Maine Stream Explorers 2021 “A Treasure Hunt to Find Healthy Streams in Maine”
Would you like to get your feet wet, sort through dozens of tiny creatures that look like Dr. Seuss invented them, and then take great satisfaction in submitting photos and data that answer important water quality questions about Maine streams?
Yes? You would? You are a special person!
If this sounds like your idea of fun, consider signing up to be a Maine Stream Explorer! This summer, you and a partner will stand in a Maine stream, scuffing stones, submerged plants and exposed tree roots with your hands and catching the detritus with a net downstream.
On the streambank you’ll empty your net into trays and start looking for aquatic insects and other creatures large enough to see, aka macroinvertebrates. You will compare what you find with a checklist full of images to determine which ones are sensitive, moderately sensitive or tolerant of water pollution or impaired water conditions. You’ll take photos, submit data, clean up and return your critters to the stream. Then, pat yourself on the back for a job well done!
Photo by Hannah Young
Why would anyone do this?
To answer this question I called up Hannah Young, who coordinates the Maine Stream Explorers program for Maine Audubon.
Hannah reminded me that Maine has over 5,000 rivers and streams. Most of them are healthy, but many are at risk due to changing climate and land use patterns. Maine’s Department of Environmental Protection (DEP) is charged with monitoring stream water quality changes over time, but only has the resources to sample 50-60 streams per year. So they are turning to community science volunteers. Their sampling results help the DEP prioritize its own in-depth water quality efforts.
Photo of a healthy stream by Cathie Murray
Insects are the key.
How can volunteers easily and reliably monitor stream water quality? It turns out aquatic insects are the key. You probably know that some of Maine’s most iconic streamside insects (think dragonflies, damselflies, black flies) spend their immature life stages in the water. It turns out these macroinvertebrates are like “canaries in the coal mine.” They are excellent indicators of water quality because different species can tolerate more or less exposure to pollution and other environmental stressors.
Hannah shared with me how scientists looked at the 1,400+ species of macroinvertebrates that DEP has found in Maine streams over the years, chose several dozen of the most useful species, genera or orders, and then divided them into three groups:
“Sensitive” macroinvertebrates require cold, clean water and unimpaired habitat.
“Moderately sensitive” species can tolerate a bit more pollution, sedimentation and degradation.
“Tolerant” macroinvertebrates are tough. They can usually live in clean streams but they can also handle warmer temperatures and more polluted water and disturbed habitat.
Here are some examples of how familiar macroinvertebrates sort out. All our common stoneflies are “sensitive”, some mayflies and caddisflies are “sensitive” while others are “moderately sensitive”. Midges, amphipods and isopods are “tolerant”. Clubtail dragonflies are “sensitive” while the Darners we’d be likely to see are “moderately sensitive.”
Streams that are healthy generally have more kinds of “sensitive” macroinvertebrates, along with some “moderately sensitive” and “tolerant” organisms. In a polluted stream “tolerant” macroinvertebrates will be the most abundant kind and there will be few or no sensitive organisms. As Hannah explained, the proportionate representation of these different groups gives DEP very good information about the status of water quality in the stream.
The two collections below show the dramatic difference in macroinvertebrates in a healthy stream versus a polluted one.
The first figure demonstrates macroinvertebrates from a stream with good water quality
The second figure demonstrates macroinvertebrates from a severely polluted stream
Blue = sensitive | Green = moderately sensitive | Purple = tolerant
Last Year’s Results
The Summer of 2020 was the first year Maine Stream Explorers were in the field. Hannah noted the focus was the Sebago Lake watershed, crucial for the City of Portland’s drinking water. Partners included Maine Audubon, Maine DEP, the Portland Water District and the Lakes Environmental Association.
Twenty four volunteers completed the Maine Stream Explorer training. Volunteers included families with young children, retired folks and even a visitor from out of state who got so excited about it he brought his own field microscope to view aquatic insects in greater detail. They surveyed 26 streams, many that had never been sampled by Maine DEP before. At one extreme, they found 5 streams with high quality, diverse macroinvertebrates. At the other, they found several streams with only 0 - 1 sensitive or moderately sensitive organisms.
Photo taken at College Swamp Brook by Kim McCubrey
This Year
Maine Stream Explorers is expanding this summer to include other streams in southern Maine that aren’t necessarily in the Sebago Lake watershed. If you would like to be involved, put on your sun hat, your anti-tick shirt and your water shoes! Get ready to do some detective work that combines curiosity about aquatic insects with a willingness to get your feet wet, literally!
According to Hannah, this is what’s involved:
Volunteers must register here and watch two training videos to learn how to identify the different types of aquatic insects you are likely to find, and how to conduct the survey.
[Note: The two training webinars will be live on May 5 and 6 at 7 pm, or you can go through the recorded versions later, available via YouTube. Do not use last year’s videos as the protocols have changed. MES members, even if you know a lot about aquatic insects, the protocols for collection and data entry will be critical.]
Volunteers will be provided a guidebook that includes an overview of the program, details on how to conduct a stream survey, tips for identifying a select list of stream insects, survey data forms, and contact information for participating partners. We will also have recordings of the webinars and a virtual tour of a stream survey available for viewing and reference. All materials will be available digitally and hard copies may be requested if absolutely necessary.
Survey equipment kits will be available for check-out, loan and curb-side pick-up at various partner organizations and locations.
Optional field training will be held this summer in Auburn, Bridgton and Falmouth. And the MES field trip on May 22 will include field training for Maine Stream Explorers.
We encourage interested volunteers to commit to surveying at least one, but preferably two to three streams by October 2021. Each survey will take around 1.5 to 2 hours to complete, plus travel time. [Note: you can survey longer if you are having fun!] We also encourage volunteers to survey in pairs for safety reasons. You can make a family adventure of it.
Article written by MES member Cathie Murray.
Please contact Hannah Young (hyoung@maineaudubon.org) for more details.
The Maine Stream Explorers project is funded by a grant from the Maine Outdoor Heritage Fund.
