MBSS Site Summary for: PG-N-163-111-97


Located on BEAVERDAM CR in the Anacostia River watershed, 8-digit code: 02140205.
This stream was visited in the spring on 3/25/1997 and again in the summer on 7/14/1997.

Index of Biotic Integrity (IBI) Results:

An Index of Biotic Integrity (IBI) is a scientific tool used to identify and classify stream health. An IBI associates anthropogenic influences on a stream or with biological condition in the stream, and is formulated using data developed from biosurveys.
Details on the development and application of MBSS IBIs are in this document.
Fish IBI Poor - 2.7 / 5.0
Benthic IBI Poor - 2.4 / 5.0

Land Use

Land use can provide important information for determining stream health.
(Hint: Screen readers will announce definitions; mouse users can hover over dotted text.)
Catchment area 288 acres Cows standing in a stream at a site with high agricultural land use. Cows survey the sampling procedure at this extreme example of a highly agriculturalized site.
Urban Land Use 28.3 %
Agricultural Land Use 37.3 %
Forested Land Use 32.5 %


Stream showing woody debris, logs, and rocky substrate.
An example of woody debris in a stream.

Physical Stream Habitat
Instream Habitat 5/20 (Poor)
Epifaunal Substrate 3/20 (Poor)
Velocity/Depth Diversity 6/20 (Marginal)
Pool Quality
Pool Extent = meters 		3/20 (Poor)
Riffle Quality 6/20 (Marginal)
Shading 95 %
Embeddedness 100 %
The embeddedness, a measure of silt on the stream bottom, was 100%. This is very high, and may adversely affect biotic communities.
Several measures of instream habitat were considered 'Poor' at this location.


Stream Water Quality:
Water temperature 15 ° C
Dissolved oxygen (DO) 7.8 mg/L
pH (lab) 5.91
Conductivity 119 µmho/cm
Alkalinity
(acid neutralizing capacity) 		182 µeq/L
Dissolved organic carbon (DOC) 1.8 mg/L

Biological Stream Condition:

Surveys of the organisms living within a stream can give indications of stream health. Species richness, or the number of different species present, as well as indicator species (species whose presence, absence or abundance can serve as a measure of environmental conditions) are informative for stream health. 		Close-up of a mayfly indicator species.

Fish Survey Results:
The following 3 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Eastern Mudminnow 5
Blacknose Dace 1
Least Brook Lamprey 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Northern Dusky Salamander
Northern Green Frog
Northern Spring Peeper
Northern Two-Lined Salamander

Crayfish:
No crayfish noted.

Exotic Plants:
No exotic plants noted.
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Cricotopus/Orthocladius Midge 48
Caecidotea Isopod 10
Lepidostoma Little Brown Sedge Caddisfly 9
Naididae Aquatic Worm 6
Corynoneura Non-Biting Midges 6
Agabus Predatory Aquatic Beetle 5
Parametriocnemus Non-Biting Midges 4
Krenopelopia Non-Biting Midge 4
Stegopterna Black Fly 2
Dicranota Hairy-Eyed Cranefly 2
Leuctra  Rolled-Winged Stonefly 2
Hyalella Amphipod 2
Micropsectra Non-Biting Midges 2
Cryptochironomus Non-Biting Midges 1
Cordulegaster Spiketail Dragonfly 1
Kick net sampling for macroinvertebrates.
Sampling with a kick net.

Information disclaimer: The information and data on this page is for guidance and general planning purposes only. It should not be used to make decisions on specific matters.