On Tuesday, June 21st, the Alliance for the Chesapeake Bay conducted a macro-invertebrate study at Barshinger Creek behind Red Lion Middle School in York County, PA. Here, a group of 10 elementary and middle school students waded through the creek and used nets to collect aquatic wildlife like fish, tadpoles, salamanders, and all sorts of insects. Some students were upstream, flipping over rocks and stirring up the water, while others were downstream collecting organisms that were caught in the current. They ended up finding at least 10 different species including tadpoles, a black-nosed dace fish, salamanders, water striders, orb snails, dragonflies, isopods, alderflies, damselflies, crane flies, and threadworms! The presence of these macro-invertebrates indicated that the creek is in good health and (relatively) free of pollutants! 

Students listening to Alliance Staff members talk about the benefits of Macro-invertebrates

A few of the macro-invertebrates collected from students

This activity not only taught the students how to tell if a creek is healthy and good for fishing, but also the importance of riparian buffers. A riparian buffer is a vegetated zone that surrounds a body of water. The trees and plants in this strip of land do a number of things to keep the water healthy. The roots of the plants hold the soil together to prevent erosion as well as to filter out pollutants before they reach the creek. Trees provide shade for the creek, keeping the water cool and oxygen-rich, which allows larger invertebrates like fish to survive. In addition, leaves from plants are a key component of aquatic food chains, providing nutrients for the creek’s smaller invertebrates. The students also learned about how pollution ends up in the Chesapeake Bay, including the difference between point and nonpoint pollution. Point pollution is when you can clearly identify the source of the pollutants like a discharge pipe from a factory or sewage plant, while nonpoint pollution is pollution that’s carried into the bay via rainwater. Most of the pollution in our watershed is from nonpoint pollution like agricultural and urban runoff, which is why riparian buffers are so important. Without these barriers between the land and water, runoff flows directly into it, which can disrupt the chemical composition of the ecosystem by introducing too many nutrients. Although one would think that an abundance of nutrients is a good thing, too much can cause algae blooms that remove oxygen from the water, which can kill organisms living in the creek. Therefore, if we wish to preserve the Chesapeake Bay and the organisms that call it home, we must start with protecting the forests that surround our creeks and streams. 

“In a world and education system that puts so much emphasis, time, and learning into the devices made widely available to us in the past 2 decades we still long for interaction with the natural world. My students through collaboration with The Alliance for the Chesapeake Bay were able to get messy and interact with an entirely new world right in their backyard. This wouldn’t have happened without Rob and Rebecca. The Red Lion Area School District is very blessed to have such a gem so close to the junior and senior high that we can use,” Dan Dellinger 8th Grade Sci. Teacher.

This blog was written by Sean O’Connor, our LGAC and Communications Summer Intern. He is a current Environmental Studies Major at Franklin & Marshall College. Learn more about Sean here!