As the school semester winds down, lessons for the Aquatic Ecology class I've been teaching have been easier to prepare. For the past three weeks, we've been taking field trips! Field trips are so important to learning; while those experiences may not have included the most informational content, the knowledge gained was always so much more memorable. They also open opportunities for creativity and questioning that seem closed off in most students (and teachers) within the confines of a traditional classroom.
To start, we explored a park along the Meramec River in search of wetlands to delineate. This was part two for wetland ecology, as I had gone through a brief explanation of the concept of wetland delineation and how to identify soil type a few weeks ago. During the field trip, the challenge was actually more about finding areas in the park that were NOT wetlands. The river had just flooded the previous week.
Before the semester started, it hadn't crossed my mind to include a trip to a fish farm for an ecology class. Fortunately, I have Megan to toss ideas my way. She worked at the St. Louis Fish Farm while she was an undergraduate and, when I was trying to figure out what we might want to do during a lake/pond field trip, she mentioned that Mike, the owner of the fish farm, would probably be glad to host us. What a great idea!! Not only did we have a chance to explore a different ecosystem, but there were opportunities to consider the support systems are put in place at a fish farm, what ecological function these systems serve, and why the farm pond does not provide these services without human intervention.
During the visit, several students had an opportunity to try to catch a fish with the nets - each of them took several tries to catch a fish and some never did get one. I wanted to try, but made sure that all of the interested students had a shot first. I was a bit concerned that I would somehow embarrass myself - not only did I manage to catch a fish, but I got it on my first try! I was pleased to represent the Knouft Lab so successfully!
Initially, our field trip to the National Great Rivers Research and Education Center was scheduled for early April. Unfortunately, the flooding on the Mississippi River forced us to postpone the trip. On the other hand, this trip was completely worth the wait! The class split into two groups: one group toured the NGRREC research facility while the other group went out on the Mississippi in the research boat to explore monitoring methods for big rivers. It was very interesting to compare how methods change when you move from a wadeable stream to such a vast aquatic habitat.
In early March, I was scrolling through my Twitter feed - a social media platform I use almost exclusively for science communication (and occasional Blues hockey) - when I saw a Tweet from Matt Schuler about Tyson Research Station. They had reduced their use of road salt this winter by using brine.
I was so glad to read about a local organization taking advantage of brine, that I actually clicked on the article and read all about their brining system. That was when I got REALLY excited. You see, the article mentions "a Brining Workshop organized by [Washington University] and the St. Louis Higher Education Sustainability Consortium." I was one of the two speakers at that workshop! This is the first time that I can say for certain that my research and my outreach efforts have resulted in a change in how road salt is used. They report using only a fifth of the amount of salt that they would have used without their in-house brining system. And, not including the things they already had on-hand, it only cost them $100 to put together the system.
I love success stories like this! If you know of any other groups that have started using brine and are having success at cutting their salt use, please comment so we can spread the word!
Since my research is on winter use of road salt, much of my field work has been completed in the winter. I've spent days climbing down storm drains to learn about municipal salt use. This year, the Wednesday before Thanksgiving, I spent the day in the field with Cathleen Yung (an undergraduate student who has been helping me in the lab) and my helpful husband Hogan. We visited Sugar Creek in order to hunt for a large number of a single species of flathead mayfly for a toxicity study that I would be conducting over the following two weeks.
Normally, I wouldn't consider field work before Thanksgiving to be winter field work, but when we arrived at the site, the water temperature was only 3 degrees C and there were small patches of ice along some of the stream banks. We proceeded to spend about 7 hours in the chill water (with waders on), picking up many small rocks (and several not-so-small rocks) with our bare hands in order to look for our mayfly friends. While slow and tedious, this hand collecting method is the most effective for gathering wild specimens without causing injuries to the delicate critters - as long as you can still feel your fingers.
By the end of the day, we had collected over 450 mayflies. As someone who is working to preserve aquatic life, there is a part of me that regrets taking so many animals from the stream. Fortunately, I know that this stream is supporting a very large and healthy population of this species. Within the 120-meter segment of stream where we sampled, we left large patches of habitat undisturbed and did not take the smaller individuals. In addition, there were many other patches of prime habitat both upstream and downstream of the area where we collected. I share these bits of information because I want to make it clear that, as a responsible scientist, I consider the environmental costs and potential long-term effects of any collection efforts that I undertake.
Before I close out this post, I need to express my gratitude to my two amazing helpers. Hogan and Cathleen not only helped get the job done, they were cheerful and enthusiastic about it! I could not have asked for better help in less-than-comfortable conditions!
Last week, I was visiting my field sites to collect invertebrates and download data. While I was enjoying the fall weather, I got to thinking about losing streams. I don't mean that I was concerned about losing a stream; I'm talking about streams that have flowing water for a stretch and then, a short distance downstream, there is no water! In a losing stream, the water is "lost" into the groundwater system.
I have seen evidence that at least two of the streams that I am studying are losing streams: Deer Creek and Hamilton Creek. I've even taken video of this phenomenon at one of the sites:
I am often awestruck by the complexity of nature. The phenomenon of losing streams - which often resurface from a spring a short distance away - is one of these complexities. It isn't that the concept is complex, but rather the implications of the existence of these streams. When the water is lost, that segment of stream changes from an aquatic ecosystem to a terrestrial ecosystem. This removes habitat from one set of species (which may or may not escape the loss of water) and temporarily creates a completely new type of habitat. Also, a path of dry land is created that permits the movement of small terrestrial animals (eg., spiders, ants, and flightless beetles) across what is otherwise an impassable boundary. And then there are the questions of how this may impact the chemical composition of groundwater, especially in streams that carry runoff that is polluted by human activities.
Missouri is home to many losing streams, especially in the Ozarks where much of the bedrock is limestone. Limestone is relatively easily weathered or dissolved, resulting in an abundance of sinkholes and caves. The predominance of this type of rock is one of the reasons that Missouri has claimed the moniker "The Cave State". The Missouri Department of Natural Resources has many interesting resources if you'd like to read more about caves, springs, and losing streams in the state.