World's Smallest Catch

Oct 15, 2022

This photomicrograph, made at 7X magnification, features the 72 hour embryo of a rainbow trout. This specific hatchery raised a strain known as a 'Tasmanian' rainbow - no reference to Tasmania, but rather for their aggressive nature in striking at lures. Evident is the Blastoderm (cellular mass) atop the yolk sac. Each of the cells of the Blastoderm is genetically identical, and at this stage undifferentiated - essentially these are the fish equivalent of embryonic stem cells.

I have an ongoing project with the South Carolina State hatchery in Walhalla, documenting stages of emnryology in hatchery raised fish. This serves as a visual base against which abnormalities can be compared throughout development. I use such images in my Developmental Biology teaching laboratory.

Meiji Binocular microscope; Motic digital adapter; darkfield and twin fiber optics side illumination.

Find out more details in Behind the Image.

Judges Choice Award - 2022
"I found myself drawn to this image several times during the judging process due to my love of the microscopic world. I always find it fascinating to consider structures and details that most of us do not get to see with our naked eyes. This image is a great example of that and captures a very specific moment, during a very specific event, that could not have been documented without the aid of modern tools. The final product is striking and can inspire endless thoughts related to the unseen portion of the world that we live in".
- Nathan Pallace