MBSS Site Summary for: PAXU-102-R-2004

Site Photos

Field photo showing stream conditions at site PAXU-102-R-2004-45 (Opens in a new window) Field photo showing stream conditions at site PAXU-102-R-2004-46 (Opens in a new window)

Located on PATUXENT R UT 11 in the Patuxent River upper watershed, 8-digit code: 02131104.
This stream was visited in the spring on 3/8/2004 and again in the summer on 6/10/2004.

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 1,695 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 10 %
Agricultural Land Use 11 %
Forested Land Use 74 %


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

Physical Stream Habitat
Instream Habitat 16/20 (Optimal)
Epifaunal Substrate 16/20 (Optimal)
Velocity/Depth Diversity 12/20 (Suboptimal)
Pool Quality
Pool Extent = 40 meters 		15/20 (Suboptimal)
Riffle Quality
Riffle Extent = 35 meters 		10/20 (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.


Stream Water Quality:
Water temperature 21 ° C
Dissolved oxygen (DO) 7.2 mg/L
pH (lab) 6.17
Conductivity 88 µmho/cm
Alkalinity
(acid neutralizing capacity) 		65.6 µeq/L
Dissolved organic carbon (DOC) 4.1 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 4 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
American Eel 8
Eastern Mudminnow 4
Bluegill 3
Tessellated Darter 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
American Bullfrog
Eastern Cricket Frog
Eastern Gartersnake
Eastern Red-Backed Salamander
Eastern Wormsnake
Gray Treefrog
Northern Green Frog
Southern Leopard Frog

Crayfish:
No crayfish noted.

Exotic Plants:
Japanese Stiltgrass
Mile-A-Minute
Multiflora Rose
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Stegopterna Black Fly 49
Cheumatopsyche Net-Spinning Caddisfly 14
Thienemannimyia group Non-Biting Midges 10
Parametriocnemus Non-Biting Midges 8
Simuliidae Black Fly 8
Simulium Black Fly 6
Limnephilidae Northern Casemaker Caddisfly 6
Hydropsyche Net-Spinning Caddisfly 5
Caecidotea Isopod 4
Crangonyx Amphipod 4
Crangonyctidae Scud 3
Conchapelopia Non-Biting Midges 2
Prosimulium Black Fly 2
Hexatoma Crane Fly 2
Tipula Crane Fly 2
Muscidae Fly 1
Orthocladius Non-Biting Midges 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.