Feeling Rosy!

The head of a rosy rockfish larva.

Hey again! Cherisa here with my next foldscope discovery. As you may recall , I found an amphipod a few weeks back in some seaweed from an intertidal field trip we had taken for graduate school. When I am not busy in classes down at CSU-Monterey Bay, I am busy in Santa Cruz at the National Marine Fisheries Service lab I work at. This lab is home to the Fisheries Ecology Division and lots of really smart scientists! My friend Sabrina studies rosy rockfish (Sebastes rosaceus), which are a smaller type of rockfish, only growing to about 11 inches long. They like to live on deeper reefs, so even though they are bright in color, they live too deep for red light to reach. This makes their red color look more gray and allows these fish to blend in with the shadows and hide from predators!

Rosy Rockfish
An adult rosy rockfish

Rockfish are ovoviviparous, which means they give birth to live young.  Since Sabrina is studying both adult and baby rosy rockfish, we occasionally come in to work and see lots of babies in the tanks! This is called a parturition.  When there are babies, we need to catch them (they are fast!) and count how many there are. Rosy rockfish can have anywhere between 20-50,000 larvae so this is no easy task! The counts allow scientists to make predictions about how many rosy rockfish babies are being born each year, and how the population might be doing.

The backbone of the fish is visible in this image of the tail.

I used my foldscope to try and take some pictures, but it is hard to capture the whole baby fish in my viewing field.  Here you can see the eyes of the fish, and it’s backbone in it’s tail.  Hope you enjoy taking a look!


Two heads are better than one!
Larva tail!
This is what the whole fish looks like under a regular microscope.
This is what the whole fish looks like under a regular microscope.

One Comment Add yours

  1. CarrieB says:

    How cool! Nice work, Cherisa. Was that a two-headed fish, or did you manage to get two fish on your slide?

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