Over the last 30 years, invasive species like zebra and quagga mussels and the round goby have rapidly and completely changed the water quality and ecology of Lake Michigan.
Throughout this period, the staff, instructors and students of the Inland Seas Education Association (ISEA) have carried on a consistent, scientific sampling program in the Grand Traverse Bay and Lake Michigan. This 30-year, multi-point data set clearly describes and documents massive changes in the ecology and water quality of this area of Lake Michigan. And with massive driving forces like climate change and invasive species, the Lake is continuing to change – rapidly.
Beginning with founding director, the late Tom Kelly, staff members of ISEA have been taking instructors and students of all ages out onto Grand Traverse Bay dozens of times each year for direct, hands-on learning experiences about freshwater ecology.
In this video, ISEA’s Lead Scientist, Jeanie Williams describes some of the sampling methods used and the data collected by students and instructors. A key data set gathered by the instructors and students over the decades, Jeanie says, is water clarity as measured with a secchi disk. She says the data tell a story of dramatically increasing clarity, as the invading mussels have cleared the water of plankton, a critical part of the food chain.
Volunteer Lead Instructor, Sue Chrostek describes the rapid decline in the diversity of small fish found in Grand Traverse Bay after the arrival of the round goby in 2005 and 2006. By 2015, the round goby appeared to have replaced or overrun well over 90% of all other small prey fish caught by ISEA in the bay.
But, as Sue tells us, that trend might be changing. Fish collected in the last two years are showing greater diversity, including the occurrence of a native fish known as the Iowa darter.
Executive Director Fred Sitkins says the data collected consistently over the decades shows the trends in ecosystem health and helps to paint a clear picture of the impacts of invasive species that everyone can see. In addition to building deep appreciation for the Great Lakes, Fred says, these sailing experiences help inspire science students of all ages.
Watch this video to see and hear the whole story!