The Herring Are Coming!

Bio100 Visits the Shawsheen River

This year’s Bio100 class had the unique opportunity to visit the Shawsheen River last week and learn a bit about habitat change. Each period piled into a bus and drove down to near Whole Foods in Andover to a bridge overlooking the Shawsheen River.

There, they met Jon Honea, a professor at Emerson College in Boston whose research involves making computer models to see how habitat change effects different communities. In this particular spot, two dams that were built approximately 200 years ago were taken down to allow the migratory fish to return to the area. He is now monitoring the return of the fish that used to be native to this area, namely the River Herring. These fish are silver in color and about a foot long. Mr. Honea and his team are watching the river for about 10 minutes at a time to see how many of these fish are spotted. This data will help to estimate the fish’s spawning population time.

Mr. Honea talked to them a bit about why it is so important for us to repopulate the river with this Herring. They play an important role in the ecosystem as food for many animals. They spawn in fresh water rivers and then move to the ocean to grow up. Mr. Mundra also talked a bit about the two dams that were removed from the area. These dams were preventing the fish from coming back to spawn in the river. These dams were built approximately 200 years ago as a source of energy for the Powder Mills in the area. Mr. Honea also said that the downstream dam was purely ornamental – the owner of the Mills wanted a gurgling sound for his administrative staff to feel comfortable working in the building.

The class then helped Mr. Honea to count the fish in the river. They took some basic data down, the weather and temperature of the air and water, and began to look for the fish. We are looking for the stray fish who are now able to make it upstream, to see how many make it up now that the dams are gone. Unfortunately, in the 10 minutes that we were there, no one saw a fish, but the hope is that within the next three or four years the population will be thriving!