Module 10/11 Stream Surveys Stream Surveys – September 2004 Part 2 – Habitat Assessment

Module 10/11Stream Surveys

Stream Surveys – September 2004Part 2 – Habitat Assessment

Developed by: Richards, Reed, Ruzycki Updated: Sept 2004 U3-m10/11b-s2

Objectives

Students will be able to: identify accepted sampling methods used in

streams. explain the influence of velocity and current on

organism distribution in a stream. categorize stream bed substrates. Describe physical, chemical and biological

parameters used to assess the quality of stream habitats.


Stream assessments

Water quality Habitat Hydrologic Biological Watershed


Habitat assessments


Habitat Assessments

Determine and isolate impacts of pollution sources

Interpret biological data Screen for impairments


Habitat Scales - review


Where to sample

Reach Length 30 times mean stream width Minimum of 100 meters in length

Avoid bridges, dams, culverts etc. Localized effects on the stream Both upstream and downstream of the

structure. Locate reach nearby to specifically address

changes from structures


Transect Measurements

Necessity of measuring habitat variables in both pool and riffles and why

Slide to be completed by 3/31/04


Pool-Riffle-Run Sequences


Current velocity

Varies horizontally and vertically across the streambed

Current is the most important factor that determines where many organisms are found in streams and therefore govern differences in communities in various parts of a given stream.

Velocity of the current is determined by the steepness of the surface, roughness of the stream bed, and depth and width of the stream bed.


Substrate


Visual estimation of surface substrate

% of silt/clay, sand, gravel, cobble, boulder and bedrock

Fast, simple Prone to error



Substrate

Sieves Especially for <2mm Sample size = bucketful ~ 3 samples



Substrate - Pebble counts

100 individual pebbles randomly selected from stream bed

Measure intermediate axis Plot results as a

histogram

(Wolman 1954)


Pebble Count results


Embeddedness

Measure of fine sediment deposition in the interstitial spaces between rocks

High embeddedness values indicate habitat degradation


Substrate

Embeddedness: General guidelines 0% = no fine sediments even at base of top

layer of gravel/cobble 25% = rocks are half surrounded by sediment 50% = rocks are completely surrounded by

sediment but their tops are clean 75% = rocks are completely surrounded by

sediment and half covered 100% = rocks are completely covered by

sediment


Wentworth Scale of particle sizes

Silt/clay/mud fine

Sand up to 0.2 cm

Gravel (or pebbles) 0.2 – 6.4 cm

Cobbles 6.4 cm – 25.6 cm

Boulders greater than 25.6 cm

Bedrock Bigger than a car


Woody debris

Extremely important for habitat Difficult to quantify


EPA Rapid Bioassessment Protocols (RBP)

The RBPs include a set of cost-effective, yet scientifically valid, stream quality indicators that include: Physical habitat assessment Water Quality assessment Biological surveys

Easily and quickly obtained

Compares data with standards fromunaffected site


RBP - parameters

Stream characterization Watershed features Riparian vegetation In-stream features Large woody debris Aquatic vegetation Water quality Sediment/substrate


RBP – stream characterization

Is stream flow perennial, intermittent? Are there any tidal influences?

Is the temperature regime considered warm water or coldwater?

Stream origin: glacial, montane, wetland, bog


RBP – watershed features

What is the predominant land use type within the watershed?

Are there any local nonpoint pollution sources?

Any signs of local watershed erosion ?


RBP – riparian vegetation

Width of the vegetation zone on either side of the stream


RBP – in-stream features

reach length stream width reach area velocity % canopy high water mark # riffles, runs, pools channelization dams


RBP – large woody debris and aquatic vegetation

Large woody debris Aquatic vegetation

periphyton macrophytes


RBP – water quality

Temperature, EC, DO, pH, and turbidity

Water odors Water surface oils Turbidity-visual

assessment


RBP – sediment and substrate

Odors Oils Deposits Inorganic substrate

components Organic substrate

components


Visual-Based Habitat Assessment (VHA)

This protocol rates habitat parameters for each sampling reach on a scale from 0 to 20 (highest).

The rankings are then totaled and compared to a reference condition to provide a final habitat ranking.

Habitat evaluations are made on: In-stream habitat Channel morphology Bank structural features Riparian vegetation


VHA - Habitat for aquatic insects and other creatures

Look for the amount and variety of structures in the stream, such as: rocks fallen trees undercut banks logs and branches

The more diverse the “structure” the better.

Poor

Very good


1b. Habitat for Aquatic Insects and Other Creatures Look for:

The amount and variety of structures in the stream, such as:RocksFallen treesUndercut banksLogs and branches

A lot of diverse “structure” is good

Poor

Very good

Mary

Kay C

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MN


2a. Embeddedness

Look for: How much silt, sand, or mud cover rocks and

snags or is “embedded” among the rocks? Lots of silt reduces insect habitat and fish

shelter, spawning areas, and egg incubation areas

Poor

Very good

Will

iam

Taft

, M

I D

NR

Will

iam

Taft

, M

I D

NR

Poor


2b. Pool Substrate Condition

Look for: Type and condition of bottom of stream in

pool area Healthy stream has:

Firm sediment types, such as sand, gravel, rather than soft clay or silt

Aquatic plantsLots of variety

PoorVery good

Mary

Kay C

ora

zalla

, U

of

MN


3a. Velocity and Depth Regimes

Look for: Lots of variety in depths and

flow rates as you move downstream

Look for a combination of: Slow-deep Slow-shallow Fast-deep Fast-shallow

Provides more habitat for aquatic insects and fish

Poor

Mary

Kay C

ora

zalla

, U

of

MN

Very good

Will

iam

Taft

, M

I D

NR

Poor


3b. Pool Variability

Look for: Mixture of types of pools

Large-shallowLarge-deepSmall-shallowSmall-deep

A variety of pool types means good habitatPoor

Very good

Peg

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org

an

, FL

DEP

Will

iam

Taft

, M

I D

NR


4a. Sediment Deposition

Look for: How much sediment

has been deposited in the stream channel as: IslandsPoints, barsShoalsPools filling in

Lots of sediment means lots of human impacts on stream

Very good

Poor

Deposited sediment


4b. Sediment Deposition

How much sediment has been deposited in the stream channel as: IslandsPoints, barsShoalsPools filling in

Lots of sediment means lots of human impacts on stream

Poor

Very good


5a. Channel Flow Status

Look for: How full is the

channel? If too much of the

streambed is exposed, habitat is limited and probably poor

Very good

Water is not reaching both banks; leaving much

of channel exposed.

Poor


5b. Channel Flow Status

How full is the channel? If too much of the streambed is exposed, habitat is limited

and probably poor

Poor

Very good

Water is not reaching both banks; leaving much of channel exposed.

Jam

es

Sta

hl, IN

DEM


6a. Channel Alteration

Look for: Human-caused

changes in the stream channel, such as:DeepenedStraightenedDiversions

These alterations mean less habitat

Very good

Poor


6b. Channel Alteration

Human-caused changes in the stream channel, such as:DeepenedStraightenedDiversions

These alterations mean less habitat

Poor

Very good

Joh

n M

axte

d,

DE D

NR

EC


7a. Frequency of Riffles

Look for: Frequency of riffles as you

look up or downstream Riffles are excellent habitat

for aquatic insects and fish Lots of riffles means good

habitat

Arrows showing frequency of

riffles and bends

Very good

Poor


7b. Channel Sinuosity

Look for: The number of twists and turns you see in

the stream A “curvy” stream

Has more habitatIs more stable during storms, thus reducing erosion

Sinuosity refers to the curviness of the stream

Poor

Very good


8a. Bank Stability

Look for: Condition of banks

No vegetationCrumbling banksOverly steep banksExposed tree rootsExposed soil

Presence of eroded stream banks means poor conditions for aquatic life

Very good

Poor

Stable streambank

Unstable streambank

MD

Save O

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Str

eam

s


8b. Bank Stability

Look for: Condition of banks

No vegetationCrumbling banksOverly steep banksExposed tree rootsExposed soil

Presence of eroded stream banks means poor conditions for aquatic life

Poor

Very good

Peg

gy M

org

an

, FL

DEP


9a. Bank Vegetation

Look for: Amount of vegetation on banks of stream Lots of vegetation

Holds soilsAbsorbs water, thus reducing bank erosionAbsorbs nutrients (through roots) Provides shade for stream

Good to have >90% vegetative cover on banks and in riparian area

Very good

Poor


9b. Bank Vegetative Protection

Look for: Amount of vegetation on banks of stream Lots of vegetation

Holds soilsAbsorbs water, thus reducing bank erosionAbsorbs nutrients (through roots) Provides shade for stream

Good to have >90% vegetative cover on banks and in riparian area

Poor

Very good

Peg

gy M

org

an

, FL

DEP

MD

Save O

ur

Str

eam

s


10a. Riparian Vegetative Zone Width

Look for: Width of riparian zone (vegetated area

adjacent to stream) Wider riparian area helps

buffer pollutantsControl erosionProvide habitatRegulate nutrient inputs

Poor

Very good


10b. Riparian Vegetative Zone Width

Look for: Width of riparian zone (vegetated area

adjacent to stream) Wider riparian area helps

buffer pollutantsControl erosionProvide habitatRegulate nutrient inputs

PoorVery good

MD

Save O

ur

Str

eam

s


2. Low Gradient Streams

Less steep, slower moving

Low gradient streams are dominated by deep areas (pools) interspersed with shallower segments of river (glides). The stream bottom is typically made of up fine sediments and occasional coarser material (gravel or larger).

Low

Gra

die

nt

Str

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Stream surveys - references

Techniques of Water-Resources Investigations Reports http://water.usgs.gov/pubs/twri/

National Field Manual for the Collection of Water-Quality Data http://water.usgs.gov/owq/FieldManual/

Rapid bioassessment protocols for wadeable streams http://www.epa.gov/owow/monitoring/rbp/

Documents

Module 10/11 Stream Surveys Stream Surveys – September 2004 Part 2 – Habitat Assessment