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005154

ABSTRACT
A QUALITATIVE SURVEY OF THE INVERTEBRATE BENTHOS
OF‘WINTERGREEN LAKE, KALAMAZOO COUNTY, MICHIGAN
by Thomas F. Mitchell

During the summer of 1960, selected bottom areas in
Wintergreen Lake on the W. K. Kellogg Bird Sanctuary,
Hickory Corners, Michigan, were sampled for benthic inverte-
brates.

The morphometry, bottom deposits, aquatic vegetation,
and water chemistries indicated that the lake was eutrophic.
The lake was small (39 acres) and shallow (Figure 1). Bottom
deposits were predominantly marl, organic ooze, and a marl-
organic mixture. Aquatic vegetation was widespread and
abundant, covering perhaps as much as 80 per cent of the
basin. Phenolphthalein alkalinity was usually present in
the shallower areas and the pH was usually above 9. Droppings
from waterfowl which utilized the lake presumably contri-
buted to its eutrophication.

A total of 168 genera were collected and identified.

Of these, 81 were determined to species. The greatest
diversity occurred in the Protozoa with 50 genera (13 identi-
fied to species), the Rotifera with 26 genera (11 identified
to species), and the Tendipedidae with 15 genera (9 identi-
fied to species).

Thomas F. Mitchell
2

The Gastropoda and Pelecypoda were poorly represented.
Heavy predation by waterfowl and possible toxic effects from
waterfowl excreta were credited with reducing the fauna of
snails and clams.

The vast majority of invertebrates were collected
between the shore and the 11 foot depth.

The Protozoa, Rotifera, Oligochaeta, Turbellaria,
Hirudinea, and Tendipedidae were qualitatively most diverse
in stagnant situations. The Ostracoda, Gastrotricha,
Amphipoda, Hydracarina, and Gastropoda were evenly distri-
buted qualitatively.

A substrate composed of sand overlaid with detritus
supported the largest number of species. ‘

A gradient of increasing species diversity to the 11
foot depth was observed. Beyond this depth, there was an
abrupt drop in diversity; only two species of Chaoborus
predominated in the anoxic, severely polluted 21 foot deep
hole in the north end of the lake. The unusual tolerance
of these species is discussed.

A comparison of protected versus unprotected micro-
habitats showed no great difference in total species sup-
ported when protozoans were not considered. The modifying
effects of vegetation and bottom substrate at the unprotected
station seemed to explain this equality. Species composition

at each station was different, however.

A QUALITATIVE SURVEY OF THE INVERTEBRATE BENTHOS
0F WINTERGREEN LAKE, KALAMAZOO COUNTY, MICHIGAN

by

Thomas F. Mitchell

A THESIS

Submitted to
Michigan State University
in partial fulfillment of the requirements
for the degree of

MASTER OF SCIENCE

Department of Zoology

1961

6‘7 x71. 1+
2/23/52

ACKNOWLEDGMENTS

The guidance and encouragement of Dr. T. Wayne Porter
is gratefully acknowledged. His suggestions and criticisms
throughout this work have helped the author to a better
understanding of true research.

Sincere thanks are also due to Dr. L. L. Curry of
Central Michigan university for verification of tendipedid
specimens and to Dr. D. R. Cook of Wayne State University
for verification of hydracarinid specimens. Similar thanks
are extended to Mr. F. Wayne Grimm of Catonsville, Maryland,
for verification of snails.

Tb Dr. M. M. Hensley and Dr. E. S. Beneke for
critically reading the manuscript, appreciation is expressed.

The author is also grateful to Dr. R. C. Ball of the
Department of Fisheries and Wildlife for his helpful advice,
and to Dr. W. G. Morofsky of the Kellogg Gull Lake Biological
Station for use of facilities, and to Mr. R. D. vanDeusen of
the W. K. Kellogg Bird Sanctuary for use of facilities.

For her many favors and kindnesses, the author wishes

to thank Mrs. B. R. Henderson.

11

TABLE OF CONTENTS

Page

Acknowledgments. . . . . . . . . . . . . ii

List of Tables . . . . . . . . . . . . . iv

List of Figures. . . . . . . . . . . . . v
SECTION

I. INTRODUCTION. . . . . . . . . . . 1

II. HISTORY AND DESCRIPTION OF WINTERGREEN LAKE 2

III. PROCEDURE. . . . . . . . . . . . 5

IV. RESULTS . . . . . . . . . . . . 8

Physico-chemical . . . . . . . . 8

Biological . . . . . . . . . . 15

V. DISCUSSION . . . . . . . . . . . 29

Physico-chemical . . . . . . . . 29

Biological . . . . . . . . . . 30

VI. SUMMARY . . . . . . . . . . . . #5

LITERATURE CITED . . . . . . . . . . . . A6

111

LIST OF TABLES

Table Page
I. Description of sampling stations. . . . . 6
II. Physico-chemical data for Wintergreen Lake . 9
III. Invertebrate benthos--Wintergreen Lake--
Summer, 1960 . . . . . . . . . . 18
IV. Qualitative distribution of benthic

invertebrates . . . . . . . . . . 34

iv

LIST OF FIGURES

Figure Page
1. Morphometry of Wintergreen Lake. . . . . 3
2. Carbon dioxide and oxygen variations in

Wintergreen Lake--Summer, 1960 . . . . 10
3. Alkalinity variations in Wintergreen Lake--

Summer, 1960 . . . . . . . . . . 12
4. Temperature differences between protected

(7) and unprotected (8) stations . . . 1A
5. Carbon dioxide and oxygen differences

between protected (7) and unprotected

(8) stations . . . . . . . . . . l6
6. Species diversity vs. depth and bottom type. 42

I. INTRODUCTION

Wintergreen Lake represents an unusual type of habitat.
Its waters contain large amounts of organic matter deposited
by thousands of migratory waterfowl and by the permanent
flocks which reside in the surrounding bird sanctuary.

The prime concern of this investigation was to quali-
tatively survey the benthic invertebrates found in the lake
during the summer of 1960. An effort was also made to dis-
cover distribution patterns of the major groups of inverte-
brates within the lake, and to evaluate the factors which
possibly influenced such patterns.

II. HISTORY AND DESCRIPTION OF WINTERGREEN LAKE

Wintergreen Lake (Figure l) of the W. K. Kellogg Bird
Sanctuary is located at T18, R9W; Section 8 of Kalamazoo
County, Michigan. This places it approximately one mile
southeast of the W. K. Kellogg Biological Station of Michi-
gan State University.

Prior to 1926, when W. K. Kellogg purchased the sur-
rounding area, Wintergreen Lake had been fished extensively
and had been known to yield larger fish on the average than
lakes in the same vicinity. After this date, however,
public fishing was prohibited so that a sanctuary for water-
fowl might become established. Since that time, due to the
large numbers of Canada geese and ducks which utilize the
lake, tremendous amounts of natural fertilizer presumably
have been added to the water.

The lake is consequently considered to be eutrophic
and its morphometry, bottom deposits, and distribution of
vegetation support this idea.

A The lake is a pit lake of glacial origin and covers
about 39 acres. Shallowness is its salient feature, although
a hole reaching to 21 feet exists in the north end (Figure l).

Springs on the north and northeast shores feed the

lake. Drainage is by means of a small outlet on the west

 

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shore, but this seems to be extremely slow, at least during
the summer months.

The major portion of the preceding information has
been obtained from a master's thesis by C. Fetterolf which
dealt with a population study of the fishes in the lake
during the year 1951.

The bottom deposits of the lake are not very diverse.
Shoal areas are sandy, but those on the west are protected
from winds and consequently have a covering of detritus or
pulpy peat. The unprotected east shoal has no such layer.
Deeper areas have a marl bottom and this grades into a fine
organic ooze in the hole at the north end.

The higher aquatic vegetation is very dense. These
plants are distributed rather characteristically. Nuphar
advena Ait, occupies most of the protected west shore; Chara
sp. predominates on the wave-swept east shore, Myriophyllum
sp. occurring sporadically. -Going deeper, one finds a wide
band of Potamogeton pectinatus L. interspersed with some g.
Foliosus Raf. and Najas flexilis (Wild) Rostk. et Schmidt.
A band of Cerotophyllum_gemersum L. exists below this to a

 

depth of 18 feet.

III. PROCEDURE

Sampling was confined to the summer, extending from
June 25, 1960 to August 30, 1960. One sample was taken,
however, on October 7.

On various dates, therefore, samples of lake water and
of selected bottom deposits were taken at nine different
points on the lake, six along a line transect and the
remaining three in separate littoral areas (Figure 1).

Table I contains data concerning the depth, bottom type,
vegetation, and other features present at each station.

Water for chemical analysis was secured with a Kemmerer
sampler and bottom samples were taken with an Ekman dredge.
At the same time, weather conditions were noted.

Physico-chemical data for each station were determined
by means of a Fahrenheit thermometer and a Hach water
analysis kit. Calcium carbonate alkalinity and carbon
dioxide concentration were obtained by titration methods,
pH and oxygen concentration by colorimetric methods. Chemical
tests were run within 20 minutes after the actual collecting.

Immediately after these tests, a finger bowl or two
of bottom material was placed aside, allowed to settle, and
later examined for microscopic organisms. While this
material was settling, the remainder of the bottom deposit!

was run through #10 and #20 screens.
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Hard bodied, non-contractile specimens were preserved
in 70 per cent alcohol and were identified during the sub-
sequent months. On the other hand, most microscopic speci-
mens were identified while still alive, as suggested in
Edmondson (1959)-

With few exceptions, specimens were determined at
least to genus using the following taxonomic keys: (1) B. D.
Burks, 1953, the Mayflies, or Ephemeroptera of Illinois;
(2) E. F. Cook, 1956, The Nearctic Chaoborinae; (3) W. T.
Edmondson (ed.), 1959, Fresh-Water*Biology; (A) R. R. Kudo,
1946, Protozoology; (5) R. W. Pennak, 1953, Fresh-Water
Invertebrates of the United States; (6) S. S. Roback, 1957,
The Immature Tendipedids of the Philadelphia Area; and (7)
H. H. Ross, 1944, The Caddie Flies, or Trichoptera of
Illinois.

IV. RESULTS

Physico-Chemical

 

In general, the data in Table II indicate that Winter-
green Lake was a warm, hard-water lake. Water temperatures
were usually in the 70's; phenolphthalein alkalinity indi-
cated carbonate radicals in solution. Reid (1961) has
stated that hard-water lakes are characterized by pH values
of 8.5 and above. Wintergreen Lake on the whole exhibited
pH values above 9.

Although direct evidence of thermal stratification was
not obtained, this can be inferred from the fact that
chemical stratification did occur (Figures 2 and 3). Further-
more, two previous workers found thermal stratification in
the lake. Fetterolf (1951) found the thermocline to begin
at a depth of approximately 13 feet, and Scheibner (1958)
reported a thermocline in the 21 foot deep hole at the north
end of the lake.

Figure 2 shows that Wintergreen Lake exhibited a
carbon dioxide-oxygen gradient typical of eutrophic lakes.
The large amounts of carbon dioxide and small amounts of
oxygen at the deepest station (#A) were caused by decom-
position of organic sediments and lack of circulation of
the water at that depth. Furthermore, Odum (1959) has

stated that "productively rich lakes generally are subject
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to greater oxygen depletion . . . because the 'rain' of
organic matter from the limnetic and littoral zones into

the profundal is greater . . . For this reason, station
‘#A was probably completely anaerobic and the oxygen recorded
there was probably introduced into the sampling bottle from
the atmosphere during the analysis in the lab. One large
sampling bottle was used for other tests as well as for
oxygen, and this necessitated uncorking the bottle and
agitating the water several times.

Figure 2 also shows that oxygen concentration was
lower in August than in July. This is best interpreted as
caused by increased decomposition of accumulated dead
plankton. Such an increase would also explain the higher
concentration of carbon dioxide at station #A in August.

Figure 3 illustrates alkalinity variations in Winter-
green Lake during the summer of 1960. Although not distinct,
there was a gradient present; monocarbonates (phenolphthalein
alkalinity) decreased with depth whereas bicarbonates
(methyl orange alkalinity) tended to increase with depth.
Moore (1950) has explained such a phenomenon being due to
phytoplankton and higher vegetation (limited to shallower
areas) extracting carbon dioxide from bicarbonates for
photosynthetic activity. Such extraction consequently
produced an increase of monocarbonates, forming marl. The
irregularities in the gradient were probably due to local

concentrations of vegetation.

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Methyl orange alkalinity in general increased in

August because monocarbonates derived from dying and sinking
phytoplankton combined with carbon dioxide to produce in-
creased concentrations of bicarbonates (Moore, 1950). The
exception to this pattern at station 5 was probably due to

a local concentration of Ceratophyllum demersum.

 

Figure 4 illustrates temperature differences between
protected and unprotected stations. The water temperature
of the exposed area tended to follow the change in air
temperature fairly closely, always remaining cooler than
the air. Stirring of the water by wind action produced
changes in temperature of the water paralleling changes in
the air, but the high heat capacity of water always main-
tained its temperature below that of the air.

On the other hand, such a relationship was not seen
for the sheltered area. Water temperatures did not fluctuate
as greatly. Consequently, the water was warmer than the air
at one point and at another point, the water was 14 degrees
cooler than the air. Since water is a much more thermally
stable substance than air, the former's temperature changes
much more slowly than the latter's and thus the water was
warmer than the air on July 20th at station 7. Furthermore,
Welch (1952) has stated that in shallow, unusually protected
areas, even in hot weather, only a thin layer of surface
water may be warmed while the lowermost water may remain
relatively cold. Thus, the 14 degree difference on August
29th.

14

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7:water — —

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80

75

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6/25 6/28 7/20 7/22 8/29

Fig. 4. Temperature differences between protected (7)
and unprotected (8) stations

15

In addition to temperature differences, the protected
and unprotected stations exhibited dissimilarities with
respect to carbon dioxide and oxygen concentration (Figure 5).
The exposed station never had carbon dioxide in solution
and always recorded very high oxygen concentrations. Welch
(1952) found that under conditions of calm, sunny days, the
water surrounding dense vegetation beds may sometimes produce
supersaturations of oxygen of considerable magnitude. The
dense beds of Chara sp. at the exposed station were appar-
ently functioning to this effect.

The sheltered station, on the other hand, eventually
showed presence of carbon dioxide and a corresponding change
in oxygen (Figure 5), Lack of stirring by wind and decom-

position of organic matter seem to have produced such changes.

Biological

The benthos is commonly defined as those organisms
which inhabit or are closely associated with the bottom
substrate of a lake. This definition is, however, too facile
since "the facts of ecological life histories show that the
line of demarcation between benthos and plankton is, to a
great extent, hazy and poorly defined" (Cole, 1955). In
other words, as Welch (1952) has said, ". . . some of the
plankters are facultative benthic inhabitants . . ." In
addition to plankton, it is conceivable that forms normally
on higher vegetation may, through accident or choice, become

incorporated into the benthic community.

20

15

10

 

O x ——————— c—x

 

 

6/25 6/28 7/20 7/22 8/29

Fig. 5. Carbon dioxide and oxygen differences

between protected (7) and unprotected
(8) stations

16

17

This idea of invasion by atypical species is substan-
tiated in the lists of invertebrates compiled in this work
(Table III). For example, Euglena sp., Halteria sp., Synura
sp., and Volvox sp. are considered more planktonic than
benthic. The rotifers, Lecane sp., Macrochaetus sp.,
Polyarthra sp. and Testudinella patina are also thought to
be planktonic. The cladoceran, Daphnia sp., is similarly
regarded.

It must be stressed that these lists are not meant
to be complete since a selected number of microhabitats were
sampled and these primarily during the summer. As Eggleton
(1939) has stated "in typical, eutrophic, temperate lakes
of the second order, the qualitative composition of the
benthic forms will vary considerably with the seasons . . .,"
although Pennak (1953) claimed that "summer and winter
species lists [of protozoans] from the same habitat are
often strikingly similar." Table III indicates that a total
of 168 genera were collected and identified of which 81 were
determined to species. ‘

Based on estimates of numbers, the most abundant

macroscopic organisms observed during the summer were

Limnodrilus udekemianus (Oligochaeta), Qypridopsis vidua

 

(Ostracoda), and Hyalella azteca (Amphipoda).
The collection made at station 9 in October contained
an excessive number of Frontonia sp. (Protozoa) and Simocep-

halus serrulatus (Cladocera) compared to the population

 

sizes of these organisms observed during the summer.

18

TABLE III. Invertebrate benthos-~Wintergreen Lake,
Summer, 1960

_ I j :1

 

Invertebrate benthos Stations

 

l. Protozoa:
Acanthogystis sp.
Acrqpisthium mutabile Perty
Actinobolina sp. .
Actinophryg sp.
Actinosphaerium sp.
Amoeba sp.
Amphileptus claparedei Stein

b
w

Arcella dentata Ehrenberg
Arcella vulgaris Ehrenberg

Balladyna sp.
Centropyxis aculeata (Ehrenberg) Stein

Coleps sp.
Cristigera sp.

 

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Difflugia corona Wallich
Difflugia oblonga Ehrenberg 6,9
Difflugia sp. 2,3,9

DileEtus 3p. 2,7

Epistylis sp. 7
Buglena spp. 3.9
Frontonia sp. 3:6:799

 

Halteria sp. 1.2.3.6.
7.8.9
Histrio Sp. 9

 

TABLE III (continued)

19

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Invertebrate bentho;E Stations
1. Protozoa: (continued)

Lionotus sp. 6
Loxocephalus sp. 9
Loxodes sp. 7.9
Loxophyllum sp. 3
Merotrichia sp. 3
Nassula sp. 2.3.6.7
gnzchodromopsis Flexilis Stokes 6
Ophyroglena sp. 3
Paramecium caudatum Ehrenberg 9
Phacus spp. 3.7.9
Physalophyra sp. 6
Pompholyxophrys sp. 3
Pontigulasia sp. 9
Prorodon sp. 1.7
Pseudomicrothorax sp. 6
Scyphidia sp. 9
Spirostomum sp. 1,3,6,
Stentor coeruleus Ehrenberg I:2:6,7
Stichotrichia sp. 7
Strombidium sp. 3
Strongylidium sp. 3,6,7
Stylonychia sp. 6,9
Synura sp. 9

 

TABLE III (continued)

—‘_

Invertebrate benthos

20

Stations

 

l. Protozoa: (continued)

2.

Systylis sp. ?
Trachelius ovum Ehrenberg

 

Trichodina sp.

 

Trichotaxis sp.

Urocentrum turbo (O. F. Muller)

 

Urozona butschlii Schewiakoff

 

velvox, sp.

Vorticella sp.

 

Unidentified Flagellate

Porifera:

None collected.

Coelenterata:

Hydra sp.

TUrbellaria:

Dalyelliidae

Dugesia tigrina (Girard)
Mesostoma ehrenbergii (Focke)

 

Stenostomum sp.

 

Unidentified Rhabdocoel

Nematode:

Unidentified spp.

Gastrotricha:

Chaetonotusjpopmosus Stokes

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21
TABLE III (continued)

 

Invertebrate benthos Stations

 

6. Gastrotricha: (continued)

 

 

Chaetonotus sp. 1,3
Lepidodermella squamatum (Dujardin) 7
Polymerurus rhomboides (Stokes) 9

 

7. Rotifera:

 

 

 

 

 

 

 

 

 

 

 

 

Cephalodella sp. 2,3
Colurella sp. 5.8.9
Cyrtonia tuba Ehrenberg ‘ 2,6,7,9
Dicranophorus sp. 6
Erignatha sp. 2
Euchlanis sp. . 2.3.6.9
Harringia sp. 2,6
£2233 sp. ‘ 9
Lecane luna Muller 2
Lecane sp. 2.9
Lepadella sp. 3.6
Lindia sp. 3
Macrochaetus sp. 8
Monommata sp. 3
Monostyla closterocerca Schmarda 6
Monostyla guadridentata Ehrenberg 3
Monostyla sp. 2.3.5.9
Mytilina sp. 6.
Philodina sp. 2.3.9

 

 

22
TABLE III (continued)

 

Invertebrate benthos Stations

7. Rotifera: (continued)

 

Platyias patulus (Muller) 2.3.7.9

Polyarthra sp. 9
Resticula sp.

 

Rotaria sp.

0\

Scaridium longicaudum (Muller)
Sinantherina semibullata
Stephanocerus fimbriatus (Goldfuss)

Synchaeta sp.
Testudinella patina

 

Trichocerca porcellus

 

Trichocerca similis

 

moxrooxwoxxocnww

b
w

Trichocerca sp.

 

8. Bryozoa:

Cristatella mucedo Cuvier

 

Lophopodella carteri (Hyatt) 9
9. Tardigrada:

 

None collected.
10. Oligochaeta:
Aeolosoma hemprichi Ehrenberg 6

Aulophorus vague Leidy 9

Chaetogaster langi Bretscher
Chaetogaster limnaei K. von Baer

 

Dero digitata (O. F. Muller)

 

2.3.6
6.9
3,6,9

 

23
TABLE III (continued)

 

 

Invertebrate benthos Sections

 

lO. Oligochaeta: (continued)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Limnodrilus udekemianus Claparede 2,5,8,9
Lumbriculus inconstans (F. Smith) 9
Naidium breviseta (Bourne) 2
3319 communis Piquet 9
Pristina longiseta leidyi Smith 3
Pristina osborni (Walton) 3,6
Pristina schmiederi Chen 9
Stylaria Fossularis Leidy 9
Stllaria lacustris (Linnaeus) 3,6

11. Hirudiaea:
Erpobdella punctata (Leidy) 9
Helobdella stagnalis (Linnaeus) 2,3,7,9
Placobdella parasitica (Say) 9

l2. Cladocera:
Alona guttata Sars 6
Ceriodaphnia quadrangula (O. F. Muller) 3,9
ghydorus sphaericus (O. F. Muller) 3,6
Daphnia sp. 4.5.7
Pleuroxus denticulatus Birge 3

 

Pleuroxus procurvus Birge

 

Simocephalus serrulatus (Koch)

unidentified sp.

 

TABLE III (continued)

 

 

Invertebrate benthos

 

24

Stations

 

13.

l4.

15.

16.

17.

18.

Ostracoda:

Cypria palustera Furtos

 

Cypria sp.

 

Cypridopsis vidua (O. F. Muller)

Hegpetocypris sp.?

Paracandona euplectella (Brady and Norman)?
Physocypria pustulosa Sharpe
Unidentified sp.

Copepoda:

Canthocamptus vagus Coker and Morgan

Eucyclops agilis (Koch)

Macrocyclops albidus (Jurine)

Unidentified calanoid

Unidentified cyclopoid

Isopoda:

None collected.

Decapoda:

None collected.
Amphipoda:

Hyalella azteca
Ephemeroptera:

Ameletus sp.

Caenis sp.

(Saussure)

5
ON

3
h

b
mm

H
mm

[0‘11“ \0 \ONIH w \0
‘0"
woom
OW?

th

 

mans III (continued)

Invertebrate benthos

25

Stations

 

18.

19.

20.

21.

22.

23.

24.

Ephemeroptera: (continued)
Edmundsius sp.
Neocloen sp.
Siphlonurus sp.
Odanata:
Epicordulia sp.

 

Ischnura sp.

mahmmsm
Plecoptera:

None collected.
Hemiptera:

Tenegobia sp.
Neuroptera:

None collected.
Coleoptera:

Berosus sp.

Copelatus sp.

Haliplus sp.
Hydrovatus sp.

Peltodytes sp.
Trichoptera:

Leptocerus americanus (Banks)

 

 

Mystacides sepulchralis (Walker)

1,2,3’6J9

 

TABLE III (continued)

 
  

 

Invertebrate benthos

26

 
 

  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Stations
24. Trichoptera: (continued)
Oecetis sp. l,2,6,8
Orthotrichia sp. 3
Polygentropus sp. 2,3,6,7
Triaenodes tarda Milne 3
25. Lepidoptera:
Acentropus sp. 3
26. Diptera:
A. Culicidae:
£2922 sp. 9
Chaoborus Flavicans (Meigen) 3,4,5,6,7
Chaoborus punctipennis (Say) 4,5
B. Heleidae
Palpomyia sp. 2.3.5.
C.‘ Tendipedidae: 7,8,9
Anatopynia sp. 5.7.9
Calopsectra sp. 3,6,9
Clinotanypus sp. 9
Cryptochironomus digitatus (Malloch) 8,9
glyptotendipes sp. 3,6,8
Harnischia sp. 9
Hydrobaenus (Trichocladius) sp. 6,7,9
Lauterborniella sp. 9

 

 

27
TABLE III (continued)

 

Invertebrate benthos Stations

 

C. Tendipedidae: (continued)

 

 

 

 

 

 

 

 

 

 

 

Pentaneura flavifrons Johannsen 8
Pentaneura monilis (Linnaeus) 2,3,9
Pentaneura sp. 7.8.9
Pglygedilum illinoense (Malloch) 3,7
Procladius riparius Malloch 5,6,7,9
Procladius sp. 7,8
Psectrocladius sp. 9
Pseudochironomus sp. 3,6,8
Tanytarsus sp. 3.6
Tendipgs decorus 3.9
Tendipes nervosus (Staeger) 3,6,8
Tendipes plumosus (L.) 5,6,9
Tendipes staegeri (Lundbeck) 3
Tendipes sp. 1.3.5.3.9

 

27. Hydracarina:

Albia sp. 3
Arrenurus spp. 2.3.5.7

 

Diplodontus (Hydrodroma) despiciens(Muller) 2,3,7

 

 

 

 

szrozetes sp. 2.8.9
Hldryphantes sp . 9
Koenikea sp. 2.6

 

Limnesia sp. 2,7

 

 

TABLE III (continued)

   

 

27. Hydracarina: (continued)
Neumania spp.
2.1212 .1...
Uhionicola sp.
Immature sp.

28. Pelecypoda:
Sphaerium spp.

 

29. Gastropoda:
Gyraulus deflectus (Say)

Gyraulus parvus Say
Lymnaea sp.
Physa sp.

Promenetus exacuous Say

valvata sincera Say

3.5.6.7

‘ 6

M

V. DISCUSSION

ghlgico-Chemical

The physico-chemical data for Wintergreen Lake (Table
11) indicate that it was a eutrophic lake, that is, one
which exhibited warm water temperatures, experienced oxygen
depletion in the hypolimnion, and contained fairly large
amounts of calcium carbonate and bicarbonate. The lake was
shallow (Figure l) and was, therefore, readily warmed during
the summer. Since the hole at the north end of the lake
(Figure l) dropped off abruptly and furthermore was sur-
rounded by a wide band of Ceratophyllum demersum, any sub-
surface currents produced by wind action were ineffective
in circulating the water in the hole (station 4). This,
plus the fact of decomposition of the organic bottom sedi-
ments, accounted for the anaerobic condition found there.
Deposits of glacial drift around the lake probably explain
the hard nature of the lake water.

Of the chemical factors noted in Table II, the most
biologically important is oxygen. Most of the stations had
sufficient amounts of oxygen to support most forms of life.
This was primarily due to the photosynthesis of the dense
vegetation at these stations. 0n the other hand, station

4 was virtually anaerobic for reasons already discussed.

29

30
Station 9 also showed low oxygen concentrations; this was
because (1) there was little vegetation present, (2) the
area was choked with decaying detritus, and (3) the area was
shaded throughout most of the day by a willow tree.

Other biologically important chemical factors not
included in Table II, but which nevertheless were undoubtedly
present in fairly large quantities, were hydrogen sulfide,
ammonia, and other toxic organic breakdown products. The
thousands of waterfowl which utilized the lake apparently
contributed these toxic substances by depositing their
“urine. and feces in the lake. Such toxic substances might
quite possibly have played an important role in the occur-

rence and distribution of many of the invertebrate groups.

Biological

The complete absence of several groups and of certain
typical benthic species may have been due to any of the
following: (1) inadequate sampling, e.g. the Isopoda,
Tardigrada, and Neuroptera are not uncommon in lakes; (2)
physiological limits, e.g. the Porifera are more sensitive
to environmental variations than are other fresh-water
invertebrates (Pennak, 1953). in this case perhaps toxic
organic waste products; (3) habits, e.g. the Plecoptera are
mostly stream-dwellers and the Decapoda are chiefly nocturnal
(all collecting was done during the day); (4) predation, e.g.
the Decapoda are a prime fish food; or (5) the existence of

a narrow concentration zone of the absent forms. Alona

31
guadggggularis, Drgpanothrix sp. and Ilyocgyptus sp. are

typical benthic cladocerans, and yet were never found.

 

Furthermore, Hexagenia limbata, a burrowing mayfly
nymph, was not collected, either by the author during his
research or by R. H. Scheibner who conducted a year-long
quantitative study on the insect bottom fauna of the lake in
1957. The latter's sampling stations were along a different
transect and at different depths for the most part than
those in this study. However, during an excursion around
the lake on July 6, 1961, this species was collected in a
very limited area on the west shore. This area had not been
sampled by Scheibner or the author during their investi-
gations. Hunt (1953) observed that H. limbata preferred a
marl-organic mixture and that ". . . fewer nymphs existed
in thickly vegetated bottom. . ." Such a condition seemed .
to exist in this locality and may account for the presence
of this organism.

Another evidence for the existence of concentration
zones in the lake was the fact that both Scheibner and the
author during their work, had witnessed large emergences of
the mayfly Caenis sp. However, neither worker found this
organism in large numbers in the bottom sediments.

The paucity of species among several insect groups and
in the molluscan groups likewise may have been due to any of
the causes mentioned above. Inadequate sampling undoubtedly

produced only one species of Hemiptera. Scheibner (1958)

32
collected Notonecta sp. and Plea striola (Hemiptera) in 1957.

He also found two beetles, Bidessus sp. and Tropisternus sp.,

 

which were not present in the author's samples.

It is well known that lakes lose much of their insect
population through the emergence of adults usually in the
spring and early summer. Scheibner (1958) collected the
following odanate nymphs primarily in the winter--Basiaeschna

 

janata, Enallagma sp., Libellula sp., Perithemis sp., and
Tetraganeuria sp. He also collected Leptocella sp. and
Phgyganea sp. (Trichoptera). The author did not find the
nymphs of these genera during the summer.

Three facts account for the qualitative paucity of
pelecypods in the lake. Pennak (1953) has stated that,
". . . small lakes, especially seepage lakes, contain few
species" and that "customarily, mussels inhabit substrates
free of rooted vegetation. . . . The Sphaeriidae are less
specific in their occurrence. . . ." Reid (1960) has stated
that ". . . pelecypods are eaten by various fishes and other
animals including muskrats and waterfowl."

Similarly, the snail fauna in Wintergreen Lake was
rather limited. Several factors may have been responsible
for this. Small bodies of water usually have few species
compared to larger bodies of water because there are fewer
microhabitats specific for each particular species (Pennak,
1953). Predation by fish, birds, and the snail leech

Helobdella stagnalis is common (Pennak, 1953). The larger

33
species of snails apparently did not exist in the lake. The

extremely large numbers of fish and waterfowl in the lake
may have "overgrazed" the more easily detected larger snails.
Another factor in reducing the snail fauna may have been the
toxic waste products produced by the droppings of the water-
fowl which utilized the lake. Boubjerg and Ulmer (1960)
found only 11 species in Lake Okoboji, Iowa, compared to 36
species found there by Shimek 25 to 30 years previously.
These workers cited pollution by sewage as the major cause
of this gap.

Table IV illustrates the distribution of each major
group collected and identified. Where gaps exist between
depths, it may be assumed that the group in question was
present at that depth, but not necessarily at the station
shown. Examination of the locations of the sampling stations
in Figure 1 provides an explanation for this situation.
Furthermore, physico-chemical properties of individual
stations may be limiting to certain groups. These gaps can
be attributed to sampling error and/or insufficient examin-
ation of the samples from that depth.

Obviously, the distribution of each group may not be
complete since there were depths which were never sampled.
However, the range as shown for each group may be of some
value in portraying approximate depth limitations.

These limitations, furthermore, cannot be considered

as absolute since "the depth distribution [of various benthic

34

 

 

 

 

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-- -- H H -- m H m m HmvssoononoEoram
-- -- H H H H H H H HHS soooHnosa

H -- H m H H -- H s Hmv soononoo
-- H m m m m m m m Hey cooosnono

H -- H m m H -- m m Amy snoooosHo
-- -- -- H H -- -u H m Amy sosHossHm
-- H w m m H -- -- m HHHvsoossoomHHo
nu uu nu H nu nn nn un H Amv monomam
-- -- mH MH «H m -- m 6H HHmv nsoeHoom
-- -- H m -- -n H H m. HsvsroHnoosoaso
-- -- m m H H H m m HmvsHssHHoosse
uu uu H uu nn H nu nn nu Avaumaouconoo

H H mm on oH H m eH .oonmm Asmvsonooosn
.o .o .o.z .o.: .z .z.m .a.m .m.m .n.m . sesame soeoom
.Hm .mH .HH .m .n. .m .m.w .m _.m. sense
a m w m m m H h m COHpopm

 

IIHH nklnl

.mbpmhnonhm>cH odnpcon no coauzndhumdc 0>HuwuHHQSG .>H mqmgfi

35

g

 

 

 

m m as «w mH Hm wH mH mm HmmHv gases
-- H m m m m m H . m Hoe soonosonso
nu nn H un H H H nu nn AHV mooaaoonm
n- H H H m H u- m m HoHv annsooaoH:
-- m 0H 6H . H m H o HHHmmvosoHoonHocme
-- -- H H H H -- H H HHS osoHoHom

m m H H -- -- -- H H Amy osoHoHHso
-- -- -- H -- -- -- -- -- HHV snoooooHnoH
-- -- m H m m m H -- Hmv snoooosoHse
nn nn nu nn H H nn nu H Amy mnouaooHoo
nn nu nu nn nn nn nn nu H AHV whodesmm
-- -- H m H -u H H H Amy sonocoo
.o .o .o.z .o.: .z .z.m .a.m .m.m .o.m henna soooom
.Hu .mH .HH .m .m .m .m.m .m .m. spasm
H m w m m m H h m GOHumpm

 

HooscHocooV .>H mange

36
groups] found at one time of the year cannot be assumed to be
the distribution typical of that type of lake or even that
individual lake at all other times of the year" as has been
stated by Eggleton (1935).

Table IV indicates that the great majority of the
invertebrate groups penetrated to at least the 11 foot depth,
but usually not to the 16 foot depth. Table I shows that
at 16 feet, the substrate was an organic ooze, vegetation
was sparse, and hydrogen sulfide was present. Table II
shows that this depth also exhibited fairly low concentrations
of dissolved oxygen. This complex of unfavorable conditions
was apparently limiting to most species.

Some species, however, were more tolerant of unfavorable
conditions. A small green flagellate was found at 21 feet
along with two species of Chaoborus (Culicidae). Hall (1953)

 

has stated "chlorophyll-bearing species [of protozoa] are
often saprozoic and some can grow in darkness." Cole (1955)
noted that "Phacotus sp. was the only green flagellate found

regularly in the anoxic hypolimnion. . . . Chaoborus sp.

 

is a typical profundal inhabitant and will be discussed
below.

The cladoceran and copepod at 21 feet were probably
recently dead or dying, having sunk from the upper limnetic
zone.

Clench (in Edmondson, 1959) observed that many pulmon-

ate (lung-bearing) snails can remain submerged in water for

37
indefinite periods of time, exchanging gas through the body
surfaces. This adaptation may have accounted for the
presence of Gyraulus parvus at the 16 foot depth. It was
surprising, however, to find this snail there when carbon
dioxide and oxygen concentration were 8 p.p.m. and 5 p.p.m.,
respectively. Pennak (1953) indicated that pulmonate snails
require rather high concentrations of dissolved oxygen.

Later in August at this depth, Limnodrilus udekemianus,
Physocypria pustulosa, and Neumania sp. occurred there when
carbon dioxide was absent and oxygen was 4.2 p.p.m

The Coleoptera were not found beyond the 5 foot depth.
Most adults in this group must obtain their oxygen from the
surface and must, therefore, remain in relatively shallow
water.

On a more specific level, an examination of Table III
shows that the most widely distributed species in the lake
were the following: Halteria sp., Spirostomum sp., Vbrticella
sp. (Protozoa); Dugesia tigrina (Turbellaria); Simocephalus

 

serrulatus (Cladocera); Cypridopsis vidua, Physocypria
pustulosa (Ostracoda); Macrocyclops albidus (Copepoda);
Hyalella azteca(Amphipoda); Chaoborus flavicans (Culicidae);
Palpomyia sp. (Heleidae); Tendipes sp. (Tendipedidae);
Gyraulus parvus, and Phyga sp. (Oastropoda).

The proportion of species within a major group found
at any one station (microhabitat) may be used in ascertaining
the microhabitat requirements of that group. Presumably,

38
most species within a group are found in that environment
which is most favorable for growth and reproduction of that
group.

Protozoan diversity was greatest at station 9, 6, and
3, in that order(Table IV). Kudo (1946) has said that the
majority of fresh-water protozoans "live in waters in which
active oxidation and decomposition of organic matter are
taking place." The quantities of carbon dioxide and oxygen
at station 9 corroborated this statement. However, no such
corroboration held for stations 6 and 3 (see Table II). The
sediments and immediate overlying water at stations 6 and 3
were probably more stagnant than the data indicate, because
the Kemmerer sampler was lowered to a depth one foot above
the bottom so as not to stir up the sediments. Welch (1952)
has stated "bottom deposits, through.their decomposition
processes, consume oxygen, exhausting it . . . not only
within themselves but also in a thin layer of water lying
immediately above the bottom, thus producing a microstrati-
rication.f ’ '

Although not quite as striking, the rotifers and
oligochaetes seemed to require a microhabitat similar to
that required by the protozoans.

The Turbellaria, Hirudinea, and Coleoptera were quali-
tatively concentrated at station 9. Pennak (1953) has noted
that many rhabdocoels are characteristic of microhabitats

of much decay and low oxygen and that most flatworms are

39
photonegative. Station 9 was low in oxygen and was shaded
during most of the day; hence the flatworm diversity there.
Although planarians require high oxygen concentrations,
Dggesia tigrina was found at Station 9. This Species may
have been obtaining oxygen at the airfwater interface.

Pennak has further noted that leeches prefer warm
protected shallows with much vegetation and debris. Clampitt
gt 91. (1960) reported that leeches showed definite prefer-
ence for sand substrates except Helobdella stagnalis which

 

was widely distributed. The findings of this investigation
coincide closely with these observations (see Tables III
and IV).

Most species of Bryozoa avoid direct sunlight and
'"Lgphopodella carteri is probably the species that is most

 

tolerant of decay and stagnation" (Pennak, 1953). Thus
this species was found at station 9 (see Table III).

In general, copepods are more tolerant of a deficiency
of oxygen than are cladocerans (Pennak, 1953). Four of the
five species of copepods were taken at station 9, whereas
only two of the eight species of cladocerans were taken
there.

Pennak has stated that ostracods "tolerate wide ranges
of ecological factors" and that the nature of the substrate
is not important in their distribution. As seen in Table IV,
this group was fairly evenly distributed. The Gastrotricha,

Amphipoda, and Hydracarina were similarly distributed.

40

The Gastropoda likewise were fairly evenly distributed
and this, Boubjerg and Ulmer (1960) also discovered in Lake
Okoboji, Iowa. waever, these workers never found snails in
or about Chara sp. beds, whereas this worker did (at station
8). Although pulmonate snails are usually not found in
stagnant water (Pennak, 1953). such species were found at
station 9 (which was stagnant). Since this station was quite
shallow (6 inches), these forms were probably obtaining
oxygen from the atmosphere at the surface.

Allee and Schmidt (1951) have noted that "contrary to
a condition frequently found in terrestrial insects, the
aquatic insects are seldom limited to definite plants." An
exception to this is the habitationclf the tips of

Ceratophyllum demersum by Leptocerus americanus (Ross, 1944).

 

 

Considering tendipedid larvae, Procladius riparius and

 

Tendipes plumosus were the only midge larvae which penetrated

 

to the 16 foot depth. The midges in general exhibited a
distribution similar to that of the Protozoa and Rotifera
(see Table IV). This was not surprising since it is well
known that many midge larvae can withstand rather low con-
centrations of dissolved oxygen (Surber, 1958). Curry (1954)
noted that the largest number of species was found in the
littoral zone and was "directly associated with the dense
plant growth of this region." Hence, the concentration of
this group at stations 9, 6, and 3. The following species
of midges were found exclusively at Station 9 (a fairly

41
stagnant area): Clinotanypus sp., Harnischia sp., Lauter-

borniella sp., and Psectrocladius sp.

 

Figure 6 illustrates the influence of depth and bottom
type on species diversity. Eggleton (1939) has stated that,
in general, the benthic fauna increases qualitatively with
depth to an optimum level somewhere within the lower littoral
or upper sublittoral and then decreases with depth to a
minimum in the deepest regions. This relationship was
observed along the transect (stations 1-6) in the lake.

Station 9, however, supported the greatest diversity
of species. This was probably due for the most part to the
nature of the substrate there. Cole (1955) noted that a
detritus-like bottom likewise supported the largest number
of species.

The extreme paucity of species at 21 feet (see Figure
6) was also noted by Scheibner (1958). In addition to
Chaoborus sp., he also found Palpomyia sp., Tendipes sp.,
and Tanytarsus sp. However, these additional forms were
present only during April, May, and December and then only
in very low numbers. Forms quite often found in deeper
waters, e.g. Oligochaeta and Sphaeriidae, were never
collected at station 4. It would seem, therefore, that the
chief limiting factor, rather than absence of oxygen, was
decomposition products, especially hydrogen sulfide.

The occurrence of Chaoborus sp. under such adverse

 

conditions has not been fully explained. It is well known

42

o«cmwnmvnno “HHMZWnZ updmmnnm nmfiudhponnnn “Undmnnm *

nah» aouuon use canon .m> mprao>Ho mcHomam .m .mHm

 

 

CO .0 00.: 00.: 0: OEOm Om.” .mOm *anm Oppom
.HN .wa .HH .0 .m .m .m.w . .N .m. SDQOQ
H m m m m m H a. m .som
Agni? 0
mm
on
I
ma.
O/O
.|..I. monocoam .Hoxm
.Iln monopoam .HoSn.
OOH

 

 

43
that Chaoborus sp. larvae migrate to the surface at night
and might thereby obtain temporary relief. However, Eggleton
(1932) has observed Chaoborus sp. migrating nocturnally (1)
during the winter when the lake was covered with ice and
snow, and (2) during the autumnal overturn when the lake
was completely aerated from surface to bottom. These obser-
vations seem to indicate that the determining factors of
such migrations are not light or oxygen requirement, although
these both may be operable.

Although a sandy, wave-swept shore usually supports
the fewest number of species (Allee andSchmidt, 1951), the
thick Chara sp. beds at station 8 were probably preventing
any molar action by the waves and thus a relatively large
number of species was collected there (Figure 6). Further-
more, the marl mixed with sand probably served to stabilize
the latter and to give the sand some consistency.

Figure 6 shows that the protected station (7) had a
greater number of different species than the unprotected
station (8). This difference in total number of species
supported was due to the larger number of protozoans present
at station 7; most protozoans occupy stagnant situations;
station 7 was stagnant and station 8 was not. The protozoans
excluded, the two stations supported almost the same number
of species.

Station 7 was also qualitatively richer in cladocerans

and water mites whereas station 8 supported a greater

44
diversity of tendipedids and snails. Chara sp. may possibly
have influenced the former groups adversely. Many snails
are known to forage on aquatic plants and the midges
apparently found the more stable substrate of station 8 a

more favorable one in which to burrow.

VI. SUMMARY

1. Wintergreen Lake on the W. K. Kellogg Bird
Sanctuary was found to be eutrophic,rendered so primarily
by the droppings of thousands of waterfowl in and around the
lake. Such natural fertilization presumably contributed
large amounts of nitrates, phosphorus, and other important
trophic substances.

2. A total of 168 genera were collected and identified.
Of these, 81 were determined to species. Qualitative diver-
sity was greatest in the Arthropoda, Protozoa, and Rotifera.

3. The molluscan fauna in the lake was qualitatively
meager.

4. The Protozoa, Rotifera, Oligochaeta, Turbellaria,
and Tendipedidae were best represented in situations low in
oxygen and rich in organic matter.

5. A substrate composed of detritus supported the
greatest number of different species.

6. Chara sp. beds present in an unprotected area
allowed a greater number of species to exist there than

otherwise would have been possible.

45

LITERATURE CITED

Allee, W. C. and K. P. Schmidt. 1951.
Ecological Animal Geography. John Wiley and Sons,

Inc., New York.

Boubjerg, R. V. and C. G. Ulmer. 1960.
An Ecological Catalogue of the Lake Okoboji Gastropods.
Proc. Iowa Acad. Sci. 67:569-577.

Mk8, Be Do 1953.
The Mayflys, or Ephemeroptera, of Illinois. Bull.
Ill. Nat. His. Surv. V61. 26, 216 pp.

Clampitt, P. T. g£,al. 1960.
An Ecological-Reconnaissance of the Bottom Fauna,
Millers Bay, Lake Okoboji. Proc. Iowa Acad. Sci.,

67:553-568.

Cole, G. A. 1955.
An Ecological Study of the Microbenthic Fauna of Two
Minnesota Lakes. Amer. Mid. Nat., 53:213-230.

Cook, E. F. 1956.
The Nearctic Chaoborinae. U. f Minn. Agr. Exp. Sta.
Bull., #218. "' "' ”“77 "-

Curry, L. L. 1954.
An Ecological Study of the Family Tendipedidae of Two
FreshHWater Lakes in Isabella County, Michigan.
Unpub. Ph.D. Thesis, Mich. State Univ.

Edmondson, W. T. (ed.). 1959.
Fresh-Water Biology. John Wiley and Sons, Inc.,
New Ybrk.

Eggleton, F. E. 1932.
~ Limnetic Distribution and Migration of Corethra Larvae
in The Michigan Lakes. Pap. Mich. Acad. §gi., Arts
Egg Lett., 15:361-388.

. 1935.
A‘Camparative Study of the Benthic Fauna of Four
Northern Michigan Lakes. Pap. Mich. Acad. Sci., Arts
and Lett., 20:609-644.

 

 

 

46

47

Eggleton, F. E. 1939
Role of the Bottom Fauna in the Productivity of Lakes.
Amer. Assoc. Adz. Sci,. Publ. #10, 123- 131.

Emerson, R. and L. Green. 1938.
Effect of Hydrogen-Ion Concentration on Chlorella
Photosynthesis. Plant Physio., 13:157-158.

Fetterolf, C. 1952.
A Population Study of the Fishes of Wintergreen Lake,
Kalamazoo County, Michigan with Notes on Movement and
Effect of Netting. Uhpub. M.S. Thesis, Mich. State
UHiV. ' ‘

Hall, R. P. 1953.
Protozoology. Prentice—Hall, New York.

Hunt, B. P. 1953.
The Life History and Economic Importance of a
Burrowing Mayfly He enia limbata in Southern
Michigan Lakes. ’Ins%. FIsE. Res. s611.1#u, Mich.
Dept. Cons.

 

Kudo, R. R. 19A6.
Protozoology. Thomas, Springfield, 111.

Moore, W. G. 1950.
Limnological Studies of Louisiana Lakes: 1. Lake
Providence. Ecology, 31:86-99.

Odm, E. P. 1959.
Fundamentals of Ecology. W. B. Saunders, Philadelphia.

Pennak, R. W. 1953.
Fresh-Water Invertebrates of the United States.
Ronald Press, New YOrk.

Reid, G. K. 1961.
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