Catch the Hatch

Mayflies are important indicators of watershed health and are threatened by disturbances and climate change. With more than 100 volunteers, we have tracked emergence patterns in relationship to creek temperature and flows since 2019. After three successful years of monitoring, we will be taking a break and will run another season as needed to document changes in emergence over time or in response to future disturbances (e.g. flood, drought, or fire). Please stay tuned for another monitoring season in the coming years! Learn more about project details here .

Dave Rees, Timberline Aquatics

Catch the Hatch

Mayflies are important indicators of watershed health and are threatened by pollution and climate change. Join our team this summer from June 15- July 15. Record data on mayfly emergence and creek temperature at three creek locations in the St. Vrain sub-basin. Becoming a data catcher means you will train with scientists and make observations on your own schedule! Learn more about project details here .

We have successfully tracked mayfly emergence for three years! Check out our data summary below to learn more about when we saw emergence and at what temperatures and flows.

Catch the Hatch Observation Locations

Click on the map to see summer observation locations.

Hatch charts from previous seasons

Catch the Hatch aims to track Pale Morning Dun mayfly emergence during their peak emergence window (June 15 through July 15) in relationship to environmental variables, such as flow and creek temperature, from year to year.

Take a look at the hatch charts below. Do you see any differences in the timing of emergence observations or the associated creek temperature or flow from year to year?

Left Hand Watershed Center’s Community Science Program aims to engage Front Range communities in place-based learning and scientific data collection about watershed health. Please learn more about our Community Science Plan or help support future projects!