T ypes of M ethods
T ypes of M ethods
T hree different levels of m acroinvertebrate sam pling procedures are described in this protocol. T hey have unique objectives and require different levels of expertise.
L evel 1 L evel 1 m ethods are the sim plest to use and require the least experience. T hey also provide the least am ount of inform ation about the health of the m acroinvertebrate com m unity. E ducation is the m ain goal for L evel 1. If the m onitoring objective is to inform citizens or students about the various anim als that live in stream s, and only a very basic assessm ent of stream conditions is needed, L evel 1 m ethods w ill be appropriate.
L evel 2 T he L evel 2 protocol is designed to provide a screening level assessm ent of stream conditions. Sites can be classed as heavily disturbed, slightly
d istu rb e d , or non-disturbed. Finer levels of im pairm ent w ill be difficult to detect. If the objective is to screen the condition of a variety of sites for prioritizing m ore in-depth studies, or if the budget or expertise to com plete L evel 3 studies is unavailable, then the L evel 2 protocol w ill be appropriate.
L evel 3 T he L evel 3 protocol provides a sensitive m easure of stream condition using m acroinvertebrate com m unities as the prim ary indicator. Four classes of stream conditions can be determ ined: no
d istu rb a n c e , slight disturbance, significant
d istu rb a n c e , and severe disturbance. A pplied correctly, studies follow ing this protocol can be used for a variety of objectives such as identifying levels of stream disturbance w ithin a w atershed or region, effectiveness m onitoring of restoration projects, trend assessm ents, and evaluating w hether d istu rb a n c e , and severe disturbance. A pplied correctly, studies follow ing this protocol can be used for a variety of objectives such as identifying levels of stream disturbance w ithin a w atershed or region, effectiveness m onitoring of restoration projects, trend assessm ents, and evaluating w hether
designed prim arily for education, don’t require the are m et.
sam e consideration as studies designed to assess stream conditions w ithin or betw een different
M entor C ontacts
stream s. A site w ith easy access and a good
A s w ith any m onitoring project, questions w ill diversity of invertebrates w ill be adequate for m ost com e up that are not answ ered or covered
educational (i.e. L evel 1) projects. sufficiently in this protocol. T herefore, a group of
m entors that are agency experts in m onitoring have For L evel 2 or L evel 3 studies, rem em ber that been identified. T hese m entors m ay be contacted
stream habitats are com plex and change over w ith specific questions about particular m onitoring
distance and tim e. D ifferent com m unities can goals and efforts. Q uestions about
inhabit different portions of the sam e stream , due to m acroinvertebratre m onitoring should be directed to
natural and hum an-caused factors. A lso, the one of the follow ing:
com position and abundance of the m acroinvertebrate species present can change
R ick H afele (503) 229-5983 dram atically betw een seasons due to life-cycle
E -m ail: hafele.rick@deq.state.or.us patterns of the different species. or
C areful site selection and m onitoring tim ing is critical to insure that the data collected are not biased, and that the differences noted betw een sites
M ike M ulvey (503)229-5983 are not due to som e artifact of the m onitoring
E -m ail: m ulvey.m ike@ deq.state.or.us
program design.
Oregon DEQ Laboratory
Selecting Specific Sam ple L ocations
1712 SW 11th Stream s w ith flow ing w ater can generally be Portland, O R 97201
divided into several habitat types: pools, runs, glides, riffles, bends, undercuts, etc. W ithin the
Statew ide D E Q V olunteer M onitoring C oordinator m ajor habitat types other habitat categories can be K aren W illiam s: (503) 229-5983
created. E xam ples w ould be inorganic substrate
E -m ail: w illiam s.karen@ deq.state.or.us like rocks and gravel, or organic substrate like subm erged logs and leaf packs. Since each habitat
N orth C oast type can have a different m acroinvertebrate L arry C aton (503)229-5983
assem blage, deciding w hat habitat(s) to sam ple is
E -m ail: larry.caton@ deq.state.or.us
necessary.
South C oast & W illam ette T w o approaches to habitat selection are com m only
D ennis A des (503) 229-5983 follow ed: m ultiple and single habitat assessm ents.
E -m ail: ades.dennis@ deq.state.or.us
A ssessing m ultiple habitats involves a sam ple design that evaluates tw o or m ore habitat types.
E ach habitat type is sam pled, processed, and L arry M arxer (503) 229-5983
E astern R egional M onitoring C oordinator
evaluated separately. Pools and riffles are the m ost
E -m ail: m arxer.larry@ deq.state.or.us com m on habitat types sam pled in a m ultiple habitat
Selecting Sites
design, but other habitats m ight be included. T he habitats m ost typical of the study stream should be
For an overview of the process used for selecting
chosen.
sites, please review C hapter 3, (Selecting Sites.) T he concepts presented here apply to any of the
R iffles are usually the only habitat sam pled in a the seasonal variability of the stream and to sin g le h a b ita t assessm ent. R iffles tend to contain
determ ine the best tim e of the year to evaluate a the m ost diverse and sensitive invertebrate
specific type of im pact. O nce the seasonality of a assem blage com pared to other habitats (Plafkin et
stream has been adequately characterized, it m ay al. 1989). In m ost cases, a single habitat
be possible to reduce the sam pling to a single assessm ent of riffles w ill be adequate w hen
critical season that best indicates im pacts. sam pling stream s. H ow ever, sam pling only riffles m ay not alw ays be adequate. D efining the
E ffective periods for m acroinvertebrate sam pling in questions in the sam pling plan w ill help determ ine
O regon include:
w hether single or m ultiple habitats should be collected.
W inter: D ecember, January, February Spring: M arch, A pril, M ay, June
N ote: T he analysis procedures presented in this Sum m er: July, A ugust, September chapter apply to “ riffle” habitat only. If m onitors
Fall: O ctober, early N ovember. plan on sam pling other habitat types, they should contact one of the m onitoring m entors to determ ine
D epending on a stream ’s elevation or region in the the best sam pling and assessm ent m ethods.
state, the m onths of M ay/June and O ctober/N ovem ber can be transition m onths
W hen A re Sites Sam pled?
betw een seasons, and invertebrate com m unities Stream habitats w ill have different
m ay be changing faster than at other tim es. M ost m acroinvertebrate com m unities, habitat conditions,
m acroinvertebate studies in O regon are done during and chem ical w ater quality at different tim es of the
sum m er low flow conditions in July, A ugust and year. B ioassessm ent surveys are typically done
Septem ber. W hatever sam pling period is selected, over the course of several years, so it is im portant
sa m p lin g sh o u ld b e a v o id e d d u rin g o r im m ed ia te ly to repeat sam pling at the sam e tim e of year to m ake
a fter h ig h w a ter , because high flow s can year-to-year com parisons possible. Sam pling
significantly effect the ability to collect several tim es per year m ay be desirable to describe
representative sam ples.
E quipm ent
T he follow ing equipm ent, listed separately for L evel 1 and L evel 2-3 assessm ents, w ill be needed to sam ple m acroinvertebrate populations:
T ab le 12-1. L evel 1 assessmen ts.
E q u ip men t:
C osts:
• C ollection n et - K ick screen , or D -fram e kick n et are th e
• $10 - $50
m ost versatile. If th ese are n ot availab le a large fish aq u ariu m n et w ith fin e m esh n ettin g cou ld also b e u sed. Sim p ly p ickin g u p ston es from th e stream b ottom is also an op tion . • Sm all b u ckets
• W aterp roof b oots or w aders • W aterp roof, in su lated, elb ow -len gth gloves (if w orkin g in
p ollu ted or very cold w ater). • Sh allow w h ite p lastic tray (ex. 1 2 ” x 1 6 ” or larger, 1 to 3
in ch es deep ). • 2 to 4 w h ite ice cu b e trays
• T w eezers
• $5 - $10
• Sam p le vials
• M acroin verteb rate field gu ides
• P en cils an d p ap er
• D en atu red eth an ol (8 0 -9 0 % )
• $20 T otal C osts: $ 1 0 0 - $ 2 0 0
T ab le 12-2. L evel 2 an d 3 assessmen ts.
E q u ip men t:
C osts:
• Su b -sam p lin g sortin g tray (C aton T ray)
• T rip od for field sortin g (op tion al)
• ($ 5 0 ) - op tion al
• R an dom n u m b er tab le, or oth er ran dom # gen erator • D -fram e K ick n et, 3 0 cm . w ide D -sh ap ed h oop n et w ith 5 0 0 m icrom eter m esh op en in g
• P lastic sieve b u cket w ith a 5 0 0 m icrom eter m esh b ottom (op tion al)
• P lastic jars w ith tigh t fittin g lids or zip -lock b ags, 0 .5 to 1 .0 liter
• $ 1 0 - op tion al
• D en atu red eth an ol (8 0 -9 0 % ) • Sh allow w h ite p lastic tray (ex. 1 2 ” x 1 6 ” or larger, 1 to 3
in ch es deep ).
• W aterp roof, in su lated, elb ow -len gth gloves (if w orkin g in p ollu ted or very cold w ater).
• L ab elin g tap e an d alcoh ol-resistan t m arkin g p en s (eth an ol dissolves m ost in ks)
• Sm all vegetab le scru b b ru sh • T w eezers
• Sam p le vials
• M acroin verteb rate field gu ides
• P ap er an d p en cils
T otal C osts: $450
Stream Macroinvertebrate Protocol
12 - 4
Water Quality Monitoring Guidebook
Field Sam pling M ethods
L evel 2 and 3 A ssessm ents
B oth L evel 2 & 3 assessm ents follow the sam e field L evel 1 A ssessm ents
sam pling m ethods.
Field procedures for L evel 1 assessm ents can follow a variety of techniques using sim ple, inexpensive equipm ent. T he m ain objective is to
M ethod O verview
collect a representative variety of species from the T he goal of the field sam pling technique is to selected area.
collect an unbiased, representative sam ple of m acroinvertebrates. First, a “ representative” stream reach approxim ately 40 tim es longer than
Procedure the average (m ean) w et surface channel w idth
• If possible, select a shallow area having a should be selected. From w ithin this sam ple reach gravel/cobble bottom w ith a fairly fast current
choose tw o riffles (e.g. if pools w ill be sam pled, (m ake sure the current is not too fast for safe
select tw o pools). T w o 0.18 square m eter (2 square w ading). O ther habitats m ay also be sam pled;
feet) kick sam ples are random ly selected in each for exam ple, w ood and leaf debris, pools, and
riffle or pool. T he four kick sam ples from each stream m argins.
habitat type (riffle and pool) are com bined, • resulting in one com posite riffle sam ple and one
If using a kick screen or D -frame net, place the com posite pool sam ple to process in either the field bottom of the net firm ly against the stream
or the lab.
bottom and disturb the area upstream of the net by picking up pieces of large gravel and cobble and rubbing their surfaces by hand or w ith a
Procedure
sm all vegetable brush upstream of the net. • R andomly select tw o kick-net sites w ithin the
A fter m ost of the cobble-sized pieces have dow nstream riffle or pool. R andom num bers in
been m oved, continue disturbing the stream the table used by D E Q have four digits. T he bottom im m ediately upstream of the net w ith first tw o identify the percent up from the
hands or feet to a depth of several inches. dow nstream end of the riffle or pool, and the R epeat this process at tw o or three locations in second tw o are the percent of stream w idth the sam e habitat type and com bine the contents across the channel. For exam ple, a random
from each net into a single sam ple. num ber of 3225 w ould place the sam ple at
• R emove the net from the stream and w ash its
32 percent up from the dow nstream end and contents into a sm all bucket. C lean and discard
one quarter across the stream w idth. T hese large pieces of gravel, leaves, tw igs, etc. from
percentages are determ ined by visual estim ates. the sam ple.
A fter locating the random sample site, place the • If no net is used, pick up pieces of large gravel
net into the stream w ith the flat part of the hoop or cobble and hold over the bucket w hile
perpendicular to the stream flow and resting on rubbing the surfaces clean. Pieces of w ood and
the bottom . C ollect the m acroinvertebrate leaf packs can also be gently w ashed in the
sam ple by disturbing a 30 by 60 centim eter bucket
area (1 ft x 2 ft) of stream bottom directly • upstream of the net so that the current carries
Pour the material in the bucket into the w hite the m acroinvertebrates and debris into the net. plastic tray, and rem ove all the invertebrates
C arefully rub by hand, or w ith a small scrub brush, all substrate larger than five centim eters • T urn to Sam ple Processing M ethods section
found.
(golf ball size and larger) in front of the net to (below ) for final processing steps.
dislodge any clinging m acroinvertebrates.
Stream Macroinvertebrate Protocol
12 - 5
Water Quality Monitoring Guidebook
A fter rubbin g, place th e substrate outside of th e for sortin g an d subsam plin g in th e lab. C h an ge sam ple plot.
th e alcoh ol in th e sam ple w ith fresh alcoh ol • w ith in on e w eek to en sure adequate
T h orough ly disturb th e rem ain in g substrate to a preservation . Place a label in side th e jar (usin g
depth of five to ten cen tim eters w ith th e h an ds paper an d pen cil), as w ell as an exterior label. or feet. T h is usually takes betw een 30 secon ds For field sortin g, do n ot preserve th e specim en s. an d a m in ute.
K eep th em alive an d follow th e subsortin g •
A fter th e sam ple is collected an d th e n et procedures described in th e n ext section . Field rem oved, th e large substrate is return ed to th e
sortin g is faster sin ce live, m ovin g specim en s sam ple plot.
are easier to see. Field sorted • m acroin vertebrates also ten d to be in better
T h e con ten ts of th e n et are placed in a sieve con dition th an lab sorted specim en s, m akin g
bucket an d th e sam plin g procedure is repeated at
iden tification easier.
th ree m ore plots for th at h abitat type. T h e preferred order for sam plin g is from dow n stream to upstream to m in im ize in fluen ces of
N O T E : T h e disadvan tage to field sortin g is th at it disturban ce to each sam ple plot.
adds on e to th ree h ours to th e field tim e per site. • T h is is especially true for low productivity stream s
A ll four sam ples for th e sam e h abitat type are th at m ay require sortin g m ost, if n ot all, of th e com bin ed in th e sieve bucket. L arge organ ic
sam ple to get th e m in im um n um ber of specim en s m aterial an d rocks are rin sed, carefully in spected
required for an alysis.
for clin gin g m acroin vertebrates, an d rem oved.
A s m uch fin e sedim en t as possible is w ash ed aw ay. L eaf packs from pool sam ples m ay require con siderable rin sin g an d rem oval of debris before preservin g th e com posite sam ple.
• For lab sortin g an d an alysis th e com posite sam ple is placed in a labeled jar or double
Z iplock® bag an d preserved w ith 90% eth an ol
Sam ple site:_________________________________ L ocation:_________________D ate:______________
H abitat sam pled: riffle_____ pool _____ other _____ C ollected by:________________________________
Sam pler type: D -net __________ O ther: __________ # of kicks com posited:_________________________ # of squares sorted:____________________________
Figure 12-1. Field sam ple label inform ation.
3 assessm en ts. For exam ple, L evel 1 assessm en ts do n ot utilize a specific subsortin g m eth od or require a