Weekly Obsession 2023-9-18: Diel vertical migration

Vertical migration of zooplankton in the ocean is something I never knew about until this week! Here’s the wikipedia page about it. This is sooooo coooool

I learned about this from seeing this article about the winners of the ocean photographer of the year award. The winning photo is of this cute paper nautilus. This is a field called blackwater photography which is quickly gaining popularity. This field has really only been around for the past twenty years because you really need autofocus to get good shots of these zooplankton that are so so tiny. Also, digital cameras of the 21st century are far easier to use for underwater photography than film cameras.

So yeah basically the world’s largest regular migration (in terms of biomass) is a daily vertical migration of zooplankton and other underwater animals that rise to the top of the ocean during the nighttime to hunt for food, and fall to the depths below during the day. They’re triggered by the change in light, so sudden migration has been observed during solar eclipses, which is pretty funky fresh.

Also, all these animals routinely bamboozle sonar systems by creating a false ocean floor of sorts. That’s actually how the diel vertical migration phenomenon was re-discovered during WWII. Such a cool story. 

See you next week!

// Callan