For 25 years, ANS has been teaching the natural history of aquatic ecology and training volunteer stream monitors who track the health of our region’s streams. Learn from the experts: study stream science in our introductory classes, and you just might be inspired to become a stream monitor yourself! Our advanced classes are perfect for those interested in deepening their knowledge about biological stream monitoring and are taught by our Maryland Biological Stream Survey-certified instructor Cathy Wiss. Our classes are great for fly fishermen, citizen science program or team leaders, aquatic resource biologists, and anyone interested in monitoring and understanding stream health.

Registration & Fee Information
Registration required. The classes are open to anyone 10 years and older. Prices for all classes are $15 Members/$25 non-members. Learn more and register at Contact with questions.

Know Your Invasive Plants
Woodend Sanctuary (Teale), Chevy Chase, MD
Saturday, September 15 (9:30 am-noon)

Invasive plants that kill or bring down mature trees can seriously alter stream health and ecosystem function. Volunteer Master Naturalist Diyan Rahaman will help you identify non-native invasive plants at Woodend and in nearby Rock Creek Park. An ANS/Rock Creek Conservancy Partnership.

Introduction to Stream Science Series*   
Classroom Session

Healthy Stream Biology
Section D: Thursday, September 20 (7-9:30 pm)

Woodend Sanctuary, Chevy Chase, MD
In the classroom, we will explore how “benthic macroinvertebrates” — organisms that live in the bottom of our streams – help us assess a stream’s health. We will learn how to identify these organisms to the taxonomic level of order through a PowerPoint presentation and by examining preserved specimens in a hands-on session with microscopes. 

Field Workshop

Section C: Saturday, September 22 (9:30 am – 12 pm)
Ten Mile Creek, Boyds, MD

In the field workshop, we will visit a healthy stream to practice monitoring techniques and to collect and identify the benthic macroinvertebrates we find.

How to Read Your Stream
Thursday, September 27 (7-9:30 pm)
Woodend Sanctuary, Chevy Chase, MD
Learn about the influence of land uses on streams, stream character and dynamics, bank erosion, bar formation, substrate composition, different velocity-depth regimes, and the importance of riffles and riparian vegetation. We will practice assessing stream habitat by using photgraphs of streams and the forms that monitors fill out in the field. This class is recommended for anyone who plans to participate in the ANS water quality monitoring program and is a good refresher on habitat assessment for experienced monitors.

Learn more and register at