Finding a bug in your water may be a good sign! In this Spot on Science, Margaret heads to a stream to learn about how citizen scientists are able to count water bugs as a way of monitoring water quality.
Class Discussion Questions:
1) What can bugs tell us about water quality?
2) What important role do you think crayfish play in a river ecosystem? Support your answer with information from the video.
3) What can you learn from the presence of hellgrammites in your river?
Read the Script:
[Margaret] Ah there's nothing better than finding a bug in your water, right? Okay, so maybe not your glass of water. But in the streams and rivers around us, bugs can be a sign that the water is clean enough to call home. To find out a little more, I met up with Matthew Smith.
He works for the Ohio Department of Natural Resources and helps teach community volunteers how to look for signs that the water is not polluted by counting the bugs they find in their neighborhood streams. Take a look.
[Matthew] Most people think of bugs and they go, "Ew, yuck," you know, "bugs!" But, actually we want to see a lot of bugs especially a huge diversity of different types of bugs. Right now, we're in the village of Mantua and we're at Buchert Memorial Park. We're setting up to have a workshop for people to come out and learn about stream quality and about the upper Cuyahoga State Scenic River. We sample the macroinvertebrates that live in the stream. Those are the small little bugs that spend most of their lifecycle in the stream.
[Margaret] Matthew Smith and his co-worker from the Ohio Department of Natural Resources taught about 15 folks how to tell if the upper Cuyahoga River is looking clean. By catching bugs, identifying them.
- Some fly, nymph.
[Woman] That's a nymph, okay.
[Margaret] And counting them. It's almost like a game. Different bugs are assigned different scores based on how sensitive they are to pollution.
[Matthew] And we look for some of these macroinvertebrates because some of them are very sensitive to pollution. Some bugs can tolerate a lot of pollution and other bugs can't handle hardly any at all. So, when we sample the water quality by looking at the bugs if we find certain organisms we know that the water quality is fairly good.
[Margaret] So, what are some of these important bugs?
[Matthew] What I have right here, this is actually a Damselfly Nymph and it's basically just like a little kid Damselfly. And it'll live in this stage in the water and it'll feed on little bugs and little tiny fish until it becomes an adult. And it has three tails and these three tails that it has right here are actually it's gills and that's how it breathes. It gets dissolved oxygen out of the water.
This is a Crawdad, a Crayfish. These are totally aquatic. They live in the water at all times. There are terrestrial Crayfish or Crayfish that live on land but we're only looking at the ones that live in the water. And these guys eat just about everything that they can get ahold of. They'll eat some of the dead things that are in the water. They'll catch live fish and eat them. They'll also eat other bugs. So Crayfish are not ... They're kind of like mid level tolerance to pollution. They're not extremely sensitive to pollution. They don't have to have the cleanest of clean waters.
This is a Dobsonfly Larvae. The nickname for it is called Hellgrammite. And Hellgrammites live in this stage in the stream for three years. And Hellgrammites are very sensitive to pollution. They need very clean water and this one is probably about a year to two year old Hellgrammite. They probably get almost about three inches long. And if you get a three year old Hellgrammite that's been living in the stream, you know that that stream has had good water quality for three years, because they're very sensitive to pollution.
[Margaret] Keeping the Cuyahoga River clean isn't just helpful for keeping the little water bugs healthy. The water here is actually used by the city of Akron. Residents there use it for everything from drinking to washing clothes. That's why volunteers turn in their water bug scorecards to the department, who will investigate if problems are found. Matthew says it's a team sport.
[Matthew] We have people who live around here that sample the water quality. They become more interested in trying to protect that stream and trying to keep it healthy and maintain the healthiness of the stream. That's really important, especially if people can bring their kids out and teach them about the bugs that live in the stream and about how healthy the water is. And when they grow up hopefully one day they can help keep this stream, this river beautiful and healthy.