stars. However, telescopes can’t help us peer into
the watery oceans here on Earth, so to count their inhabitants, we’ve used fish trawls
to drag them up into the light – and then – more often than not – onto our plates.
But now we don’t have to fish fish in order to count fish. In 2010, Spanish researchers
sailed around the world with an ultra high-powered SONAR, shooting sound waves into the depths
and using the reflected signals to spot inhabitants. While previous net counts had given us a global
estimate of about 300 trillion fish, the fish-o-scope method revealed that our oceans are home to
roughly ten times that number. One reason previous counts were so much lower
seems to be that fish actively hide from approaching trawls. In one study, scientists took a SONAR
scan while dragging an open net through the water behind them, and check this out: so
many fish got out of the way that their relative absence highlights the whole path of the trawl.
We don’t know exactly how they manage to avoid the nets, but deep-ocean dwellers like
the fangtooth, lantern fish, and stoplight loosejaw, all of which were especially undercounted
by fish trawls, may take warning cues from their neighbors flashing bioluminescent spots.
Another deep water fish, the finger-sized bristlemouth, turns out to be the most populous
vertebrate on our planet. There are an estimated quadrillion bristlemouths swimming the world’s
oceans. That’s a few thousand fish for every star in the Milky Way.
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100 comments on “Why We Sucked At Counting Fish (Until Now)

  1. HOLY SHIt, my heart nearly jumped out of my mouth when I saw 'Hi, Emily here' in the caption because it showed up before the voice. I was like, HUH? Did YouTube add a feature to find out my name is Emily?? Oh no

  2. I'm… so relieved we're not the most populous vertebrate. I didn't really think we'd be, but it's good to hear it.


  4. And the fact that people still overfish is just gilly. I'd have hoped that they fin-nishd all that nonsense by now. Like come on, people! Cod!

  5. The Lonesome Dove mini-series is also very good. Tommie Lee Jones and Robert Duval are stellar in their roles as Call and Gus.
    Also check out the prequels Dead Man's Walk (About Gus and Calls first adventures as Rangers) and Comanche Moon (About how Call and Gus became legends). Then check out Streets of Laredo (takes place several years after Lonesome Dove). You'll be surprised at who Laurie ended up getting married to.

  6. Oh my goodness we have to stop using bad ways of telling how many fish there are! 🍥 I want to know the real number! 🎏🎐🎣🐟🐠🐡 And not how many are the rare ones left. ↖️

  7. Maybe we should start breeding fish and catching fish when populations are too high! That way we can have enough food, and enough fish to keep the ecosystem healthy. Plus stop making the earth warmer.

  8. Hold up. If there are 3 quadrillion fish, you're saying 1 quadrillion are bristlemouths? So a third of all fish are bristlemouths? Or maybe those don't count as fish?

  9. "A black pool populated by a few thousand stars" – this could only have been written by someone who has never seen the night sky away from city lights. Out in the preindustrial dark, the sky is thick with stars, numberless as sand on the sea shore.

  10. so you mean there are 300 trillion times 10 fish in the water so 3 quadrillion? so you mean 33% of the fish are finger sized? if you know what i mean o_o mhmmm

  11. I'll never buy that fucking cheese! It doesn't matter how much protein there is, I'll never buy it. (Mostly because of the horrendous amount of ads. Stop it)

  12. Omg I accidentally clicked the description and saw when this was uploaded it’s was made on my birthday 🎂

  13. You realize that fish can swim and if you counted them they could have swam to a different spot and be counted again

  14. Net counts had given an estimate of about 300 trillion fish, but the fish-o-scope method revealed that there are roughly ten times it. Now, the estimate is about 3 quadrillion, right? But there is an estimate of about 1 quadrillion bristlemouths, wich means that they alone are 1/3 of all fish in the ocean. Is that right?

  15. This video, amongst many other videos on this channel, have taught me more information in an hour than school has in my entire lifetime and so I'm gonna subscribe

  16. It's an alternative to shallow fishing, it would be a wise move for nations to coordinate an alternating schedule for deep and shallow fishing in an effort to help ease the pressure on existing fish stocks… Just a shame most of the deep sea fish look kinda creepy and don't have much muscle meat compared to other fishes.

    Then again, we only know of about 10% of our planet and 3% of our oceans so you never know, we may find better alternatives through continued exploration…

  17. So you're telling me to fish effectively, I should move My trawl up and down left and right all over for more catch?

  18. When did we start these attempts to count fish by netting them in a trawler, and for how many decades prior had fish populations been subjected to selection pressure for ‘run like bloody hell the second Johnny Human appears’

  19. According to the fish a scope method there are around 3 quadrillion with 1/3 being bristlemouths?

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