Microscope reveals diverse life in the St. Croix River

See some of the tiny organisms that live in the river through the eyes of a young photographer.




2 minute read

Via the St. Croix Watershed Research Station:

Algae in a water sample from the St. Croix River, magnified about 200x. (Photo by Aiden T., student from Lee & Rose Warner Nature Center)

When students in a St. Croix Valley nature photography summer camp sat down in front of a microscope last week, they only expected to learn a little about digital microscopic photography.

But one student, Aiden, produced a remarkable image.

The students were taking the class at Warner Nature Center, a summer nature camp in Marine on St. Croix that is part of the Science Museum of Minnesota. One day, the class visited another Science Museum institution: The St. Croix Watershed Research Station, on the banks of the river nearby.

Station scientists had recently collected algae from the St. Croix River, and the students got the chance to use the facility’s inverted microscope to look at the samples magnified up to 400 times actual size.

The magnification revealed the beauty and diversity of life in the St. Croix River water.

In a tiny drop of water, multiple species of algae are shown. There are diatoms — which create glass to form their complex structures — and cyanobacteria, otherwise known as blue-green algae, which are almost always present, but can produce toxins when their population growth is stimulated by nutrients, warm water, and other conditions.

This image is a good reminder that the wildlife of the St. Croix River includes the bald eagles flying above, the fish swimming in the river, mussels on the bottom — and uncounted microscopic organisms.