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STREAM SUBSTRATE QUALITY FOR SALMONIDS: GUIDELINES FOR SAMPLING, PROCESSING, AND ANALYSIS (Perpetual Draft--January 4, 1995) 1 Bradley E. Valentine Regional Biologist California Department of Forestry and Fire Protection Coast Cascade Regional Office P.O. Box 670 Santa Rosa, CA. 95401 (707) 576-2937

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Page 1: stream substrate quality for salmonids - StreamNet Regional Library

STREAM SUBSTRATE QUALITY FOR SALMONIDS:

GUIDELINES FOR SAMPLING, PROCESSING, AND ANALYSIS

(Perpetual Draft--January 4, 1995)1

Bradley E. ValentineRegional Biologist

California Department of Forestry and Fire ProtectionCoast Cascade Regional Office

P.O. Box 670Santa Rosa, CA. 95401

(707) 576-2937

I intend to continue refining and updating this document as new information becomes available. Citations should be included in the draft

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TABLE OF CONTENTS

WHO & WHY? . . . . . . . . . . . . . . . . . . . . . . . . . 1

HOW? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2Sample Extraction . . . . . . . . . . . . . . . . . . . . 2Sieve Analysis . . . . . . . . . . . . . . . . . . . . . 2

WHAT? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Sample Metrics . . . . . . . . . . . . . . . . . . . . . 5Percent Finer . . . . . . . . . . . . . . . . . . . . . . 5Geometric Mean . . . . . . . . . . . . . . . . . . . . . 6Fredle index . . . . . . . . . . . . . . . . . . . . . . 6Correction Terms . . . . . . . . . . . . . . . . . . . . 6

Statistics . . . . . . . . . . . . . . . . . . . . . . . . . 7Number of Samples . . . . . . . . . . . . . . . . . . . . . . 7

WHERE? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Entire Channel Conditions . . . . . . . . . . . . . . . . 8Redds . . . . . . . . . . . . . . . . . . . . . . . . . . 8Pool / Riffle Breaks .. . . . . . . . . . . . . . . . . . 8

WHEN? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

SO WHAT? . . . . . . . . . . . . . . . . . . . . . . . . . . 10

ACKNOWLEDGMENTS . . . . . . . . . . . . . . . . . . . . . . . 11

REFERENCES CITED . . . . . . . . . . . . . . . . . . . . . . 12

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STREAM SUBSTRATE QUALITY:GUIDELINES FOR SAMPLING, PROCESSING, AND ANALYSIS

(Perpetual Draft--January 4, 1995)

WHO & WHY?

Agencies mandated to 1) protect the beneficial uses of thestate’s waters (Regional Water Quality Control Board), 2)conserve the State’s fish and wildlife (Department of Fish &Game), and 3) provide environmental protection oversight duringtimber harvests on private and state lands (CaliforniaDepartment of Forestry) are concerned about land use practicesthat accelerate the rate at which upslope materials areintroduced to streams during timber harvest activities. Privatetimber companies and independent operators own and conducttimber harvest on large areas draining into the state’s spawningstreams. The State’s concern multiplies in highly erodiblewatersheds where there have been / are to be large portionsharvested in short periods and / or the watershed ischaracterized by highly erodible materials, especially finesediments.

To carry out the mission of the agencies mandated to protectthe state’s water-related resources from sediment impacts, thestate may ask project proponents to assess the condition of astream’s salmonid habitat. The form of sediment impacts towatercourses from land use activities is heavily dependent ongeology (Lisle, pers. commun.), and thus the potential impacts

should be considered when deciding which measurement tools touse. Lisle and Eads (1991) review several methods to measuresedimentation of stream channels with special emphasis onspawning gravels. Recent research (Knopp 1993) has investigatednew methods to evaluate the effects of forest practices on thestructural conditions of habitat. His results indicate that themeasures V-star (the amount of fine sediments accumulated inpools), RASI (Riffle Armour Stability Index, which measures thecomposition of riffle-surface sediments), and D50 median particlesize of riffle gravels) could distinguish between watercoursesdraining unharvested watersheds and all other categories ofwatershed disturbance. However, the variables were less able todiscriminate among streamcourses draining watersheds harvestedeither 1) greater than 40 years ago with no interveningactivity, 2) those harvested more recently under either moderateupslope disturbance, or 3) those harvested with heavydisturbance.

An older and more "standard" measure of the impacts ofupslope disturbance to cold water fish habitat is an evaluationof the substrate’s particle-size distribution, long known forits relationship to spawning success and productivity of aquaticmacroinvertebrates. Agencies may ask landowners to perform thisanalysis when concerns are expressed, or landowners may want todevelop their own monitoring program. The purpose of thisdocument is not to support or reject any particular process toevaluate sediment impacts to streams. Rather, it is to provide

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guidelines to parties requested by the state (through reviewteam or other functions) -- or who chose to do so on their ownvolition -- to evaluate or monitor the stream beds on lands theymanage with a stream-bed, grab-sample approach. This quidancegenerally follows that of Klamt (1976).

HOW?

Sample Extraction

Bulk samples of the substrate are collected with a McNeilsampler (McNeil and Ahnell 1964). Because the potential for biasincreases as the size of materials sampled increases, thediameter of the sampler’s core should be 2-3 times the largestparticle usually encountered (Shirazi et al. 1981); the 6 inchdiameter of Fig. 1 should be considered a minimum. A secondapproach to evaluate the appropriateness of sampler size is totest that the largest particle is < 5% of the total sample(Lisle and Eads 1991). Reports should provide a description ofthe dimensions (diameter and height) of the sampler used.

Recent research in Wyoming has showed that a 20 cm. wide,24 cm long’shovel performed equally well or better than othermethods in portraying the known size distribution of gravel inlaboratory conditions (Young et al. 1991) and field conditions(Grost et al. 1991). Until further evaluated by agency personnelon the North Coast of California, and this guidance document isamended, the McNeil sampler remains the recommended approachbecause of the need to retain comparability with historicvalues.

The sampling tube of the McNeil sampler is manually workedinto the substrate until the bottom of sample basin contacts thechannel. The contents of the sampling tube are removed by handand placed in the basin. The water remaining in the tubecontains suspended material and must be removed with theplunger. The cork is removed from the plunger, the water in thetube agitated with the hand, and the plunger pushed down to themetal stop-pins. The plunger is then tightened by turning thehandle. The cork is replaced and the sampler removed from thestreambed. The contents (including the water and fines in thetube are transferred to a bucket pending sieve analysis.

Sieve Analysis

Particle size analysis of the sample can take severalforms. Dry-sieving involves returning the samples to a lab andfollowing its own protocol. Therefore, it is usually onlyperformed when the highest control on measurement error isrequired; e.g., research situations. The more common method iswet-sieving in the field, which this guidance addressees. olderresearch employed fewer sieves of a wide variety of meshes, thusvarious particle sizes have been related to substrate quality.To help alleviate this variability., more recent research(Shirazi et al. 1981) has recommended using a series of sievesfollowing a geometric progression (e.g., 128, 64, 32, 16, 8, 4,2, 1, 0.5 mm). The upper limit (128 mm) approximates the largestsize

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Particle in which most salmonids will spawn (Platts et al.1983). To facilitate comparison with much of the older researchemployed other sized sieves, other sizes may be added into theseries (e.g., 0.85, 2.36, 3.35, and 4.75 mm), with especiallythe 0.85 mm sieve recommended. Alternatively, the values forthese size. classes can be determined either graphically byplotting the cumulative percent retained, or mathematicallybased on the assumption that stream sediments are lognormallydistributed (Platts et al. 1979).

From the buckets, samples are passed through the series ofsieves using hand shaking and washing with water. Whileagitating the sample by hand in a sieve is useful in the sortingactivity, use care not to force materials through the sievebecause you will bias your sample towards finer condition andmay compromise the usefulness of the sieve if the mesh ispermanently deformed . The trapped sediment on each sieve isallowed to drain and is poured into a partially-filled graduatedcylinder. The volume of particles within that size range is thedifference between the cylinder’s volume before and after addingthe particles.

The sediments passing through the finest mesh screen (intothe "pan") are poured into Imhoff cones (many samples require asmany as five cones to handle the samples water content) and thesuspended material permitted to settle for exactly 10 minutes.The volume (ml) of fines is read directly from the cone. Forconvenience and to minimize the number of settling cones, thevolume of water used to wash samples can be minimized by usingthat water collected with the sample.

Particles retained by the largest sieve (128 mm) are not’included in the calculation of the sample’s metrics. However,their presence or absence should be indicated. The reasons forexcluding these larger materials are 1) larger particles mayexceed the size in which most salmonids will spawn (Platts etal. 1983), 2) the presence or absence of unusually largeparticles can greatly affect the relative proportions of theother size classes (Young et al. 1991), 3) calculation of thegeometric mean particle size requires the calculation of adiameter midpoint for materials retained in a sieve -- withoutthe upper limit, a size larger than the screen must bearbitrarily designated 2 , and 4) larger particles can exceed thediameter of the graduated

2 An alternative approximation of the geometric mean (Shiraziet al. 1981), calculated as:

where dµ and d16 = diameter at the 84th and 16th percentile,

respectively, may avoid the problem if dµ ≤ the largest meshedsieve. However, if dµ ≥ the largest sieve used, its exact valueis indeterminable also.

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cylinders, thus requiring the particle to be broken in order tomeasure. Breaking the particle often induces loss of pieces whenshattered, and thus adds variability to the measure.

Regardless of the size of the largest F articles sampled,measure the length of the intermediate axis of the three largestparticles in each sample. This information enables an analysisof the adequacy of the sampler core. If the frequency of samplesin which the intermediate axis of the largest particles are >h the diameter of the sampling core, a larger sampler isindicated.

Consistency in performing the sieving and measuring processis important in order that the variability is minimized (andthusthe number of samples necessary to characterize the substrate).Following are some hints:• Minimize the amount of water in samples by 1) using squirt bottles to help rinse particles from the sampler into the storage bucket and using sample-water to rinse particles through the sieves.• The volume of water can be reduced, and transporting sample buckets to a central processing location can be eased if upon placing the sample into the bucket from the sampler the bucket is allowed to sit ~: 30 minutes and then about 1/2 of the standing water above the gravel is carefully decanted off the sample.• Each sample being processed should have its own "working area" to avoid interchange sub-samples between samples.• Before performing any of the volumetric displacements of a sample, sieve the entire sample.• Place each sieve with its collected sample at an angle. This accelerates drainage of excess water.• Place the sieves as described above, as much as possible, in the sun.• For materials < 4.0 mm, allow = 10 minutes drip-drying time by allowing these sieves to stand for the entire 10 minute time required for the-settling cones.• Materials < 4.0 mm which still show excessive water retention after 10 minutes can be further drained by placing in a small plastic bag, hand condensed, and the water decanted.• Use the smallest graduated cylinder that can handle the sample portion of interest.• For samples with substantial loads of fines (that in the pan), hand spreading the settled fines between the number of Imhoff cones necessary to handle the water (as opposed to placing most of it in one cone) will reduce volume estimate errors by causing the fine/water zone of contact to fall

The intermediate axis is that which controls what meshsieve the particle could pass. It is the widest dimensionwhich is perpendicular to the particle’s longest dimension.

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within the region of the cone with the finest volumeresolution.

• Having multiple sets of sieves can enhance the number ofsamples simultaneously processed.

• (An) Additional sieve(s) of the largest mesh can act as"extension walls" for sieves of smaller mesh when the volumeof a given sample-fraction is larger than convenientlymanipulated by the sieve alone.

• Having at least two sets of most of the items per sampleprocessed at a time helps speeds sample processing.The volume of each sample fraction is recorded on the data

sheet, along with other supportive information. Comments onlocation, proximity to a suspected redd, sample point conditions(e.g., rooted aquatic vegetation, embedded woody material,presence of clay layers or rocks too large to sample) should berecorded, as well as stream, date, and sampler information.

WHAT?

Sample MetricsThe results of substrate sampling have several potential

forms of expression. Older analysis presented the results as thepercent of a sample less than a given size (e.g., Klamt 1976).Now, other metrics of substrate quality have gained favor(Platts et al. 1983, Chapman 1988, Young et al. 1990) becausethey 1)improve the ability to compare results among studies, and2)provide a fuller measure of the substrate’s physicalconditionsand biological functions. To facilitate comparisonwith olderresults, and to assure continued interpretation, theresultsshould be expressed in three forms: 1) Percent finer, andgraphically, 2) the Geometric Mean, and 3) the Fredle Index.4 Thevolume of materials collected on each sieve is determined andrecorded on the data sheet (see Appendix 2). Within a sample,these are then summed and each sample fraction is divided by thetotal to derive that sieve’s percent of sample retained.

Percent Finer.--- From the sample’s volume-retained value byeach sieve / pan, the percent finer for any sieve size employedis easily calculated by tabulating the cumulative percent of thesample passed figure (See Table 1 for an example). Such a tablewill explicitly indicate the percent of a sample finer than eachsieve employed, enabling others to assess or use theinformation. The 0.85 particle size is-frequently used to define"fines" and should be explicitly presented. When the sieveseries employs the 0.85 mm sieve, the table will present thevalue measured. If the 0.85 mm sieve is not used, than thepercent retained can be

4 A BASIC computer program to calculate these values is available. Toobtain a copy, contact the author on this report’s title page.

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calculated mathematically by assuming the sample is lognormallydistributed. If the full series of sieves is employed, a simplearithmetic extrapolation between the percent retained in the 0.5and the 1.0 sieve will likely be accurate enough. Each sampleshould be graphed (see example in Fig. 1), and the percent finerthan the 0.85 mm size can be estimated using a perpendiculartriangle based at the desired size on the x axis.

Geometric Mean.-- The geometric mean is a measure of centraltendency of the sample calculated.using the size distribution ofthe entire sample. Following the methods described by Lotspeichand Everest (1981), the geometric mean is calculated as:

where:dg = the Geometric mean,d = midpoint diameter of particles retained by a

given sieve and the next larger sieve,w = decimal fraction by volume retained by a

given sieve, . andn = the number of sieves used, inclusive of the

pan.

Fredle Index.- The Fredle Index (Fis a value whichcharacterizes a sample by both its central tendency and ameasure of its distribution. It is calculated following:

where:

dg = the geometric mean as calculated previously, and

d75 and d25 = the particle size diameters at which 75or 25 percent, respectively, of thesample is finer on a volume basis, asestimated from the graphs or from amathematical calculation assuming alognormal distribution.

Correction Terms.- Some investigators have applied correctionterms to the results of sample processing. This is due to 1) thefact that the amount of water retained in a fraction of a sampleis negatively correlated with particle size and becomessignificant below 4.0 mm, and 2) the spawning action of fishwinnows fines from the substrate, thus resulting in a

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coarser gravel distribution in a redd as opposed to the adjacentstreambed. Because 1).the correction factor required for waterretention is dependent on rock type (e.e., the rock density,clay content, etc.), 2) the amount of cleansing accomplished bya spawning fish varies based on factors such as fish size, rockdensity, water velocity, and surrounding substrate conditions,and 3) many older research results did ’ not subject their workdata to correction factors, this guidance recommends that anyresults be presented without corrections, or if corrected, thenboth values presented. If corrected values are also presented,then the correction functions need to be clearly described andjustified. To ensure comparability when comparing your resultswith other’s data, report whether their results were correctedor not, and if so, what correction factors they used.

Statistics.

Sample metrics can be summarized using means, standarddeviations, standard errors and / or confidence intervals.Differences among groups of samples (different streams, siteswithin streams, or years) can be determined following Analysisof Variance tests, or comparable non-parametric test (e.g.,Kruskal- Wallis Test). Standard statistical texts can beconsulted to direct hypothesis testing on sample metrics.

Number of Samples.

The number of samples necessary to characterize a stream ormake comparisons is largely a statistical question, based on thesample’s variance, how certain the agencies must be in detectinga difference, how much difference must be detected, and thesignificance level (α) desired for a test. At a minimum, 10samples should be used. Standard statistical texts can beconsulted on methods to evaluate sample size.

WHERE?

The question of "where" to sample must consider the"universe" to which the results are to apply, and how theresults are going to be used. Defining the universe isimportant, as it determines what can be ascertained from thesampling efforts. Generally speaking, because sedimentation,offines is less of a problem as stream gradient increases, bulksampling of the substrate should be limited to locations whereboth gross (as measured on a USGS quad) and site (as measured inthe field with the sampling location 1/2 the distance betweenthe upstream and downstream reach > 5x the full channel width)gradient are less than 3%. Streams to be sampled should berestricted to those that are 5th order or smaller, as orderedusing bluelines on USGS quads. Examples of sampling universesfor substrate characterization follow.

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Entire Channel Conditions.

If the universe to which the results are to applied is theentire stream bottom, then a random sampling scheme should bedeveloped in which all of the bank-full channel is subject tosampling, regardless if the point is outside the water, in apool, or in a riffle at the time of sampling. Such a scheme maytell much about the characteristics of the stream bottom intotal, but will not be useful in evaluating spawning habitatconditions or to some extent, the amount of stream-generatedfood. This is because such sampling may occur in locations thateither are infrequently wetted for a period adequate for fry toemerge, in locations in the channel in which salmon are unlikelyto spawn (pools), and the invertebrates produced and availableto salmon vary based upon aquatic habitat type and its frequencyand duration of inundation. Use of the quality comparisons basedon standards taken from redds is entirely inappropriate whenthis sampling universe is selected.

Redds

If the sampling universe is salmonid redds, then samplingshould be conducted in randomly sampled redds after young haveemerged. Because the size distribution of gravel can deterioratesubstantially between egg laying and fry emergence (Lisle andLewis 1992), waiting until emergence allows the conditions ofthe intragravel environment to be assessed. This will best allowstatements about the quality of the spawning gravel as relatedto productivity. Waiting until after emergence further avoidsunnecessary mortality. However, because of the inability to knowwhen likely dates of emergence and variable flow conditionsduring that season, sampling redds is problematic. Samplingredds will best allow your sample to be compared with theresults of others who have evaluated the relationship betweensubstrate composition and survival to emergence. However, fewlocal studies have done so. Use of the "relevance" section’squality indicators for samples from this universe is mostappropriate.

Pool / Riffle Breaks

These guidelines recommend collecting one bulk sample fromthe thalweg (deepest part of the stream) at a point near wherethe water begins to accelerate as it passed from a pool into thehead of a riffle. A random sampling criteria for selecting whichpool / riffle break to sample would be statisticallyappropriate. However, due to the logistics of collecting andtransporting samples to a processingstation, some restriction topoints of access (road crossings) is an acceptable deviation(this constraint applies to all sampling universes). The pointof access can function as the center point, with samples beingcollected each n6 pool riffle break upstream and downstream, wheren is a random number between 0 and 5. This deviation from randomsampling for logistic justifications may bias samples towardsfiner substrates if the roads are actively draining into

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the stream. In this case, comparing samples from downstream andupstream of the crossing may elucidate this potential problem.

Restricting the sampling universe to pool / riffle breaksis recommended because 1) salmonids preferentially select sitesto spawn near the tail of a pool or at the head of a riffle (Fry1979, Bjornn and Reiser 1991), 2) the water velocity is commonlygreater at this point during low flow periods thus reducing theimpacts of low-flow period sampling on summer accumulations offines, and 3) for comparative purposes -- others haveapproximated it (Burns 1970, 1972) in regional studies. Thus,such a sampling scheme’s results are related to conditions fromwhich salmonids are likely to choose to spawn, but not to reddsper sel. Randomization enables the results to be extended to allportions of the reach which meet the gradient and stream ordercriteria, as well as enhances the theoretical basis forstatistical tests.

Sampling under this scheme will allow limited comparisonswith other researcher’s findings regarding the relationshipbetween substrate condition and survival to emergence to alimited extent. Because this scheme does not sample from reddswhich would have some fines winnowed by the action of spawning,your samples’ true value is likely to be greater than those ofresearchers who report on conditions within redds. Furtherrestricting sample location to those used by spawning fish willmake comparisons with research data more appropriate. Forexample, Reeves et al. (1989) indicate that coho salmon spawninghabitat should be 1) dominant gravels between-1 and 20 cm (aboutpea to orange size) 2) of a contiguous area at least 2 M2.

If the purpose of sampling is for monitoring, randomizationof sampling points will alleviate possible sampling-inducedalterations in the sampling universe (See discussion below under"When1l).

A final consideration for locating sampling stations is toattempt to associate the results with either historic sedimentstudies or with other projects. Co-locating your sedimentsampling universe within stream reaches used by others (e.g., afish population sampling station, Burns’ study reaches) canprovide useful information about fish habitat potential and howit has changed on-site. However, this criteria will limit theextent of the universe to which your results can be extended tothe vicinity of that site. Extension to larger areas should bepracticed with caution.

Whatever sampling universe you select, its clear definitionin your report is very important.

WHEN?

If the sampling universe is the entire stream channel,samples should be collected during the summer low-flow period tominimize logistic and sampling difficulties associated with deepand fast flows.

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If the sampling universe is redds, sampling should followsoon after young have emerged. Prior to that time, substratesshould not be sampled to avoid unnecessary killing of fish, andto be able to evaluate conditions during the entire period ofintragravel development.

If the sampling universe is the pool / riffle locations,sampling should be done during the summer low f low period. Thistiming avoids the high-f low problems. Late summer samples maybe sensitive to sediment accumulation between fry emergence andsediment sampling. However, this condition is minimized becausethe pool / riffle interface is a hydraulic location ofrelatively high water velocity, even during the low flow period.

A final consideration in determining when to sample is thestudy’s purpose. Timing may be less important if a one-time,snap-shot of sediment condition is the goal. If the results areto be compared to those of others, then you should attempt tosample during a similar portion of the hydrograph as did they.If your purpose is to monitor (evaluating trends over time(years)), then the sampling period should be repeatable at eachtime when sampling is projected. Frequency of sampling for amonitoring program should take into account annual variabilityand sediment loads in the stream in question; additionalguidance should be sought from the responsible agencies. Inevaluating the sampling frequency, the potential that samplingwithout replacement in stream systems which are supply-limitedfor gravel (>=10 mm) could result in declines in the substrate’ssize distribution should be considered. This hazard would begreater in a sampling regime which sampled the same locationeach year for a number of years, and would be least important ifthe sampling regime was fully randomized.

Should shovels become the standard sampling tool, samplingduring the extreme low-flow period is mandated because higherwater velocity will bias the sample toward a higher than "true"average particle size (Grost et al. 1991, Young et al. 1991).

SO WHAT?

Research has shown that excessive erosion and land-slidingcan limit fish populations -- most notably anadromous salmonids-at several times in the species’ life cycles. Among the impactsare 1) in-filling of pools which reduce the volume and qualityof living space for over-summering parr, and 2) reduction inaverage size of stream substrate which reduces spawning successand restricts the fishes’ food base. In particular, research hasfocused on the relationship between substrate particle size andegg-to-fry survival to emergence.

For your results to provide some relevance, they can becompared to the results of others. For percent fines, Lisle andEads (1991) review of the literature notes that thresholds ofconcern fall most commonly around 20%. Drawing on the data ofothers, Chapman (1988) portrays the relationship between the

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survival to emergence of several salmonid species and thegeometric mean (Fig. 3A) and the Fredle Index (Fig. 3B). Yetanother method (Tappel and Bjornn 1980) is to use a graphicaldepiction based on the percent of a sample finer than two sizeintervals (Fig 5).

Most standards, including those described in the previousparagraph, are based on spawning environments. Therefore, anyassessment of condition must recognize the difference betweenits sampling location protocol and the standards.• Sampling from redds after emergence is the most applicable use of the standards.• Using the standards to judge conditions when samples are collected from the pool / riffle juncture will provide a "worse case" assessment. The survival to emergence value from your samples when compared to the standards will be a conservative estimate of survival; i.e., if the estimate is 404, the true value will be 2: 40%.• When sampling is fully randomized across and along the stream channel and is unrelated to spawning sites, the criteria provided above are not applicable. While coarser is better, the results of such a sampling scheme have not been related by research with any parameters of fish populations.

Two parameters of the substrate are important: condition andtrend. The procedures provided in these guidelines, applied at asingle time, enables reviewers to assess condition. Currentcondition can be variable due to localized natural geologicevents, historic land uses, current land uses, and short- (1-5year) to long-term (decade ±) climate conditions. Relative toland-use decisions, interpretation of the significance of"condition" is complicated by this inherent variability. Evenshort-term conditions may be critical when the population of aspecies (be it fish or of another taxa) which is sensitive tosubstrate character is extremely low. However, generally trendis of greater significance than a "snap-shot" of currentcondition. Repeated application of these guidelines over timewill enable trend to be assessed.

ACKNOWLEDGMENTS

This draft was greatly improved by reviews of earliereditions by Robert Klamt and Charles Green of the Regional WaterQuality Control Board, North Coast Region; Pete Cafferata andMartin Berbach of the California Department of Forestry and FireProtection, Naomi Owen (Sonoma State University), and Tom Lisle(Redwood Sciences Lab, Pacific Southwest Forest and RangeExperiment Station, USDA Forest Service). Comments have beensolicited, but not yet received from Ted Wooster, Rick Macedo,Dick Moore, and Wendy Jones (Dept. Fish & Game, Reg. 3), andChris Knopp (Six Rivers National Forest).

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REFERENCES CITED

Bjornn, T.C., D.W. Reiser. 1991. Habitat Requirements ofSalmonids in Streams. In W.R. Meehan (Ed.) Influences ofForest and Rangeland Management on Salmonid Fishes and TheirHabitats. Am. Fish. Soc. Spec. Publ. 19:83-138.

Burns, J.W. 1970. Spawning Bed Sedimentation Studies in NorthernCalifornia Streams. Calif. Fish & Game 56(4): 253270.

1972. Some Effects of Logging and Associated RoadConstruction on Northern California Streams. Trans. Am. Fish.Soc. 101(l): 1-17.

Chapman, D.W. 1988. Critical Review of Variables Used to DefineEffects of Fines in Redds of Large Salmonids. Trans Am.Fish. Soc. 117:1-21.

Fry, D.H., Jr. 1979. Anadromous Fishes of California. Departmentof Fish & Game. 112 pp.

Grost, R.T., W.A. Hubert, and T.A. Wesche. 1991. Field Comparisonof Three Devices Used to Sample Substrate in Small Streams.N. Am. J. Fish. Manage. 11:347-351.

Klamt, R.R. 1976. Stream Substrate Sampling with the McNeilSampler. Unpubl. Rep. North Coast Regional Water QualityControl Board. Santa Rosa, CA. 1 pp + attachments.

Knopp, C. 1993. Testing Indices of Cold Water Fish Habitat. FinalReport. North Coast Regional Water Quality Control Board.Santa Rosa, CA. 56 pp.

Lisle, T.E. 1994. Personal communication; review of the October1993 version.

and R.E. Eads. 1991. Methods to Measure Sedimentation ofSpawning Gravels. USDA For. Serv. Res. Note PSW-411. 7 pp.

, and J. Lewis. 1992. Effects of sediment transport on survivalof salmonidembryos in a natural stream: a simulation approach.Can. J. Fish. Aquat. Sci. 49(11):23372344.

McNeil, W.J., and W.H. Ahnell. 1964. Success of Pink SalmonSpawning Relative to Size of Spawning Bed Materials. U.S.Fish & Wildl. Serv. Spec. Sci. Rep. Fish. 1469. 15 pp.

Platts, W.S., W.F. Megahan, and G.W. Minshall. 1983. Methods

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for Evaluating Stream, Riparian, and Biotic Conditions. USDA, For.Serv. Gen. Tech. Rep. INT-138. 70 pp.

, M.A. Shirazi, and D.H. Lewis. 1979. Sediment particle sizesused by Salmon for Spawning with methods for Evaluation.EPA-600/3-79-043. US EPA, Environ. Res. Lab., Corvallis,, OR. 33 pp.

Reeves, G.H., F.H. Everest, and T.E. Nickelson. 1989.Identification of Physical Habitats Limiting the Productionof Coho Salmon in Western Oregon and Washington. USDA For.Serv. Gen. Tech. Rep. PNW-245. 18*pp.

Shirazi, M.A., W.K. Seim, and D.H. Lewis. 1981. Characterizationof Spawning Gravel.and Stream System Evaluation. Pp 227-278Xn Cassidy (Dir.). Salmon-spawning Gravel: A Renewable Resourcein the Pacific Northwest? Wash. Wat. Res. Center. Rep. No.39.

Tappel, P.D., and T.C. Bjornn. 1980. Effects of sedimentcomposition on salmonid egg survival. Unpubl. An. Rep(1979-80) to US For. Serv., Intermountain For. and RangeExper. Stat. 20 pp.

Young, M.K., W.A. Hubert, and T.A. Wesche. 1990. Fines in reddsof large salmonids. Trans. Am. Fish. Soc. 119:156-162.

, W.A. Hubert, and T.A. Wesche. 1991. Biases associated withfour stream substrate samplers. Can. J. Fish. Aquat.Sci.48(10):1882-1886.

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Table 1. Example of the cumulative percent table

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Fig. 1. TheMcNeil

samplerKlamt 1976).The samplingtube of themain unit(upper

rted illustration)into thesubstrateuntil thebottom of samplingbasin (angleportion) hitsthe streambed.Materialsdown to thestop pins areexcavatedfrom the

sampling tubeby hand intothe basin.Water in thesampling tube’is agitatedby hand, the

plunger (lower illustration) is placed into

sampling tube until it sits on the pins,

the stopper is inserted to seal in the aqueous portion of thesample, and the sample is removed to a bucket. The 6 inchdiameter for the sampling core is a minimum, some expertsrecommend 12 inch cores.. When altering the designing, the basinvolume must be enlarged to the same capacity as the samplingtube.

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Fig. 2. Example of particle-size distribution graph.

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Fig. 5. Isoclines of the ’Survival to emergence for Steelheadtrout based on two data points (% < 0.85 and % < 9.5 mm) in thecumulative particle size distribution graph. Data isapproximated from Tappel and Bjornn (1983).

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APPENDIX IRecommended Supplies and Materials

The following supplies and materials are recommended for eachsample processing crew. one person is able to process a sample,but an additional person can accelerate the processing time.

Data Sheets (helpful if on waterproof paper)/ Maps / ClipboardIndelible pen.

McNeil SamplerSieves (128, 64, 32, 16, 8, 4, 2, 1, 0.85, 0.5, Pan): One set is minimal, two will

help in achieving a quicker, more complete drying. Aself-fabricated, 128 mm frame may be necessary as sieves thatsize are difficult to acquire. One additional sieve of thelargest mesh used to employ as extension walls for smallersieves retaining excessively large sample fractions.

Buckets (5 gal.) -- one sample, for collecting and transportingsamples.

Buckets (2.5 gal.) - Two, for collecting and holding clean,surface water for use in the graduated cylinders.

Large (dish)pans -- Two, for initial sample sorting.Graduated Cylinders One a 2 1, Two each 100O.ml, 500 ml, 100

ml.Hamer & Heavy Cloth To break (and control the scatter of

pieces) rocks that are too large to fit in graduatedcylinder openings so that they can be measured.

Rule -- metric, for measuring the longest axis of each sample’sthree largest particles.

Imhoff Cones -- Five.Imhoff Cone Holder -- one.Plastic Cups -- Two; to assist in using sample water in washing

particles through sieves.Turkey basters & squirt bottles -- Two each; to help "zero" water

levels in graduated cylinders, and to assist in washingparticles through sieves.

Large tray (cafeteria type or cookie sheet, with raised edges)two; to capture dropage while hand shaking or transferringparticles from sieves to graduated cylinders.

10 minute timers (suggest digital with sound alarm) - one; forstandardizing settling time for fines in Imhoff cones.

Plastic Bags (1 gallon size) -- for decanting excess water fromfiner sample portions.

Camera - If desired; (a 4 ft x 4 ft sheet of plywood makes aconvenient display surface for placing a sample"s fractionson for photographic purposes).

Funnels, scoops -- various, to assist in transferring material from sieveto cylinder.

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Recommended Data Sheet

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IDEAS ON SHOVEL SAMPLING:

Approximate quotes from Young et al. (1991) and Grost et al.(1991).

"The shovel blade (20 cm wide, 24 cm long) was worked into thestreambed to a target depth of 20 cm, levered until parallel tothe water surface, and gently lifted from the stream. The samplewas allowed to drain for 2-3 seconds before it was placed into acontainer."

I would add that the shovel should be inserted with the bladeupstream of the sample to be excavated. This would assure thatwhat current is present will minimally affect the sediments inthe sample.

I believe that it is likely that the relationship between thelargest particle size collected vs. size of sampler necessaryfound for McNiel Samplers will be similar with shovels; i.e.,when sampling in substrates with particle sizes commonly largerthan 1/3 the blade width, the shovel will be too small (willproduce a biased sample).

SUBSTANTIVE CHANGES SINCE THE OCT 93 VERSION:

95104 -- Change the axis measured for the three largestparticles from their longest to intermediate axis -- that whichcontrols which sieve it would be able to pass. This makes thismeasurement consistent with the measurements of other particles.That is, theoretically, particles are passed through a sieve ifits narrowest cross section will enable it, not its longestcross section.

Lisle comments:

1. Added sentence re. the importance of considering geologywhen selecting a measurement tool *

2. Added second criteria for assessing adequacy of samplersize: i.e., that the largest particle should comprise < 5%of total sample.

3. eliminated the "0.85" from the quote previously attributedto Lisle and Eads, as he does not ascribe a singledefinition of fines.

4. Added figure and discussion from Tappel and Bjornn.2