Annual State of Lousignont Creek Report – December 2021
Over the past nine school years the 7th grade class of Catlin Gabel School has embarked on the important (often wet, cold, and muddy) work of assessing the water quality of Lousignont Creek as it flows though Hyla Woods on its way to the Pacific. Students learn the ways of the field scientist and work as team members at one of twelve field sites along the creek. Hand-in-hand, they investigate the stories of and tensions between forestry and conservation here in the Pacific Northwest, with special attention paid toward the threatened Oregon Coast Coho salmon. To wrap up our work, each student writes a “State of the Creek Report” sharing their story and conclusions. Through a process of anonymous peer review and nomination, students select a report to be shared publicly here on the Hyla Woods website. This year I’m proud to share the class of 2027’s featured report…authored by Noah!
Thank you and congratulations, Noah, for your stellar work and for representing your class so well!
If—after reading Noah’s report—you’d like to dive deeper into our water quality database or read additional State of the Creek Reports from the other four finalists (Charlotte, Chloe, Sinead, and Tara) you can find these linked below
-Jesse Lowes (7th grade science teacher)
2021 Annual State of the Creek Report
Lousignont Creek, Site H
In October of 2021, the 7th grade science classes of Catlin Gabel School went to Hyla Woods, an experimental forest in Oregon’s Coast Range. Hyla Woods is an actively logged forest, but the owners (Peter and Pam Hayes) are trying to show that it is possible to log and still sustain a healthy ecosystem. Through the property runs a stream called the Lousignont Creek, which is a tributary of the Nehalem River. This is the body of water that we were testing. We were trying to answer the question: how can we tell if an ecosystem is healthy? We were investigating the health of the creek for Coho salmon, which would be returning from the ocean to spawn in late November into December. If the ecosystem wasn’t healthy, the salmon could have trouble spawning, which could lead to an even smaller Coho population.
The first trips were divided into two days, October 4th for some of the science classes, and October 5th for the rest of the classes. During the first round of trips, we spent half of the day writing poetry and the other half carrying out the water tests. When I was there (on October 4th), it was sunny, with an air temperature of 13 degrees Celsius. At my research site, we found that the trees were mostly deciduous and the beach was mostly rocky. The stream spanned one or two meters and was no more than half a meter deep. My group was extremely efficient, and we collected all of our data and placed our leaf pack in the first 45 minutes. A leaf pack is a bag of leaves designed to collect macroinvertebrates (small organisms that are visible with the eye, which don’t have a vertebrae). Macroinvertebrates like to live in clumps of leaves, so we basically made a home for them that we could remove from the water for later analysis. We also tested the air temperature, water temperature, pH, dissolved oxygen, and turbidity. These are all key factors in determining whether an ecosystem is healthy for salmon.
A submerged Leaf Pack, ready for macroinvertebrate move-in
Now, fast forward three weeks. For the second round of trips, we went in four groups who visited on the 25th, 26th, 27th, and 28th of October. My group went on the 25th, and we were carrying out our tests amid heavy showers, with an air temperature of 11 degrees Celsius. Now, the stream was two or three meters across, and too deep for the waders (in the middle). This time, we were doing the same water tests, but instead of creating a leaf pack, we were taking out our leaf pack. After removing our leaf pack, we detached all of the macroinvertebrates from the leaves and sediment. Then, we sorted them into different categories such as mayflies, caddisflies, and stoneflies. We were researching this because macroinvertebrates are animals that are relatively easy to identify and collect, and they provide insight into the health of the creek because some organisms are very sensitive to environmental impacts and will only be present when the creek is healthy. Macroinvertebrates are also a key food for salmon, so if they were dying off, that could take away a primary food source for Coho.
Students Working on dissolved oxygen tests
A student retrieving the Leaf Pack from Site E
When testing the water temperature, the optimal range for salmon is 5 to 20 degrees Celsius, though colder temperatures are preferable. Higher temperatures can lead to the spread of disease, to eggs hatching early, and to hurting salmon’s food supply. When we went to Hyla Woods, the average temperature of the water was 9.9 degrees Celsius. So, the water temperature was healthy for salmon.
When testing the pH, which is how acidic or basic the water is, the optimal range for salmon is 6.5 to 8.25. Too low/acidic a pH can disrupt the Coho’s smell and prevent eggs from hatching. On the other hand, a high/basic pH can lead to the shut-down of some bodily functions. When we went to Hyla Woods, the average pH of the water was 6.6. So, the pH in the water was healthy, but was on the more acidic end of the scale.
When testing the dissolved oxygen, which is the amount of gaseous oxygen molecules in every million molecules of water sample, the optimal range is 8 to 12 ppm (parts per million), but that’s just the minimum; salmon could live with more. Almost all animals need oxygen, and so do salmon; they couldn’t live without it. When we went to Hyla Woods, the average dissolved oxygen of the water was 9.2 ppm. So, the dissolved oxygen in the water was healthy for spawning salmon.
When testing the turbidity, which is the cloudiness of the water, the optimal range is as low (clear) as possible, and that would be around 6 NTU (Nephelometric Turbidity Unit) based on our procedure and conversions. If the turbidity is too high, aquatic plants can’t get enough sunlight; eggs and macroinvertebrates can get buried; temperature can increase, which causes the dissolved oxygen to drop; fish can choke and not be able to smell food; and algae populations can increase from the increased temperature, which can cause further blockage of sunlight. When we went to Hyla Woods, the median of the turbidity was 6 NTU. So, the turbidity at the creek was as good as it could be with our equipment.
When testing for the EPT score, which is the percentage of macroinvertebrates in our leaf pack that are mayflies, stoneflies, and caddisflies, the optimal range is anything above 50%. These three species of macroinvertebrates are really sensitive to changes in the environment, so if they were dying off, it could be potentially detrimental to the environment. When we went to Hyla Woods, the average EPT score was 61.33%. This high percentage of mayflies, stoneflies, and caddisflies (greater than 50%) indicates “excellent” water quality.
When testing for the Biotic Index, which is the average toxin level that the macroinvertebrates in the ecosystem can tolerate, a value below 3.75 would signify “excellent” water quality and a value between 3.75 and 5.00 means “good” water quality. If the biotic index is higher than this, that can suggest to us that sensitive macroinvertebrates can’t live there, so something bad is happening to the environment. When we went to Hyla Woods, the average biotic index was 4.22 suggesting the water quality was “good” (though not “excellent”) by this measure.
Students sorting out macroinvertebrates from the sediment
When I was analyzing the biotic index and EPT scores, I got really interested, and I decided to investigate more about how different ways of analyzing data matters when calculating EPT score and Biotic Index. If you would like to learn more, click HERE.
Based on all that data, we can conclude that the Lousignont Creek is healthy because we had excellent results on most of the tests. When I went to Hyla Woods, I really enjoyed hearing the rush of the creek, seeing the birds, and just being in nature. Peter Hayes read us a quote, from the poet Wendell Berry, that I really liked, “We have lived by the assumption that what was good for us would be good for the world. We have been wrong. We must change our lives, so that it will be possible to live by the contrary assumption that what is good for the world will be good for us.” I think that this quote represents exactly what the Hayes family are doing at Hyla Woods, they are changing the norm of how to log, and making it environmentally friendly.