MBSS Site Summary for: PAXL-120-R-2004

Site Photos

Field photo showing stream conditions at site PAXL-120-R-2004-1 (Opens in a new window) Field photo showing stream conditions at site PAXL-120-R-2004-2 (Opens in a new window)

Located on CHEW CR in the Patuxent River lower watershed, 8-digit code: 02131101.
This stream was visited in the spring on 3/3/2004 and again in the summer on 6/17/2004.

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 - 1.7 / 5.0
Benthic IBI Fair - 3.6 / 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 2,355 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 18 %
Agricultural Land Use 41 %
Forested Land Use 41 %


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

Physical Stream Habitat
Instream Habitat 8/20 (Marginal)
Epifaunal Substrate 7/20 (Marginal)
Velocity/Depth Diversity 11/20 (Suboptimal)
Pool Quality
Pool Extent = 70 meters 		11/20 (Suboptimal)
Riffle Quality
Riffle Extent = 75 meters 		15/20 (Suboptimal)
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 19.4 ° C
Dissolved oxygen (DO) 8 mg/L
pH (lab) 7.22
Conductivity 214 µmho/cm
Alkalinity
(acid neutralizing capacity) 		589.3 µeq/L
Dissolved organic carbon (DOC) 1.9 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 6 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Eastern Mudminnow 76
Pumpkinseed 14
Fathead Minnow 8
Bluegill 4
Blacknose Dace 1
Creek Chubsucker 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

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

Crayfish:
No crayfish noted.

Exotic Plants:
Japanese Honeysuckle
Japanese Stiltgrass
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Prostoia Spring Stonefly 27
Gammarus Amphipod 21
Parametriocnemus Non-Biting Midges 17
Thienemannimyia group Non-Biting Midges 11
Rheosmittia Non-Biting Midges 6
Limnephilidae Northern Casemaker Caddisfly 5
Isoperla Stripetail Stonefly 5
Orthocladius Non-Biting Midges 4
Tipula Crane Fly 3
Prosimulium Black Fly 2
Polypedilum Non-Biting Midges 2
Micropsectra Non-Biting Midges 2
Caecidotea Isopod 2
Stilocladius Midge 2
Dineutus Whirlygig Beetle 2
Lumbriculidae Worm 1
Leptophlebiidae Pronggilled Mayfly 1
Macronychus Riffle Beetle 1
Capniidae Small Winter Stonefly 1
Boyeria Spotted Darner Dragonfly 1
Thienemanniella Non-Biting Midges 1
Zavrelimyia Non-Biting Midges 1
Cheumatopsyche Net-Spinning Caddisfly 1
Diplocladius Non-Biting Midges 1
Microtendipes Non-Biting Midges 1
Gomphidae Clubtail Dragonfly 1
Pseudolimnophila Crane Fly 1
Chelifera Aquatic Dance Fly 1
Calopteryx Damselfly 1
Chrysops Deerfly 1
Dicranota Hairy-Eyed Cranefly 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.