Aquatic Critters :: Summer Nature Study - Eva Varga

We’ve been going to Indian Mary near Grants Pass every 4th of July holiday for nearly 15 years now. Each year, I spend a little time picking up the rocks along the shore and investigating the invertebrates that cling to the rocks. The past couple of years, since we are now “homeschoolers” we have gotten a little more scientific about our search and bring along tools for collecting. I hadn’t previously considered documenting our findings until this year.

Searching for aquatic critters is one of our favorite summer activities. The kids spent hours along the river rubbing the rocks to see what critters might fall off into the dish pan. We then carried this back to the campsite where we could sit in comfort of the shade to observe our specimens more closely.

In past years, I’ve always seen a number of dragonfly, mayfly and stonefly nymphs. Planaria worms have also been prevalent.  This year however, I didn’t find a single planaria and instead found numerous midge larva and leaches!  Quite a surprise.

Additionally, we discovered many translucent little gel-like bubbles attached to the rocks as well as a couple of white tissue-like cocoon shapes (shown below).  I am not certain what these are, however.

We pack along a few reference materials with which to identify our discoveries and to learn more about each specimen. Click on this link, A Guide to Aquatic Insects, for a free excerpt from Science Logic: Ecology Explorations.  Using these references, the kiddos and I spend some time sketching and taking notes in our nature journals.

As I shared our discoveries with friends and family with whom we were camping, it was brought to my attention that a notice had been posted near the restrooms that a health concern regarding the portability of the water had been issued due to the water turbidity.  Turbidity is the cloudiness of a liquid caused by individual particles or suspended solids that are generally invisible to the naked eye, similar to smoke in. The measurement of turbidity is a key test of water quality.

Using another key test of water quality, I was delighted that we had determined this for ourselves!