Welcome to the Mystic River Herring Video Counter!

Help us track changes in river herring populations over time by counting the number of fish passing through the fish ladder at Upper Mystic Lake dam located between Medford and Winchester, MA.

The videos are between 10 and 60 seconds long. Some videos show blue outlines when motion is detected, but some do not.  Here are our results so far - but we need your help to continue this important conservation mission.

If you have not been to this site before, please take a moment to view the instructions and learn what to count and what not to count, which is important for us to collect accurate data. If you've already seen the instructions, then let's start counting!

About the Fish Ladder and Video System

In 2017, the Mystic River Watershed Association, together with the Massachusetts Division of Marine Fisheries and Massachusetts Department of Conservation and Recreation, installed an underwater video camera at the Upper Mystic Lake dam between Winchester and Medford, MA (see map below). The camera is set up to record video clips whenever it detects one or more fish passing through its field of view. These video clips are uploaded to this website in real time so that anyone from anywhere can help count how many fish are migrating up the Mystic River. With this data, we can more accurately track how the migration changes from year to year, and thus better understand this valuable species. Learn more about the project and explore data.