They’re creepy. They’re crawly. They’re also an excellent indicator of water quality– they’re the aquatic insects and animals that live in Pennsylvania’s rivers, lakes, and streams.

The Department of Environmental Protection is for the first time visualizing benthic macroinvertebrate sampling results from across the state. The data is now publicly available in a GIS viewer with downloadable data sets for the first time as well.

Benthic macroinvertebrates are the insects and animals that spend most, if not all, of their lives underwater. They can be mayflies or midges, crayfish or clams, or one of many other underwater species, and are one of the most important parts of the food chain that fish, birds, and other animals depend on.

“Because they spend almost their entire lives in the water, benthic macroinvertebrates are especially attuned to water quality,” said Dustin Shull, Water Program Specialist for DEP. “They are an excellent way to gauge how healthy a particular section of stream or river is, and help DEP meet our obligations for monitoring water quality. This kind of biological assessment helps DEP see and assess long-term, cumulative effects of stressing factors on an ecosystem.”

Not all streams and rivers are created equal, and DEP has developed unique macroinvertebrate collection methods for freestone streams, limestone streams, and low-gradient streams.

DEP uses these differing methods to get a complete picture of how many, what type, and how healthy the invertebrates are in any given habitat.

“DEP and partners have collected thousands of samples, and collect hundreds more every year to continue to deepen our knowledge base on the health of Pennsylvania’s waters,” said Shull.

See examples of the different streams types, the methods used to sample them, and results of the sampling by visiting Looking Below the Surface, DEP’s interactive story map on benthic macroinvertebrates.

“This type of research is vital to decision-making that goes on at DEP,” said DEP Secretary Patrick McDonnell. “We use the data collected and analyzed by program staff when we’re looking at how to clean up watersheds and improve water quality in backyards and communities across Pennsylvania. And we want to make sure that Pennsylvania residents can see the data we’re collecting, so they can know more about what is happening in their own area.”

To learn more about benthic macroinvertebrates, sampling, and water quality, please visit DEP’s Looking Below the Surface website.

To retrieve sampling data, please visit DEP’s Macro Viewer webpage.

For more information on environmental programs in Pennsylvania, visit DEP’s website, Click Here to sign up for DEP’s monthly newsletter, visit DEP’s Blog,  Like DEP on Facebook, Follow DEP on Twitter and visit DEP’s YouTube Channel.

[Posted: Dec. 11, 2017]

12/18/2017