MBSS Site Summary for: PAXL-294-S-2015


Located on SWANSON CREEK in the Patuxent River lower watershed, 8-digit code: 02131101.
This stream was visited in the spring on 3/10/2015 and again in the summer on 6/15/2015.

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 Good - 4.7 / 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 16/20 (Optimal)
Epifaunal Substrate 17/20 (Optimal)
Velocity/Depth Diversity 14/20 (Suboptimal)
Pool Quality
Pool Extent = 50 meters 		17/20 (Optimal)
Riffle Quality
Riffle Extent = 29 meters 		16/20 (Optimal)
Shading 70 %
Embeddedness 85 %
The embeddedness, a measure of silt on the stream bottom, was 85%. This is relatively high, and may exclude some biota.
Several measures of instream habitat were considered 'Optimal' at this location.


Stream Water Quality:
pH (lab) 6.87
Alkalinity
(acid neutralizing capacity) 		185.97 µeq/L
Dissolved organic carbon (DOC) 3.1536 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 14 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Rosyside Dace 141
Blacknose Dace 57
Sea Lamprey 53
Fallfish 34
Tessellated Darter 22
Least Brook Lamprey 16
Eastern Mudminnow 13
American Eel 6
Redbreast Sunfish 6
Creek Chubsucker 3
Tadpole Madtom 3
Golden Shiner 1
Largemouth Bass 1
White Sucker 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Northern Green Frog

Crayfish:
Orconectes limosus

Exotic Plants:
Japanese Stiltgrass
Multiflora Rose
Wineberry
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Ephemerella Sulphur Mayfly 15
Cheumatopsyche Net-Spinning Caddisfly 14
Prosimulium Black Fly 11
Acerpenna Tiny Blue-Winged Olive Mayflies 10
Prostoia Spring Stonefly 7
Hexatoma Crane Fly 6
Optioservus Riffle Beetle 5
Strophopteryx Early Brown Stonefly 4
Neophylax Caddisfly 4
Isoperla Stripetail Stonefly 4
Rheotanytarsus Non-Biting Midges 3
Chloroperlidae Green Stonefly 3
Oulimnius Riffle Beetle 3
Corynoneura Non-Biting Midges 3
Microtendipes Non-Biting Midges 2
Clioperla Green-Winged Stonefly 2
Maccaffertium March Brown And Cahill Mayfly 2
Hemerodromia Tiny Fly 2
Eccoptura Yellow Stone Stonefly 1
Stilocladius Midge 1
Lype Net Tube Caddisfly 1
Physa Air-Breathing Freshwater Snail 1
Gammarus Amphipod 1
Tubificidae Aquatic Worm 1
Paratanytarsus Non-Biting Midges 1
Rheocricotopus Non-Biting Midges 1
Micropsectra Non-Biting Midges 1
Anafroptilum Small Minnow Mayfly 1
Capniidae Small Winter 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.