River Herring & Eel Survey

About the Long Island Volunteer

River Herring & Eel Survey

The annual Long Island Volunteer River Herring & Eel Survey is one of Long Island’s longest running community science projects. Started in 2006, the survey engages community volunteer scientists to monitor runs of migratory river herring and American eels in rivers and streams across Long Island. The survey, organized by Seatuck and our partners at the Long Island Sound Study, Peconic Estuary Program and South Shore Estuary Reserve – aims to find the waterways where “remnant” runs of river herring still exist and then to monitor the size and timing of those runs. This information is vital to improve access and restore local populations of these ecologically important fish. Learn more about Diadromous Fish across Long Island here.

Participants in the survey are asked to commit to surveying a local waterway from mid-March through mid-May. The survey protocol involves visiting a neighborhood river or stream and spending 15 minutes looking for river herring or signs of their presence. The visits can occur daily, weekly or as often as possible. All data is good data – the more trained eyes we have on the water, the better! Observations and information from the survey visit are then submitted through an easy-to-use on-line application on your computer or mobile device and automatically becomes part of our study. The online app helps you to geo-locate your survey location and even submit photos.

River Herring & Eel Survey Resources

Events

Come join us as we celebrate World Fish Migration Day this spring!  Our first event will be at the WaterFront Center in Oyster Bay on Saturday, April 4th, 2026 at 10am.   A second event will be planned for later in April or early May.  Keep an eye out for updates!

Accessing the Survey 1-2-3 Mobile Field App

  1. First, you must download the free Survey 123 mobile app on your mobile device
  2.  Scan the QR code on the left using your phone’s camera. If you are currently on your mobile device, click here to download the River Herring & American Eel survey and proceed with steps 4 & 5
  3.  After scanning the QR code, click the top banner notification to open ArcGIS
  4.  Choose “Open in the Survey 123 field app”, and “Open this page in Survey 123”
  5.  Choose “Continue without signing in”

River Herring & American Eel Survey Map

Please Note: Clickable data points (shown in red) do not reflect confirmed sightings of wildlife. Each red dot indicates a survey submission.

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