FOSC/Nature Forward (formerly Audubon Naturalist Society)
Biological Water Quality Monitoring/Data

Nature Forward has a well established, highly regarded macroinvertebrate monitoring program in the region. Friends of Sligo Creek began monitoring one site on Sligo Creek using Nature Forward’s water monitoring protocol in 2006. The site is located on Sligo Creek just south of where Sligo Creek Parkway meets University Boulevard in Wheaton (select the purple triangle on the map at right).

The primary goal of the monitoring is to have data for Sligo Creek represented in Nature Forward’s data set, which is periodically turned over to Montgomery County to help them assess the water quality of County streams. Other goals include public education, and to see for ourselves whether Sligo Creek’s water quality is getting better or worse over time. The Sligo Creek site has been named Audubon Naturalist Society (now Nature Forward) Site 34.

Macroinvertebrate Monitoring Sites in Sligo Creek

Biological Monitoring Sites on Sligo Creek.
The site monitored by FOSC is located just south of University Boulevard, marked with a purple triangle

The Water Quality Committee also conducts periodic cross section surveys of the stream channel at this site to see how it changes over time.

Keep an eye out for future monitoring events on the FOSC listserv (see the link on the Home page) and join us! The next monitoring will take place in Spring 2023. You can join FOSC to get event updates and the newsletter delivered to your inbox.

NOTE: Due to the COVID pandemic, biological monitoring was suspended in Spring 2020 with intermittent testing in 2021.

FOSC/NF Biological Monitoring Results

for the Nature Forward Site 34 in Upper Sligo Creek

Date Total Aquatic Worms

(Oligochaeta) or Flatworms, Planarians


(Platyhelminthes)
Caddisflies (Trichoptera) Crayfish (Decapoda) Dragonflies and Damselflies (Odonata) Mayflies (Ephemeroptera) Scud (Amphipoda) Snail (Gastropoda) True Flies (Diptera) Clam (Bivalvia) Beetles (Coleoptera) Fishflies, etc. (Megaloptera) True Bugs (Hemiptera)
10/24/2022 47 2 planaria 17 netspinner, 22 fingernet 1 0 1 (small minnow mayfly) 2 0 0 1 (Asian) 1 riffle beetle (adult) 0 0
7/25/2022 100+ 4 aquatic worms, 12 planaria 75+ netspinner, 3 fingernet 1 3 darner dragonflies 0 2 0 6 midges, 3 crane flies 0 0 0 0
4/30/2022 100+ 22 aquatic worms 25 netspinner 1 0 65+ (small minnow mayflies) 0 0 10 midges, 4 crane flies 0 0 0 0
10/15/2021 44 1 planaria 35 netspinner, 3 fingernet 1 0 1 (small minnow mayflies) 0 0 3 crane flies 0 0 0 0
7/13/2021 67 1 planaria 60 netspinner 1 0 2 (small minnow mayflies) 0 0 3 midges 0 0 0 0
10/26/2019 102 3 planaria 38 netspinner, 55 fingernet 0 0 0 2 0 2 midges, 2 crane flies 0 0 0 0
7/23/2019 100 3 aquatic worms, 4 planaria 55 netspinner, 40 fingernet 2 0 0 0 1 (pouch snail) 5 crane flies 0 0 0 0
4/25/2019 100+ 2 aquatic worms 50+ netspinner 0 0 14 (small minnow mayflies) 0 0 21 midges, 4 crane flies 1 (Asian) 0 0 0
10/13/2018 116 0 64 netspinner 0 1 narrowed-winged damselfly 0 30 0 4 midges, 9 crane flies 7 (fingernail) 1 riffle beetle (larva) 0 0
7/31/2018 99 3 planaria 74 netspinner, 8 fingernet 0 0 0 3 0 3 midges, 6 crane flies, 1 black fly 0 0 0 1 short-legged strider
4/28/2018 40 2 aquatic worms 20 netspinner 0 4 narrowed-winged damselflies 0 3 0 10 midges, 1 black fly 0 0 0 0
10/28/2017 60 0 50 (40 netspinner, 10 fingernet) 0 0 0 0 4 (pond snails) 6 midges 0 0 0 0
4/27/2017 25 0 0 0 0 0 0 0 25 midges 0 0 0 0
10/29/2016 13 1 aquatic worm 2 0 0 0 0 0 10 (5 midges, 5 mosquitos) 0 0 0 0
7/18/2016 54+ 1 aquatic worm, 8 planaria 8 0 0 6 (small minnow mayflies) 0 0 31 (30+ midges, 1 crane fly) 0 0 0 0
4/30/2016 100+ 2 aquatic worms 0 0 0 0 2 0 96+ (95+ midges, 1 crane fly) 0 0 0 0
10/31/2015 13 0 4 0 4 broadwinged damselflies 0 0 0 5 (4 midges, 1 crane fly) 0 0 0 0
7/29/2015 11 1 aquatic worm 1 0 1 darner dragonfly 1 (small minnow mayfly) 2 1 (pond snail) 3 (2 midges, 1 crane fly) 0 0 1 (dobsonfly) 0
4/25/2015 100+ 0 20 0 0 0 0 2 (pond snails) 78+ midges 0 0 0 0
10/18/2014 10 0 7 1 0 0 1 0 1 midge 0 0 0 0
7/22/2014 100+ 0 71+ 0 5 damselflies 3 (small minnow mayflies) 4 8 (pond snails) 9 (8 midges, 1 crane fly) 0 0 0 0
4/25/2014 14 0 0 0 0 0 0 0 14 (12 midges, 2 crane flies) 0 0 0 0
10/25/2013 9 0 0 1 0 0 4 0 3 midges 0 1 riffle beetle (adult) 0 0
7/15/2013 12 0 5 1 0 0 5 0 1 crane fly 0 0 0 0
4/20/2013 100+ 4 aquatic worms 0 1 0 0 0 0 95+ midges 0 0 0 0
10/20/2012 100+ 1 (planaria) 1 0 1 darner dragonfly 0 87+ 0 10+ midges 0 0 0 0
7/31/2012 100+ 13 (planaria) 0 1 3 damselflies (2 narrow-winged, 1 broad-winged) 0 56+ 0 20+ midges 7 (fingernail) 0 0 0
4/25/2012 100+ 3 (planaria) 2 0 0 0 30+ 4 (pond snails) 61+ (60+ midges, 1 crane fly) 0 0 0 0
10/15/2011 32 4 aquatic worms, 2 planaria 9 0 0 0 16 1 (pond snail) 0 0 0 0 0
07/21/2011 100+ 3 5 1 6
(5 darner dragonflies, 1 broad-winged damselfly)
0 20 0 67+ (65+ midges, 2 mosquitos) 0 0 0 0
04/20/2011 100+ 0 17 0 1
(dragonfly)
0 12 0 70+ (67+ midges, 3 crane flies) 0 0 0 0
10/09/2010 100+ 0 1 0 3
(damselflies)
0 100+ 0 11 (10 midges, 1 crane fly) 0 0 0 0
7/06/2010 100+ 2 0 2 0 0 100+ 0 0 6 0 0 0
4/17/2010 68 5 40 0 0 3 (small minnow mayflies) 7 0 13 (10 midges, 3 crane flies 0 0 0 0
10/25/2009 100+ 1 100+ 1 2 (1 damselfly, 1 dragonfly) 0 6 0 1 (crane fly) 0 0 0 0
7/16/2009 54 0 1 0 1 (dragonfly) 12 (small minnow mayflies) 23 1 13 (12 midges, 1 crane fly) 0 0 0 0
3/28/2009 59 0 1 0 1 (damselfly) 0 24 0 33 (32 midges, 1 crane fly) 0 0 0 0
10/18/2008 100+ 2 1 1 7 (damselflies) 0 100+ 0 5 (midge) 0 0 0 0
7/5/2008 55 2 0 2 3 (2 damselflies, 1 dragonfly) 0 41 0 7 (midge) 0 0 0 0
4/5/2008 179 1 4 3 0 0 15 1 (limpet) 155 (151 midges, 3 black flies, 1 crane fly) 0 0 0 0
9/8/2007
(low flow conditions)
0 0 0 0 0 0 0 0 0 0 0 0 0
7/8/2007 26 0 13 1 0 1 (small minnow mayfly) 9 0 2 (1 midge, 1 crane fly) 0 0 0 0
5/11/2007 26 0 16 1 0 0 3 0 6 (3 midges, 2 black flies, 1 crane fly) 0 0 0 0
2/03/2007 15 1 3 0 0 0 4 0 7 (4 midges, 3 crane flies) 0 0 0 0
9/11/2006 60 0 44 1 0 0 11 0 4 (midges) 0 0 0 0
7/10/2006 100 1 5 0 0 0 84 0 10 (9 midges, 1 crane fly) 0 0 0 0

FOSC/NF Biological Monitoring Results

for the Nature Forward Site in Lower Sligo Creek

NATURE FORWARD (formerly Audubon Naturalist Society) – WATER QUALITY MONITORING PROGRAM
BENTHIC MACROINVERTEBRATE DATA for 2 new sites in Prince George’s County
SPRING – SUMMER – FALL 2022
04/02/22 07/10/22 10/30/22 04/16/22 07/23/22 10/16/22
SLIGO CREEK SLIGO CREEK SLIGO CREEK NORTHWEST BRANCH NORTHWEST BRANCH NORTHWEST BRANCH
PHYLUM ORDER (or subclass) FAMILY GENUS COMMON NAME COUNT COUNT COUNT COUNT COUNT COUNT
Annelida Hirudinea Erpobdellidae Leeches (cylindrical) 1
Annelida Oligochaeta Lumbriculidae Aquatic worms 3 4 4 8 3 1
Platyhelminthes Tricladida Dugesiidae Planarians, flatworms 6 2 28 3 2 4
Arthropoda Amphipoda Gammaridae Scuds 2 3 1
Arthropoda Coleoptera Elmidae genus not identified Riffle beetles (adults) 2 1
Arthropoda Coleoptera Elmidae Stenelmis Riffle beetles (adults) 2
Arthropoda Diptera Chironomidae Midges 34 61 7
Arthropoda Diptera Simuliidae Black flies 4 1 1 1
Arthropoda Diptera Tipulidae genus not identified Crane flies 1 3
Arthropoda Diptera Tipulidae Antocha Crane flies 1
Arthropoda Diptera Tipulidae Dicranota Crane flies 1
Arthropoda Diptera Tipulidae Tipula Crane flies 1
Arthropoda Trichoptera Hydropsychidae Common netspinner caddisflies 14 17 28 7 61 42
Arthropoda Trichoptera Leptoceridae Longhorned case maker caddis 1
Arthropoda Trichoptera Philopotamidae Fingernet caddisflies 32 35 39 6 1 33
Arthropoda Trichoptera Polycentropodidae Trumpetnet caddisflies 1
Arthropoda Trichoptera Uenoidae Uenoid case maker caddisflies 1
Arthropoda Ephemeroptera Baetidae Small minnow mayflies 43 2 4 27 12
Arthropoda Ephemeroptera Heptageniidae Flatheaded mayflies 1 1 2
Arthropoda Odonata/Zygoptera Calopterygidae Broadwinged damelflies 3 1 1 3
Arthropoda Odonata/Zygoptera Coenagrionidae Narrowwinged damselflies 1 8
Arthropoda Megaloptera Corydalidae Corydalus Dobsonflies 1 1
Arthropoda Megaloptera Corydalidae Nigronia Fishflies 1
103 103 101 107 110 102
ANS IBI score / Health rating 1.57 / Poor 1.86 / Poor 1.00 / Poor 2.14 / Fair 2.71 / Fair 2.14 / Fair
pH 7.6 + 7.6 + 8.1 7.6 7.6 7.6
Ambient air temperature 10.0⁰ C 27.0⁰ C 17.0⁰ C 26.0⁰ C 32.0⁰ C 14.0⁰ C
Average water temperature 11.0⁰ C 22.8⁰ C 10.7⁰ C 18.0⁰ C 25.3⁰ C 13.6⁰ C
Sites
1. Sligo Creek near the Pepco ROW in Takoma Park (38.976534, -76.986064).
2. Northwest Branch at Riggs Road at the Adelphi Mill Rec Center (38.992694, -76.972954).
Notes
-The collection was subsampled to record 100 specimens (or slightly more based on counting all specimens in the subsampling tray’s cell where the 100th specimen was reached).
-The stream health rating is based on the benthic macroinvertebrate survey.
-We used a high range pH test kit for Sligo Creek for Fall 2022 (our standard test kits have an upper limit of 7.6).
-All macroinvertebrates were returned to the streams.