LFWA Stream Team members were back in the Little Falls Branch for their winter monitoring February 6. Again, the weather was beautiful, the creek looked good, but it still is rated poor for its biological health. Only pollution tolerate organisms live in our creek and only 6 different species. And like winter 2021, the team did not find the required 100 organisms needed for a complete assessment.
They found 39 organism as follows:
Aquatic worm -2
Aquatic sow bug - 7
Midges - 11
Black flies - 5
Crane fly - 2
Common net spinner cadisfly - 12
The organisms are each assigned a number and to compute the Benthic Index of Biotic Integrity (B-IBI) score. The score for this monitoring was 1.3, at the low end of POOR. The creek has experience very high levels of salt in the past 6 weeks. This might be contributing to the low numbers as salt is toxic to these organisms. Learn about our salt testing program HERE.
Welcome new team members
LFWA is happy to welcome three new members to our monitoring team - Julie Miller, Phillip Mariscal, and Pauline Smith. They join team leader Frank Sanford, who along with 19 make up the LFWA Stream Team.
how do we monitor?
Our team does a quarterly benthic macroinvertebrate census of the creek. We use a D net to sample 20 spots along about 75 yards of the Little Falls creek below Massachusetts Avenue in Bethesda. The nets are emptied into tubs, and team members sort through the debris to find the organisms. We follow the protocol used by the Audubon Naturalist Society, our partners in this endeavor and report our data to them.
Benthic macroinvertebrates are the little bugs that live on the bottom of the creek, on the rocks and in the leaf packs. They are the link between the lowest level resources to higher trophic levels, including fishes. We monitor them as they are diverse, generally sedentary, responsive to environmental alterations, and are good indicators of ecosystem productivity and health.
More information about our monitoring program is HERE.
