NOAA Technical Memorandum GLERL-140

ABUNDANCE AND DISTRIBUTION OF BENTHIC 

MACROINVERTEBRATE POPULATIONS IN LAKE HURON 

IN 1972 AND 2000-2003

Thomas F. Nalepa1, David L. Fanslow1, Steven A. Pothoven1, 

Andrew J. Foley III2, Gregory A. Lang1, Samuel C. Mozley3, 

and Michael W. Winnell4

1

NOAA, Great Lakes Environmental Research Laboratory, Ann Arbor, MI 48105

2

Cooperative Institute for Limnology and Ecosystems Research, 

 Univ. of Michigan, Ann Arbor, MI 48104

3

Department of Zoology, North Carolina State University, Raleigh, NC 27695

4

Freshwater Biological Services, Inc., Petoskey, MI 49770

March 2007

UNITED STATES

DEPARTMENT OF COMMERCE

Carlos M. Gutierrez

Secretary

NATIONAL OCEANIC AND

ATMOSPHERIC ADMINISTRATION

Conrad C. Lautenbacher, Jr.

Administrator
2

NOTICE

Mention of a commercial company or product does not constitute an endorsement 

by the NOAA. Use of information from this publication concerning proprietary 

products or the tests of such products for publicity or advertising purposes is not 

authorized. This is GLERL Contribution No. 1420.

This publication is available as a PDF file and can be downloaded from GLERL’s 

web site: www.glerl.noaa.gov. Hard copies can be requested from GLERL, 

Information Services, 2205 Commonwealth Blvd., Ann Arbor, MI 48105.

pubs.glerl@noaa.gov.
3

TABLE OF CONTENTS

1. INTRODUCTION ..................................................................................................................5

2. METHODS ...............................................................................................................................5

Station Locations, Field Procedures.........................................................................................5

Laboratory Procedures..............................................................................................................6

3. RESULTS AND DISCUSSION................................................................................................7

4. REFERENCES .........................................................................................................................7

LIST OF TABLES

Table 1. Location and depth of stations sampled in August 2000 and July/August, 2003 

in the main basin of Lake Huron. Stations are arranged in alpha-numeric order. Stations 

with an “MZ” designation were first sampled in September 1972 by the Great Lakes 

Research Division, University of Michigan. *Denotes stations sampled in 2003 but 

not in 2000; #Denotes stations sampled in 2000 but not in 2003............................................................... 9

Table 2. Location and depth of stations sampled in September 1972 by the Great 

Lakes Research Division, University of Michigan that were not re-sampled in 2000 or 2003 ...............11

Table 3. Location and depth of stations sampled in August 2002 in Georgian Bay and 

North Channel. Stations arranged in alpha-numeric order. Stations with a “GB” designation 

were located in Georgian Bay and stations with a “NC” designation were located in North Channel ... 12

Table 4. List of taxa collected in each of the yearly surveys. The four-letter code identifies the 

corresponding taxa in the excel files given in Appendices 1-4................................................................ 13

Table 5. Mean (± SE) density (no. m-2) of the major taxa at three depth intervals in 1972, 

2000, and 2003. The exact same stations were sampled each year. Differences between years 

for each taxon and depth interval were tested using ANOVA on ln +1 transformed values. 

If years were significantly different (P < 0.05), then a Tukey LSD was performed. Results 

of the Tukey LSD are represented by subscript letters. Values with the same letter were not 

significantly different (P > 0.05). n = 5, 12, and 8 for the 18-30 m, 31-50 m, and 51-90 m 

intervals, respectively .............................................................................................................................. 17

Table 6. Mean (± SE) density (no. m-2) of the major macroinvertebrate taxa at four 

depth intervals in Lake Huron in 2000 and 2003. Standard errors based on station means. 

n = 10, 19, 28, and 8 for the 18-30 m, 31-50 m, 51-90 m, and > 90 m depth intervals in 2000, 

respectively, and n= 17, 27, 33, and 8 for the same intervals in 2003.................................................... 18
4

LIST OF FIGURES

Figure 1. Location of sampling sites for surveys in 2000, 2002, and 2003. Not all sites 

were sampled each year (see text for details). Some sites were located so close that 

a similar mark was shared. Those sites were HU429 and HU429P, and MZ93 and MZ94.................... 20

Figure 2. Locations of sampling sites in the 1972 survey that were not re-sampled in 2000 

or 2003. Sites that were re-sampled are given in Figure 1 and have the “MZ” designation .................. 21

Figure 3a. Density (no.m-2 x103) of Diporeia spp. found in the main basin of Lake Huron 

in 2000. Small crosses denote locations of sampling sites ...................................................................... 22

Figure 3b. Density (no.m-2 x103) of Diporeia spp. found in the main basin of Lake Huron in 

2003. Small crosses denote locations of sampling sites .......................................................................... 23

Figure 4a. Density (no.m-2 x103) of Oligochaeta found in the main basin of Lake Huron in 

2000. Small crosses denote locations of sampling sites .......................................................................... 24

Figure 4b. Density (no.m-2 x103) of Oligochaeta found in the main basin of Lake Huron in 

2003. Small crosses denote locations of sampling sites .......................................................................... 25

Figure 5a. Density (no.m-2 x103) of Chironomidae found in the main basin of Lake Huron in 

2000. Small crosses denote locations of sampling sites .......................................................................... 26

Figure 5b. Density (no.m-2 x103) of Diporeia spp. found in the main basin of Lake Huron in 

2003. Small crosses denote locations of sampling sites .......................................................................... 27

Figure 6a. Density (no.m-2 x103) of Sphaeriidae found in the main basin of Lake Huron in 

2000. Small crosses denote locations of sampling sites .......................................................................... 28

Figure 6b. Density (no.m-2 x103) of Sphaeriidae found in the main basin of Lake Huron in 

2003. Small crosses denote locations of sampling sites .......................................................................... 29

Figure 7a. Density (no.m-2 x103) of Dreissena bugensis (quagga mussel) found in the main 

basin of Lake Huron in 2000. Small crosses denote locations of sampling sites ................................... 30

Figure 7b. Density (no.m-2 x103) of Dreissena bugensis (quagga mussel) found in the main 

basin of Lake Huron in 2003. Small crosses denote locations of sampling sites .................................... 31

Figure 8a. Density (no.m-2 x103) of Dreissena polymorpha (zebra mussel) found in the main 

basin of Lake Huron in 2000. Small crosses denote locations of sampling sites .................................... 32

Figure 8b. Density (no.m-2 x103) of Dreissena polymorpha (zebra mussel) found in the main 

basin of Lake Huron in 2003. Small crosses denote locations of sampling sites .................................... 33
5

Abundance and Distribution of Benthic Macroinvertebrate

Populations in Lake Huron in 1972 and 2000-2003

Thomas F. Nalepa, David L. Fanslow, Steve A. Pothoven, Andrew J. Foley III, 

Gregory A. Lang, Samuel C. Mozley*, and Michael W. Winnell*

1. INTRODUCTION

This technical report gives results of benthic macroinvertebrate surveys conducted in Lake Huron 

between 2000 and 2003, and in 1972. Objectives of the former surveys were to document the status of 

benthic communities, and to assess changes over time. Over the past 20-30 years, the benthic community 

of Lake Huron has been the least studied of all the Great Lakes. While a number of benthic surveys were 

conducted in Lake Huron in the early 1970s (Schelske and Roth 1972; Shrivastava 1974; Loveridge and 

Cook 1976; Great Lakes Research Division-University of Michigan, unpublished data), no wide-scale 

surveys have been conducted in the lake since this time period. With broad changes now occurring in 

many of the other Great Lakes because of phosphorus abatement and the introduction of invasive species, 

an assessment of the benthic community in Lake Huron is both timely and needed. Of particular interest 

is the status of the benthic amphipod Diporeia spp. This ecologically-important organism has declined 

dramatically in Lakes Erie, Michigan, and Ontario (Dermott and Kerec 1997, Nalepa et al. 1998, Lozano 

et al 2001, Nalepa et al 2006) since the introduction and spread of Dreissena polymorpha (zebra mussel) 

and Dreissena bugensis (quagga mussel), and information is needed to determine if similar declines have 

occurred in Lake Huron.

While the 2000-2003 surveys provide recent data on benthic macroinvertebrate populations, the 1972 

survey provides a baseline to which the 2000-2003 data might be compared. This earlier survey was 

conducted by the Great Lakes Research Division (GLRD), University of Michigan, but the data have 

never been published and therefore have not been readily available. 

This report provides details of sampling design, station locations, sampling methods, and laboratory 

procedures of each survey. It also gives the raw data, that is, the number of each taxon found in each 

sample taken. All data are presented with little attempt at analysis or interpretation. Detailed analysis and 

discussion of trends will be provided in other publications. 

2. METHODS 

Station Locations, Field Procedures

Benthic macroinvertebrate surveys were conducted in the main basin of Lake Huron in 2000 and 2003, 

and in Georgian Bay and North Channel in 2002. In the main basin, which can be defined as the lake area 

excluding Saginaw Bay, Georgian Bay, and North Channel, samples were collected at 65 sites in August, 

2000, and at 85 sites in late July/August 2003 (Table 1 and Figure 1). In the latter year, sampled sites 

included all but two sites sampled in 2000, plus an additional 22 sites, some of which were sampled as 

*Note: The 1972 data was collected by the last two authors while at the Great Lakes Research Division, 

University of Michigan. 
6

part of a study to assess benthic prey available to lake whitefish (Pothoven and Nalepa 2006). Among the 

65 sites sampled in both 2000 and 2003, 25 sites were the same sites as sampled in 1972 by GLRD (Table 

1). A total of 50 sites were sampled in the main basin in 1972, thus 25 sites sampled in 1972 were not resampled in 2000 or 2003 (Table 2, Figure 2). 

Samples were collected at 17 sites in Georgian Bay and at 13 sites in North Channel in August 2002 

(Table 3, Figure 1). These sites were a subset of sites sampled as part of the long-term monitoring 

program of water quality parameters by Environment Canada.

In each of the surveys in 2000-2003, triplicate samples were taken at each site with a Ponar grab (area = 

0.047 m2). Each replicate was washed into an elutriation device (funnel-shaped hopper) fitted with a nitex 

sleeve having 0.5-mm openings. Grab contents were placed into the elutriation device, gently stirred, and 

then washed through the sleeve into a collection jar. Retained material was immediately preserved in 5% 

buffered formalin containing rose bengal stain. 

Sampling procedures in 1972 (month of collection: September) were the same as in 2000-2003. Samples 

were taken in triplicate with a Ponar grab, and then washed into an elutriation device similar to the 

one used in 2000-2003. The device was fitted with a cylindrical wire screen having 0.5 mm openings. 

Retained material was preserved in 5% buffered formalin. 

Laboratory Procedures

Retained material was placed into a white enamel pan and organisms were picked, counted, and sorted 

into major taxonomic groups (Amphipoda, Oligochaeta, Chironomidae, Dreissena, Sphaeriidae, and 

other) under a low-power magnifier lamp (1.5 x). All organisms collected in the main basin in 2000 and 

in Georgian Bay/North Channel in 2002 were identified to the lowest practical taxonomic level. For 

oligochaetes, between 75 and 100 individuals in a replicate (proportionately split with a Folsom plankton 

splitter when numbers were higher) were cleared in lacto-nophenol, and mounted on slides prior to 

identification. Only oligochaetes with a prostomium were included in abundance estimates. Chironomid 

head capsules were mounted mentum side up prior to identification. In 2003, organisms were only 

identified to group level (see above). The exception was dreissenids, which were separated into the two 

species (D. polymorpha and D. bugensis). Since oligochaete fragments (without prostomium) can only be 

recognized during the process of species identification and not when counted and sorted, the total number 

of oligochaetes at each site in 2003 was corrected based on the mean proportion of fragments found at 

the same site in 2000 (see Nalepa et al. 1998). For the 20 sites sampled in 2003 and not in 2000, a mean 

proportion for all sites in the same depth interval was used as the oligochaete correction factor. Retained 

material collected in 1972 was sorted under 16x magnification and all organisms were identified to the 

lowest practical taxonomic level. 

Spatial distributions of Diporeia spp., Oligochaeta, Chironomidae, Sphaeriidae, D. bugensis, D. 

polymorpha in the main basin in 2000 and 2003 were plotted using a natural neighbor spatial interpolation 

method and IDL software. Distributions of Diporeia spp., D. bugensis, and D. polymorpha in 2003 not 

only reflect mean densities at the 85 sites sampled, but also mean densities at an additional 23 sites that 

were sampled and provided to us by National Water Research Institute, Canada. These sites were located 

in the northeastern portion of the lake at depths < 35 m. The samples were taken in duplicate with a 

Ponar grab and washed through a screen with 0.5 mm openings. Organisms were counted as described 

previously. 
7

3. RESULTS AND DISCUSSION

Data collected in each of the surveys are given in a series of four excel files: 2000 survey (Appendix 

1), 2002 survey (Appendix 2), 2003 survey (Appendix 3), and 1972 survey (Appendix 4). The data are 

presented as the number of each taxon found in each replicate Ponar grab. To convert to number per m2, 

multiply values by 21.42 for surveys in 2000-2003, and by 21.50 for the 1972 survey. Individual taxa 

within the data files are represented by a four letter code (Table 4). Codes are consistent across surveys, 

but in some cases more specific details are provided for some taxa. For instance, Diporeia collected in 

1972 were divided into categories based on size and sex, and these categories were kept intact in the file. 

Note also that 2003 data are given only for the major taxa (Diporeia, Oligochaeta, Chironomidae, and 

Sphaeriidae) plus D. bugensis and D. polymorpha. 

As mentioned, the purpose of this report is to document site locations, methods, and basic data for 

each individual survey. Since an objective of the surveys in 2000-2003 was to assess changes over 

time, a summary table is provided to show changes at common sites sampled in 1972, 2000, and 2003 

(Table 5). The 25 sites were placed into three depth intervals (18-30 m, 31-50 m, 51-90 m) and mean 

(± SE) densities (no. m-2) of the four benthic major groups (Diporeia, Oligochaeta, Chironomidae, and 

Sphaeriidae) in each interval were determined. Differences between years were tested for each depth 

interval with a one-way ANOVA after ln+1 transformation followed by a Tukey LSD. Densities of the 

major groups were significantly lower (P < 0.05) in 2000 or 2003 compared to 1972, mostly at the two 

deeper depth intervals (Table 5). Declines were most evident for Diporeia, with significantly lower 

densities in all three depth intervals. Overall, mean density of Diporeia at the 25 sites was 4,765 m-2 in 

1972, 1,031 m-2 in 2000, and 466 m-2 in 2003. Densities of oligochaetes and sphaeriids were also clearly 

lower in 2000 compared to 1972, although differences were not as extensive as for Diporeia (Table 5). 

Lakewide distributions of the four major taxa, as well as D. bugensis and D. polymorpha, in 2000 and 

2003 are given in Figures 3-8. In addition, mean densities at four depth intervals (18-30 m, 31-50 m, 

51-90 m, and > 90 m) are given in Table 6. Whereas lower densities were apparent in 2003 compared to 

2000 for each taxon, densities of the two dreissenid species were stable or increased. The mean lakewide 

density of D. bugensis increased from < 1 m-2 in 2000 to 553 m-2 in 2003, while the lakewide density of 

D. polymorpha was 61 m-2 in 2000 and 68 m-2 in 2003. 

Based on trends in Lakes Ontario and Michigan (Mills et al. 1999, Nalepa unpublished data), the D. 

bugensis population in Lake Huron will continue to increase, while the D. polymorpha population will 

likely decline. With a higher assimilation rate and a lower metabolic rate, D. bugensis can outcompete D. 

polymorpha for available food resources (Stoeckmann 2003). These physiological attributes also allow 

it to colonize deepwater habitats unsuitable for D. polymorpha. Since there is a strong negative link 

between dreissenids and Diporeia (Nalepa et al. 2006), the expected, continued expansion of D. bugensis

in deep habitats of Lake Huron will most likely lead to further declines in Diporeia and perhaps other 

major benthic taxa. 

4. REFERENCES

Dermott, R. and D. Kerec. 1997. Changes to the deepwater benthos of eastern Lake Erie since the 

invasion of Dreissena: 1979-1993. Can. J. Fish. Aquat. Sci. 54: 922-930.

Loveridge, C.C., and D.G. Cook. 1976. A preliminary report on the benthic invertebrates of Georgian 

Bay and North Channel. Can. Dept. Environ. Fish. Mar. Serv., Tech. Rep. 610, 46 pp. 
8

Lozano, S.J., J.V. Scharold, and T.F. Nalepa. 2001. Recent declines in benthic macroinvertebrate 

densities in Lake Ontario. Can. J. Fish. Aquat. Sci. 58: 518-529. 

Mills, E.L., J.R. Chrisman, B. Balwin, R.W. Owens, R. O’Gorman, T. Howell, E.F. Roseman, and M.K. 

Raths. 1999. Changes in the dreissenid community in the lower Great Lakes with emphasis on southern 

Lake Ontario. J. Great Lakes Res. 25: 187-197. 

Nalepa, T.F., D.J. Hartson, D.L. Fanslow, G.A. Lang, and S.J. Lozano. 1998. Declines in benthic 

macroinvertebrate populations in southern Lake Michigan, 1980-1993. Can. J. Fish. Aquat. Sci. 55: 2402-

2413.

Nalepa, T.F., D.L. Fanslow, A.J. Foley, III, G.A. Lang, B.J. Eadie, and M.A. Quigley. 2006. Continued 

disappearance of the benthic amphipod Diporeia spp. in Lake Michigan: Is there evidence for food 

limitation? Can. J. Fish. Aquat. Sci. 63:872-890.

Pothoven, S.A. and T.F. Nalepa. 2006. Feeding ecology of lake whitefish in Lake Huron. J. Great Lakes 

Res. 32: 489-501.

Schelske, C.L., and J.C. Roth. 1973. Limnological survey of Lakes Michigan, Superior, Huron, and Erie. 

Great Lakes Research Division Publ. No. 17, University of Michigan, Ann Arbor, MI., 108 pp. 

Shrivistava, H. 1974. Macrobenthos of Lake Huron. Fish. Res. Bd. Canada, Tech. Rep. 449, 45 pp.

Stoeckmann, A. 2003. Physiological energetics of Lake Erie dreissenid mussels: a basis for the 

displacement of Dreissena polymorpha by Dreissena bugensis. Can. J. Fish. Aquat. Sci. 60: 126-134. 
9

*Denotes stations sampled in 2003 but 

not in 2000.

#

Denotes stations sampled in 2000 but 

not in 2003. 

Table 1. Location and depth of stations sampled in August 2000 and July/August, 2003 in the main basin 

of Lake Huron. Stations are arranged in alpha-numeric order. Stations with an “MZ” designation were 

first sampled in September, 1972 by the Great Lakes Research Division, University of Michigan. 

Station Depth (m) Latitude Longitude

AL20* 20.0 44 57.140 83 16.250

AL30* 30.0 44 56.070 83 14.810

AL45* 45.0 44 55.080 83 11.460

AL60* 60.0 44 51.740 83 06.780

AL80* 80.0 44 49.120 83 01.910

AP1* 23.0 45 25.000 83 42.730

FI2 30.0 45 29.987 81 56.495

FI3 46.0 45 29.975 82 02.776

FI4 61.0 45 29.999 82 16.687

FI5 82.0 45 30.008 82 20.383

HB1* 20.0 45 36.830 84 10.190

HB3* 45.0 45 38.156 84 07.764

HB4* 58.0 45 39.600 84 05.300

HB5* 80.0 45 43.373 83 58.820

HU6 50.9 43 27.970 82 00.020

HU9 58.9 43 38.020 82 13.008

HU12 90.0 43 53.393 82 03.371

HU15 66.0 43 59.991 82 21.023

HU27 57.0 44 11.919 82 30.169

HU32 80.0 44 27.205 82 20.471

HU37 71.8 44 45.658 82 46.974

HU38 133.0 44 44.393 82 03.583

HU45 91.0 45 08.203 82 59.059

HU48 112.0 45 16.673 82 27.188

HU53 91.0 45 27.010 82 54.885

HU54 139.4 45 30.990 83 24.952

HU61 116.0 45 44.989 83 54.980

HU93 87.0 44 05.988 82 07.055

HU95 66.0 44 19.994 82 49.954

HU97 45.0 44 54.953 83 09.973

HU325 58.0 45 48.996 84 23.258

HU329 37.0 45 54.760 84 18.126

HU429P# 19.0 45 49.311 84 26.219

HU429 33.4 45 49.447 84 26.208

MZ12 21.0 43 16.181 82 25.705

MZ13 30.5 43 16.170 82 20.439

MZ14 28.8 43 16.188 82 12.044

MZ22 18.5 43 30.303 82 30.155

MZ23 33.0 43 30.419 82 27.265

MZ24 43.0 43 30.601 82 23.268

MZ25 52.0 43 31.180 82 12.250
10

Table 1. Continued.

*Denotes stations sampled in 2003 but 

not in 2000.

#

Denotes stations sampled in 2000 but 

not in 2003. 

Station Depth (m) Latitude Longitude

MZ34 45.0 43 52.617 82 31.737

MZ43 29.5 44 04.009 82 44.775

MZ44 39.0 44 05.705 82 43.063

MZ45 58.0 44 14.505 82 32.993

MZ72 24.0 44 24.279 83 12.484

MZ73 31.8 44 25.397 83 10.515

MZ74 42.0 44 26.304 83 08.802

MZ75 67.0 44 30.924 83 00.174

MZ76 79.0 44 43.487 82 35.500

MZ87 54.7 45 05.854 83 03.497

MZ88 47.0 45 05.341 83 04.643

MZ89 32.0 45 04.771 83 05.781

MZ93 32.0 45 26.469 83 44.591

MZ94 40.0 45 26.304 83 44.304

MZ95 64.0 45 28.688 83 42 208

MZ96 81.0 45 40.641 83 28.575

MZ123 54.0 45 53.661 84 09.611

MZ125 81.0 45 50.712 84 11.575

PT2# 30.0 45 00.049 81 32.991

PT3 45.0 45 00.057 81 35.192

PT5 80.0 44 59.998 81 40.479

PT6 136.0 45 00.023 81 42.495

SB23 28.0 44 13.306 83 15.761

SO2 31.0 44 34.992 81 23.478

SO3 40.0 44 35.036 81 29.993

SO4 57.0 44 35.002 81 31.978

SO5 80.7 44 35.007 81 34.983

SR3* 32.0 45 19.203 83 25.323

SR4* 45.0 45 19.203 83 22.707

SR5 55.4 45 19.203 83 20.165

SR6* 77.0 45 19.203 83 14.503

SR10 56.0 44 49.482 83 06.555

TA20* 20.0 44 09.154 83 20.739

TA45* 45.0 44 18.107 83 11.055

TN1 20.8 43 16.343 82 00.361

TN2 51.0 43 41.800 82 25.000

TN3 65.5 43 41.782 81 55.995

TN4 47.5 44 13.344 81 50.480

TN5 170.0 45 12.447 82 42.492

TN6* 31.0 43 30.002 81 53.489

TN7* 21.0 43 30.037 81 50.558

TN8* 44.0 43 41.800 81 53.734

TN9* 32.0 43 41.800 81 52.421

TN10* 22.0 43 41.800 81 50.366

TN11* 30.0 44 13.406 81 39.987

TN12* 20.0 44 13.458 81 39.121
11

Table 2. Stations sampled in September, 1972 by the Great Lakes Research Division, University of 

Michigan that were not re-sampled in 2000 or 2003.

Station Depth (m) Latitude Longitude

MZ11 10.7 43 16.20 82 29.40

MZ21 11.9 43 30.20 82 32.30

MZ31 12.8 43 51.00 82 37.10

MZ32 21.0 43 51.40 82 35.60

MZ33 36.6 43 52.10 82 33.50

MZ42 19.8 44 03.60 82 45.40

MZ51 11.9 44 02.20 83 09.40

MZ52 15.2 44 04.00 83 11.80

MZ53 21.0 44 06.00 83 14.40

MZ54 22.0 44 08.60 83 17.70

MZ55 22.6 44 10.90 83 21.10

MZ56 20.1 44 13.10 83 24.10

MZ57 11.9 44 14.70 83 26.30

MZ61 11.6 44 00.80 83 31.60

MZ62 18.3 44 07.00 83 30.20

MZ63 20.1 44 10.60 83 27.40

MZ71 10.7 44 21.80 83 16.70

MZ91 14.9 45 25.10 83 46.30

MZ92 22.9 45 25.60 83 45.70

MZ122 26.5 45 54.00 84 09.40

MZ124 62.8 45 52.90 84 10.30

MZ126 59.5 45 47.60 84 13.60

MZ127 42.4 45 45.70 84 14.80

MZ128 25.9 45 43.40 84 16.40

MZ129 16.8 45 41.10 84 17.80
12

Table 3. Location and depth of stations sampled in August 2002 in Georgian Bay and North Channel. 

Stations arranged in alpha-numeric order. Stations with a “GB”designation were located in Georgian Bay 

and stations with a “NC” designation were located in North Channel.

Station Depth (m) Latitude Longitude

GB1 89.0 44 43.05 80 51.40

GB3 32.0 44 43.50 80 37.00

GB4 57.0 44 38.75 80 10.00

GB5 57.6 44 47.80 80 14.60

GB6 86.0 44 44.20 80 26.10

GB8 51.0 44 57.16 80 08.93

GB9 32.0 44 52.30 79 58.08

GB11 61.0 44 55.25 80 36.35

GB12 87.0 44 55.20 80 52.50

GB17 77.5 45 14.70 80 52.50

GB24 39.0 45 44.73 80 50.33

GB26 26.0 45 50.00 80 54.00

GB29 42.0 45 35.00 81 05.00

GB35 33.4 45 31.65 81 40.17

GB36 52.0 45 42.50 81 37.20

GB39 28.0 45 52.40 81 15.50

GB42 26.0 45 54.77 81 35.70

NC68 16.7 46 02.50 83 51.20

NC70 21.5 46 08.20 83 40.30

NC71 35.0 46 14.00 83 44.80

NC73 18.7 46 11.20 83 21.30

NC76 58.0 46 00.00 83 26.00

NC77 77.8 45 58.20 83 11.90

NC79 25.4 46 07.40 82 53.15

NC82 27.2 45 56.20 82 45.50

NC83 30.4 46 00.00 82 33.00

NC84 35.3 46 05.50 82 33.40

NC87 32.0 46 03.67 82 11.83

NC88 33.9 46 03.33 82 00.00

NC89 38.8 45 55.00 82 09.67
13

Table 4. List of taxa collected in each of the yearly surveys. The four-letter code identifies the 

corresponding taxa in the excel files given in Appendices 1-4. 

Survey Year

Taxa Code 1972 2000 2002 2003

Amphipoda

 Pontoporeiidae

 Diporeia spp. (Total) DIPO X X X X

 Young of year (0-3 mm) MM03 X

 Juveniles (3-5 mm) MM35 X

 Adults (5-7 mm) MM57 X

 Adults (> 7 mm) MM07 X

 Females (gravid) GRAV X

 Females (spent) SPEN X

 Males MALE X

 Gammaridae

 Echinogammarus ischnus EGAM X

 Gammarus sp. GAMM X

 Hyalellidae

 Hyallela sp. HYAL X

Isopoda

 Ascellidae

 Caecidotea sp. CAEC X X X

Mysidacea

 Mysidae

 Mysis relicta MYSI X X X

Hirudinea

 Erbodellidae ERBO X

 Glossiphoniidae GLOS X X

 Helobdella stagnalis HSTA X

 Piscicolidae

 Piscicola sp. PISC X

 unknown Hirudinea HIRU X

Oligochaeta

 Sparganophilidae

 Sparganophilus tamesis SPAR X

 Enchytraeidae ENCH X X X

 Lumbriculidae

 Stylodrilus heringianus SHER X X X

 Tubificidae

 Aulodrilus americanus AMME X X

 Aulodrilus limnobius ALIM X X

 Aulodrilus pigueti APIG X

 Aulodrilus pluriseta APLU X X

 Ilyodrilus templetoni ITEM X X X

 Isochaetides freyi IFRE X X

 Limnodrilus cervix LCER X

 Limnodrilus claparedeianus LCLA X X X

 Limnodrilus hoffmeisteri LHOF X X X

 Limnodrilus profundicola LPRO X X X
14

Survey Year

Taxa Code 1972 2000 2002 2003

 Limnodrilus spiralis LSPI X

 Limnodrilus udekemianus LUKE X

 Potamothrix moldaviensis PMOL X X

 Potamothrix vejdovskyi PVEJ X X X

 Rhyacodrilus coccineus RCOC X X X

 Rhyacodrilus montana RMON X

 Spirosperma ferox SFER X X X

 Spirosperma nikolskyi SNIK X X X

 Tasserkidrilus americanus TAME X X

 Tasserkidrilus superiorensis TSUP X X X

 Tubifex tubifex TTUB X X X

 Varichaetadrilus angustipenis VANG X X

 Immatures 

 Without hair setae IMWO X X X

 With hair setae IMWH X X X

 Naididae

 Arcteonais lomondi ALOM X X X

 Chaetogaster sp. CHAE X X

 Nais barbata NBAR X

 Nais behningi NBEH X

 Nais pardalis NPAR X

 Nais simplex NSIM X X

 Piguetiella michiganensis PMIC X X X

 Pristina aequiseta PAEQ X

 Pristina foreli PFOR X

 Pristina osborni POSB X

 Slavina appendiculata SAPP X X X

 Specaria josinae SJOS X X

 Stylaria lacustris SLAC X X X

 Uncinais uncinata UUNI X X X

 Vejdovskyella intermedia VINT X X

Total Oligochaeta TOLI X X X X

Diptera

 Ceratopogonidae

 Probezzia sp. PROB X

 Chironominii 

 Chironomus sp. CHIR X X X

 Chironomus anthracinus-gr. CANT X X

 Chironomus fluviatilis-gr. CFLU X

 Chironomus plumosus CPLU X

 Chironomus salinarius-gr. CSAL X

 Chironomus semireductus-gr. CSEM X

 Cryptochironomus spp. CRYP X X X

 Demicryptochironomus sp. DEMI X X X

 Dicrotendipes sp. DICR X X X

 Dicrotendipes fumidus DFUM X

Table 4. Continued.
15

Survey Year

Taxa Code 1972 2000 2002 2003

 Glyptendipes sp. GLYP X

 Harnischia sp. HARN X X

 Hydrobaenus sp. HYDR X

 Microtendipes sp. MICR X

 Microtendipes pedellus-gr. MPED X

 Omisus sp. OMIS X

 Paracladopelma camptolabis PCAM X

 Paracladopelma cf. nais PNAI

 Paracladopelma nereis PNER X

 Paracladopelma cf. obscura POBS X

 Paracladopelma winnelli PWIN X X

 Paralauterborniella sp. PLAU X

 Paralauterborniella nigrohalteralis PNIG X X

 Paratendipes sp. PTEN X

 Paratendipes albimanus grp. PALB X X

 Phaenopsectra obediens grp. POBE X

 Polypedilum cf. fallax PFAL X X

 Polypedilum cf. ophioidese POPH X

 Polypedilum cf. scalaenum PSCA X X X

 Polypedilum tuberculum PTUB X

 Pseudochironomus sp. PSEU X

 Robackia cf. demijerei RDEM X

 Stempellina sp. STEM X

 Stichochironomus sp. STIC X X X

 Tribelos jucundum TJUC X

 Tanytarsinii

 Cladotanytarsus sp. CTAN X X

 Cladotanytarsus mancus CMAN X X

 Micropsectra sp. MICR X X X

 Tanytarsus sp. TANY X X X

 Tanytarsus cfr. curticornis TCUR X

 Orthocladiinae

 Corynoneura sp. CORY X

 Cricotopus sp. CRIC X

 Heterotrissocladius changi HCHA X X X

 Heterotrissocladius oliveri HOLI X X X

 Orthocladius sp. ORTH X

 Orthoclaius obumbratus OOBU X

 Parakiefferiella sp. PKIE X X

 Psectrocladius sp. PSEC X X

 Tanypodinae

 Ablabesmyia sp. ABAL X

 Ablabesmyia monilis AMON X

 Conchapelopia sp. CONC X

 Procladius sp. PROC X X X

 Tanypus sp. TNYP X

Table 4. Continued.
16

Table 4. Continued.

Survey Year

Taxa Code 1972 2000 2002 2003

 Thienemannimya grp. THIE X

 Diamesinae

 Monodiamesia depictinata MDEP X X

 Monodiamesia tuberculata MTUB X X X

 Potthastia cf. longimanus PLON X

 Protanypus sp. PROT X X X

 Undetermined Chironomidae UNDE X X X

Total Chironomidae TCHI X X X X

Pelecypoda

 Sphaeriidae

 Pisidium sp. PISI X X

 Sphaerium nitidum SNIT X

 Sphaerium sp. SPHA X X

Total Sphaeriidae TSPH X X X X

 Unionidae UNIO X

 Dreisseniidae

 Dreissena polymorpha DPOL X X X

 Dreissena bugensis DBUG X X X

Gastropoda

 Hydrobiidae

 Amnicola sp. AMNI X

 Bythinia tentaculata BYTH X

 Lymnaeidae

 Lymnaea sp. LYMN X X

 Valvatidae 

 Valvata sp. VALV X

 Valvata sincera VSIN X X X

 Valvata tricarinata VTRI X X

 Other Gastropoda OGAS X

Ephemeroptera 

 Ephemeridae

 Hexagenia sp. HEXA X X

Tricoptera

 Leptoceridae

 Oecetis sp. OECE X

 Other Insect OINS X

Turbellaria TURB X X X

Nemertea NEME X X

Other Fauna OFAU X
17

Table 5. Mean (± SE) density (no. m-2) of the major taxa at three depth intervals in 1972, 2000, and 2003. 

The exact same stations were sampled each year. Differences between years for each taxon and depth 

interval were tested using ANOVA on ln +1 transformed values. If years were significantly different (P < 

0.05), then a Tukey LSD was performed. Results of the Tukey LSD are represented by subscript letters. 

Values with the same letter were not significantly different (P > 0.05). n = 5, 12, and 8 for the 18-30 m, 

31-50 m, and 51-90 m intervals, respectively. 

Depth

Taxa/Year 18-30 m 31-50 m 51-90 m

 Diporeia 

 1972 1,896 ± 1,008a 5,892 ± 750a 4,867 ± 551a

 2000 3 ± 2b 592 ± 394b 2,332 ± 365ab

 2003 16 ± 10b 120 ± 88c 1,267 ± 374b

 Oligochaeta

 1972 2,664 ± 919 2,831 ± 414a 1,545 ± 475a

 2000 1,493 ± 259 1,029 ± 292b 723 ± 173ab

 2003 1,308 ± 251 731 ± 135b 378 ± 107b

 Sphaeriidae

 1972 609 ± 402 1,275 ± 210a 462 ± 104a

 2000 187 ± 147 233 ± 44b 243 ± 70ab

 2003 14 ± 11 44 ± 16c 81 ± 25b

 Chironomidae

 1972 419 ± 149 134 ± 28 65 ± 14ab

 2000 121 ± 45 146 ± 55 75 ± 9a

 2003 224 ± 114 62 ± 16 35 ± 10b
18

Table 6. Mean (± SE) density (no. m-2) of the major macroinvertebrate taxa found at four depth intervals in Lake Huron in 2000 and 2003. Standard errors based on station means. n = 10, 19, 28, and 8 for the 18-30 m, 31-50 m, 51-90 m, and > 90 m depth intervals in 2000, respectively, and n= 17, 27, 33, and 8 for the same intervals in 2003. 

Depth Interval

18-30 m 31-50 m 51-90 m > 90 m

Taxa Year 2000 2003 2000 2003 2000 2003 2000 2003Diporeia 244 ± 237 97 ± 92 876 ± 287 248 ± 103 1,918 ± 177 900 ± 130 1,646 ± 254 984 ± 65Oligochaeta 1,648 ± 410 1,783 ± 417 1,196 ± 314 1,460 ± 368 792 ± 87 374 ± 41 661 ± 69 443 ± 74Sphaeriidae 457 ± 196 47 ± 21 237 ± 37 67 ± 13 323 ± 44 106 ± 17 104 ± 35 80 ± 42Chironomidae 883 ± 451 238 ± 55 379 ± 1402 62 ± 14 73 ± 11 27 ± 5 53 ± 12 17 ± 5Dreissena polymorpha 386 ± 342 297 ± 209 6 ± 2 7 ± 4 0 ± 0 18 ± 17 0 ± 0 0 ± 0Dreissena bugensis 3 ± 2 297 ± 180 2 ± 1 1,469 ± 757 0 ± 0 70 ± 44 0 ± 0 1 ± 1
19
20

Figure 1. Location of sampling sites for surveys in 2000, 2002, and 2003. Not all sites were sampled 

each year (see text for details). Some sites were located so close that a similar mark was shared. Those 

sites were HU429 and HU429P, and MZ93 and MZ94. 
21

Figure 2. Locations of sampling sites in the 1972 survey that were not re-sampled in 2000 or 2003. Sites 

that were re-sampled are given in Figure 1 and have the “MZ” designation. 
22

Figure 3a. Density (no.m-2 x103) of Diporeia spp. found in the main basin of Lake Huron in 2000. Small 

crosses denote locations of sampling sites
23

Figure 3b. Density (no.m-2 x103) of Diporeia spp. found in the main basin of Lake Huron in 2003. Small 

crosses denote locations of sampling sites.
24

Figure 4a. Density (no.m-2 x103) of Oligochaeta found in the main basin of Lake Huron in 2000. Small 

crosses denote locations of sampling sites
25

Figure 4b. Density (no.m-2 x103) of Oligochaeta found in the main basin of Lake Huron in 2003. Small 

crosses denote locations of sampling sites.
26

Figure 5a. Density (no.m-2 x103) of Chironomidae found in the main basin of Lake Huron in 2000. 

Small crosses denote locations of sampling sites.
27

Figure 5b. Density (no.m-2 x103) of Chironomidae found in the main basin of Lake Huron in 2003. 

Small crosses denote locations of sampling sites.
28

Figure 6a. Density (no.m-2 x103) of Sphaeriidae found in the main basin of Lake Huron in 2000. Small 

crosses denote locations of sampling sites.
29

Figure 6b. Density (no.m-2 x103) of Sphaeriidae found in the main basin of Lake Huron in 2003. Small 

crosses denote locations of sampling sites.
30

Figure 7a. Density (no.m-2 x103) of Dreissena bugensis (quagga mussel) found in the main basin of Lake 

Huron in 2000. Small crosses denote locations of sampling sites.
31

Figure 7b. Density (no.m-2 x103) of Dreissena bugensis (quagga mussel) found in the main basin of Lake 

Huron in 2003. Small crosses denote locations of sampling sites.
32

Figure 8a. Density (no.m-2 x103) of Dreissena polymorpha (zebra mussel) found in the main basin of 

Lake Huron in 2000. Small crosses denote locations of sampling sites. 
33

Figure 8b. Density (no.m-2 x103) of Dreissena polymorpha (zebra mussel) found in the main basin of 

Lake Huron in 2003. Small crosses denote locations of sampling sites.
34