By: eric reutebuch
The AU Urban Ecology class (FORY 4970/7970), taught by Dr. Chris Anderson, met with Eric Reutebuch and Sergio Ruiz-Cordova in September to learn about Alabama Water Watch(AWW) and to examine two local streams using the AWW Stream Biomonitoring protocol. The class sampled Saugahatchee Creek (at Lee County Road 65 Bridge) first, then sampled Parkerson Mill Creek (at Sandhill Road).
Photos of stream sampling
The students utilized small seines and kicknets to collect macroinvertebrates (aquatic insects, snails, crayfish and clams) to assess the ‘health’ of the two streams. The AWW stream bioassessment protocol is based on the collection of a stream’s macroinvertebrate community and examining the species diversity and abundance of the community. The aquatic critters are identified and placed into three groups, Group I are the most sensitive to pollution and physical disturbance, Group II are moderately sensitive, and Group III are tolerant to pollution.
At the Saugahatchee, the students found a fairly diverse group of stream critters, including snails, mayfly nymphs, stonefly nymphs, caddis fly larvae, riffle beetles, damselfly nymphs, hellgrammites, clams, midges and a leech, for a total of 11 different aquatic species. From their collections, they then calculated a stream quality assessment score to rate Saugahatchee Creek, which yielded a value of 25, equivalent to a rating of ‘Excellent.’ In other words, given that the headwaters of the Saugahatchee are urbanized and receive some pollutants from urban point and nonpoint sources (Opelika-Auburn municipal treatment effluents, chemicals and pet waste from lawns, motor oil from driveways and parking lots, etc.), the stream at Lee CR 65 Bridge supports a diverse community of aquatic organisms, and is in relatively good shape. An important caveat to these findings is that the AWW Biomonitoring protocol yields a ‘conservative’ estimate of stream health, meaning that it tends to overestimate stream health (conversely, it tends to underestimate negative impacts to stream health).
Stream assessment results – Saugahatchee #1
Stream assessment results – Saugahatchee #2
Stream assessment results – Parkerson Mill
At the second stream, Parkerson Mill Creek at Sandhill Road (just south of Auburn) the students again found a fairly diverse group of stream critters, including snails, mayfly nymphs, caddis fly larvae, water pennies, dragonfly and damselfly nymphs, hellgrammites, midges, aquatic worms and a leech, a total of 12 different aquatic species. From their collections, they calculated a stream quality assessment score of 24 for Parkerson Mill Creek, which also yielded a rating of ‘Excellent.’ Parkerson Mill was recently placed on ADEMs 303(d) list of impaired streams for pathogen contamination (primarily E. coli bacteria). It appears from these data that the aquatic macroinvertebrate community is relatively unimpacted and in fairly good shape.
The students thoroughly enjoyed their stream bioassessment experience, and gathered valuable real-world skills and informative data in the process!