Project Overview:

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Every year, mayflies emerge from the Mississippi River, and the result can be extraordinary! These insects can swarm by the millions during a large emergence — enough to be picked up by weather radar.

Mayflies are an important food source for fish, especially during the summer emergence but also throughout the year when they are in their larval form. Mayflies are also a public safety hazard when they swarm near lights on roads and bridges, as they can pile up and cause roads to be slick and dangerous for cars. 

The US Fish & Wildlife Service is interested in tracking the timing of seasonal events like these. In the long term, this citizen science-based research will help educate the public that the presence of these insects is an indicator of generally good local water quality conditions during the past year. Information on the predicted timing of emergence can inform managers when to take measures to ensure the public's safety, such as turning off lights on bridges and encouraging drivers to stay off roads inundated with mayflies.

See what we learned from this campaign in 2023.


You will receive messages full of findings, observation tips, and campaign-specific opportunities. Don't miss out!

How to Participate

1. Join Nature's Notebook. If you haven't already, create a Nature's Notebook account. If you need more details on getting started, take the Observer Certification Course at 

2. Set up your Observation Deck. Set up a Personal Site and add one or both of the mayfly species to your site. Follow these instructions on how to create a site and add animals.

3. Observe mayflies. Report what you see (yes/no/not sure?) for mayflies following the instructions for mayflies or giant mayflies. You should survey the area within 5-10 ft of where you are standing. You may need to walk around the area, inspecting the vegetation along the shoreline for several minutes.

Remember, mayfly abundance may change hourly - you can report multiple observations in one day by reporting the time at which you made the observation.


You can earn this badge by reporting a "no" followed by a "yes" observation within the same year for mayflies.

See it on your Observation Deck.

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