MBSS Site Summary for: PAXL-294-S-2014

Site Photos

Field photo showing stream conditions at site PAXL-294-S-2014-MidpointDownstream (Opens in a new window) Field photo showing stream conditions at site PAXL-294-S-2014-MidpointUpstream (Opens in a new window)

Located on SWANSON CREEK in the Patuxent River lower watershed, 8-digit code: 02131101.
This stream was visited in the spring on 3/31/2014 and again in the summer on 6/25/2014.

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 Fair - 3.7 / 5.0
Benthic IBI Good - 4.7 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 3,723 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 9.7 %
Agricultural Land Use 19.1 %
Forested Land Use 68 %


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

Physical Stream Habitat
Instream Habitat 11/20 (Suboptimal)
Epifaunal Substrate 10/20 (Marginal)
Velocity/Depth Diversity 12/20 (Suboptimal)
Pool Quality
Pool Extent = 48 meters 		14/20 (Suboptimal)
Riffle Quality
Riffle Extent = 27 meters 		13/20 (Suboptimal)
Shading 60 %
Embeddedness 80 %
The embeddedness, a measure of silt on the stream bottom, was 80%. This is relatively high, and may exclude some biota.


Stream Water Quality:
pH (lab) 6.77
Alkalinity
(acid neutralizing capacity) 		145.7 µeq/L
Dissolved organic carbon (DOC) 4.734 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 11 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Blacknose Dace 67
Rosyside Dace 45
Tessellated Darter 27
Fallfish 16
Eastern Mudminnow 7
American Eel 5
Least Brook Lamprey 3
Sea Lamprey 3
Redbreast Sunfish 2
Tadpole Madtom 2
White Sucker 2
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Eastern Cricket Frog
Northern Green Frog
Northern Spring Peeper
Pickerel Frog

Crayfish:
Orconectes
Orconectes limosus

Exotic Plants:
Japanese Honeysuckle
Japanese Stiltgrass
Mile-A-Minute
Multiflora Rose
Privet
Wineberry
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Prosimulium Black Fly 20
Ephemerella Sulphur Mayfly 16
Acerpenna Tiny Blue-Winged Olive Mayflies 6
Isoperla Stripetail Stonefly 6
Orthocladius Non-Biting Midges 6
Prostoia Spring Stonefly 5
Simulium Black Fly 4
Strophopteryx Early Brown Stonefly 3
Cheumatopsyche Net-Spinning Caddisfly 3
Tvetenia Non-Biting Midges 3
Leuctridae Rolledwinged Stonefly 3
Physa Air-Breathing Freshwater Snail 2
Oulimnius Riffle Beetle 2
Eukiefferiella Non-Biting Midges 2
Microtendipes Non-Biting Midges 2
Rheocricotopus Non-Biting Midges 2
Maccaffertium March Brown And Cahill Mayfly 2
Nigronia Megaloptera (Dark Fishfly) 1
Hydrobaenus Midge 1
Haploperla Green Stonefly 1
Dolichopodidae Long-Legged Fly 1
Neophylax Caddisfly 1
Hexatoma Crane Fly 1
Rheotanytarsus Non-Biting Midges 1
Trissopelopia Non-Biting Midges 1
Parametriocnemus Non-Biting Midges 1
Paraphaenocladius Non-Biting Midges 1
Diplectrona Net-Spinning Caddisfly 1
Hydropsyche Net-Spinning Caddisfly 1
Ancyronyx Spider Riffle Beetle 1
Hydatophylax Northern Caddisfly 1
Perlodidae Perlodid Stonefly 1
Optioservus Riffle Beetle 1
Eccoptura Yellow Stone Stonefly 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.