The colored bars on this graph show the number of fish counted by volunteers each year at the different monitored locations. The brown line on the graph shows how many minutes volunteers spent looking for and counting fish each spring. This figure clearly shows the decline in herring counts that we have seen in the past few years. (Click on graph to enlarge.)

This spring, over 100 of our devoted volunteers spent more than 230 hours watching and waiting for river herring to make their way upstream to their annual spawning locations. The yearly spring migration is an important journey for river herring that is made difficult by obstacles such as dams, drought, pollution, and predation. Volunteer efforts to track this journey give us an idea of how many fish travel successfully to our monitored locations each year. We monitor streams all throughout the South Shore including Herring Brook, South River, First Herring Brook, Third Herring Brook, and Bound Brook. 

Stewardship efforts have led to the restoration of many streams in the area, which have increased the number of migrating herring in the past 10 years. One such stream, Herring Brook, had no fish before it was stocked in the late 2000s. The restoration efforts were very successful and led to Herring Brook having a substantial annual population of migrating fish. 

In the past couple of years, we have seen a decline in the number of migrating herring in many streams across the South Shore. There are a few hypotheses as to the cause of the decline, including lower freshwater flows as a result of droughts, ocean trawling, and changing conditions as a result of climate change. 

The work of our volunteers has been key to the detection of these population changes, and the data they collect supports population estimates which can give scientists and ecosystem managers alike a better clue into protecting these fish.