Great Salt Lake

I've been visiting Collin's first grade classroom once a month to teach science. In January, we were learning about water habitats and life cycles. So Collin helped me collect some rock, soil and water samples from two different places at Great Salt Lake (north vs. south arm).

We took the whole family along and drove across the causeway to Antelope Island. We saw antelope, bison, lots of birds, and since it was winter...no brine flies. So the beaches actually looked very beautiful. We threw a boomerang around for awhile. If it hadn't been so cold, we would have stayed longer. But I enjoyed the beautiful drive on a sunny day.

When it came time for science Friday, I brought the Great Salt Lake to the children. We used magnifying glasses to carefully look at the rocks and soil samples. I had caught a few brine shrimp in the water samples. The kids were excited to see them swimming around. Brine shrimp are about the size of your smallest fingernail, and they are the biggest thing that can survive in the lake due to the high salt content.

I taught them about the brine shrimp life cycle, then we got to work on our experiment. Brine shrimp eggs are half seed (as Collin pointed out to me). They can lay dormant for decades and wait to grow until the environmental conditions are just right. So we used a pipette to put hydrated brine shrimp eggs (called cysts) into a Petri dish. Then we put the dishes in different places (garage, closet, refrigerator). We also hydrated some in salt water and some in fresh water.

A couple of days later, I brought in a microscope that hooks up to my laptop. We viewed the tiny shrimp eggs up close. It was neat to see the baby shrimp hatching out of their eggs. We discovered that hatching requires light, heat and saltwater (as opposed to freshwater). It was a great experiment. By the way, shrimp eggs are available at pet stores because people feed them to their saltwater fish. So anyone can do this, you don't have to have access to the lake. Try it!

I also left behind two Winogradsky columns (recycled peanut butter jars) so the kids could grow some microbes from the lake. We put soil and water (from either the north or south arm of the lake) in the jars, and added various microbial food sources (egg shells, newspaper, fertilizer, cheese, plants from the lake, etc.). In a few months, those jars should be filled with colorful microbes. Hopefully the north arm jar will grow different microbes than the south arm jar (and show a color difference).

I told the kids how cool microbes are because they can survive in very extreme environments, places where we humans can not. And they can eat things we can't (metals, sulfur, methane). This is why microbes (and not fish) have found ways to survive in this very salty lake. Cool stuff!