AN ECOLOGICAL STUDY OF SOME OF THE CHIRONOMIDAE

INHABITING

A

SERIES OF SALINE LAKES

IN CENTRAL BRITISH COLUMBIA WITH SPECIAL REFERENCE TO

CHIRONOMUS TENTANS FABRICIUS

by
Robert Alexander Cannings
BSc. Hons., University of British Columbia, 1970

A

THESIS SUBMITTED IN PARTIAL FULFILMENT OF

THE REQUIREMENTS FOR THE DEGREE OF
MASTER OF SCIENCE

in theDepartment

of

Zoology
We accept this thesis as conforming to the

required standard

THE UNIVERSITY OF BRITISH COLUMBIA
May, 1973

In presenting this thesis in partial fulfilment of the requirements for

agree that

an advanced degree at the University of British Columbia,
I

the Library shall make i t freely available for reference and study.

I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the Head of my Department or

by his representatives.
It is understood that copying or publication of this thesis for financial gain shall not be allowed without my

written permission.

Department of

The University of British Columbia

Vancouver 8, Canada

Date

i i

ABSTRACT

This thesis is concerned with

astudy of the

Chironomidae occuring in a saline lake series in central British Columbia. It describes the ecological distribution of species, their abundance, phenology and interaction, with particular attention being paid to Chironomus tentans.

Emphasis is placed on the species of Chironomus that coexist in these lakes and a further analysis is made of the chromo-

some inversion frequencies in C. tentans.

Of the thirty-four species represented by identifiable adults in the study, eleven species have not been previously

reported in British Columbia, five are new records for Canada

and seven species are new to science.
The chironomid fauna of the lake series is divided into dominant associations whose existence seems to depend on salinity and productivity levels. Procladius bellus Ablabesmyia peleensis association pre-

vails in the lowest salinities (40 to 80 jumho/cm conductivity) while in conductivities between 400 and 2800 jumho/cm

Glyptotendipes barbipes Einfeldia pagana association dominates. In the most saline lakes (conductivity 4100 to 12000
Calopsectra gracilenta Cryptotendipes ariel association ischaracteristic.

A

Cricotopus albanus

-
-

a
-

jumho/cm)

• a
• -

Analysis of physical and chemical factors influencing the l i f e cycle of C. tentans indicates that conditions associated

with high levels of organic carbon promote large numbers of larvae and greater emergence success. The results suggest that competition between C. tentans and other Chironomus species isreduced through spatial separation due to different preferences forsalinity or related factors.
Furthermore,

temporal separation among these and other abundant species such as G. barbipes and E. pagana occurs as a result of staggered generation times.

The inversion frequency inchromosome 1 of C. tentans is negatively correlatedwith organic carbon levels and positively correlated with dissolved oxygen and the abundance of Glyptotendipes barbipes. Since the inversion frequency is lowest inhabitats where competing species are few and where C. tentans ismost successful, i tissuggested that the inver-

sion governs

a

mechanism reducing competition.

Amajor contributionof this work istherevision ofthe

distribution of many of the chironomid species under considera-
In the past, l i t t l e research has been done on populations of chironomids ina saline lake series. The present this gap inentomological research,

tion.

study, inattempting to

shows that

f i l l

a

species' l i f e history and population structure can vary radically inclosely associated lakes of differing

chemical and biological constitution.

IV

TABLE OF CONTENTS

Page

Title Page

i

Abstract

• i
• i

Table of Contents List of Tables

List of Figures

List of Plates

Acknowledgements

iv

v i

v i i i

x i

x i i

I

INTRODUCTION

1

II

THE LAKE ENVIRONMENTS

A. THE STUDY AREA
44
B. THE PHYSICAL AND CHEMICAL PROPERTIES
OF THE LAKES
8

III

SPECIES DIVERSITY AND THE CHIRONOMID COMPLEX

IN THE LAKE SERIES
17

• 17
• A.

MATERIALS AND METHODS

• 1. Temperature Records
• 17

17 17 19
2.

Biological Sampling Methods

a) Larval Sampling b) Adult Sampling

• 3. Rearing of Specimens
• 23

4.

Preparation and Identification

of Specimens
24

• 24
• 5.
• Analysis of the Data

6. Storage of the Data for Further

• Study
• 24

26
B.

RESULTS

26 30
1. Water Temperatures in the Lake Series 2. Chemical Data

• 3
• The Occurrence of Species in the

• Lakes
• 30

4. 5.

Species Considered in Detail

The Chironomid Complex and the

Lake Series

33
85

a)

The Cricotopus albanus

-

Procladius bellus

-

Ablabesmyia

• peleensis association
• 85

86 b) c)

The Glyptotendipes barbipes

-

Einfeldia pagana association The Calopsectra gracilenta

Cryptotendipes a r i e l

association

-

88

C. DISCUSSION

1. 2.

The Chironomidae andthe Lake Series

91

Chironomus tentans andthe Lake

Series

102

a) b)
Physical and Chemical Influences Biotic Interactions

102 106

IV

CHIRONOMUS TENTANS AND SOME BIOTIC FACTORS AFFECTING CHROMOSOME INVERSION
113

113 115 121 125

A. B.

MATERIALS AND METHODS

RESULTS

C. DISCUSSION

CONCLUSION

r

V
129 140

Literature Cited

Appendix

vi

LIST OF TABLES

Page

10

TABLE

I

Physical and chemical of the lakes. properties

TABLE II

Average water temperature in the

lake series.

27

TABLE III

The distribution of chironomids

in the one meter depth zone in

the lakes.

31

32

TABLE IV

The distribution of larvae unidentified to species.

TABLE

V

Summary of correlation coefficients describing therelationship between

environmental factors andthe

amount of emergence of certain

species.

76 77

The correlation between emergence

histogram dispersion and environmental

factors.

TABLE VI

TABLE VII Summary of correlation coefficients describing relationships between

environmental factors and species

abundance.

78

79 80 81 82

TABLE VIII Summary of correlation coefficients describing therelationship between

environmental factors and species per cent composition.

TABLE IX Summary of correlation coefficients describing therelationship between

environmental factors and the amount

of emergence.

TABLE

X

Summary of the correlation coefficients describing therelationship between

environmental factors and thenumber

of emergence peaks forvarious species.

TABLE XI Summary of correlation coefficients describing therelationship between

environmental factors and the times

of major emergence in several species.

VIX

TABLEXII Summary of correlation coefficients describing therelationship between

larval abundance, numbers of emerging adults, number of emergence peaks

and emergence time.

83 84

TABLE XIII

The developmental rates of C. tentans

in various lakes.

TABLE XIV

The percentage composition of species in the lakes based on the total adult

emergence, May - August, 1970.

90

Inversion frequencies inchromosome of C. tentans.

1

TABLE XV

116

Summary of correlation coefficients describing therelationship between

the frequency of 1 Rad and some

environmental factors.

TABLE XVI

117 118

119

120

TABLE XVII Summary of correlation coefficients describing therelationship between

the frequency of 1 Rad andthe

abundance of some chironomids.

TABLE XVIII Summary of correlation coefficients describing therelationship between

the frequency of 1 Rad and the per

cent composition of some chironomids,

Summary of correlation coefficients describing the relationship between

the frequency of 1 Rad and some

emergence variables.

TABLE XIX

v i i i

LIST OF FIGURES

Page

5

FIGURE FIGURE

12
The study area; Springhouse region. The study area; water bodies in the

Chilcotin region.

6

FIGURE FIGURE

34

Details of the emergence trap.

22
Daily temperature range in some of the lakes where Chironomus tentans

is

• abundant.
• 28

29

FIGURE FIGURE

56
Cumulative day degrees measured at the mud surface at a depth of 1 meter in some of the lakes where Chironomus tentans is abundant.

The emergence of adults of Procladius

bellus (Loew) and Procladius freemani Sublette from the one meter depth

zone of several lakes.

35 37

The emergence of adults of Procladius

dentus Roback from the one meter depth

zone of several lakes.

FIGURE FIGURE

78

The emergence of adults of Procladius clavus Roback and Ablabesmyia peleensis

(Whalley) from the one meter depth

zone of several lakes.

40 43 45
The emergence of adults of Cricotopus flavibasis Malloch and Cricotopus albanus Curran from the one meter

depth zone of several lakes.

FIGURE

9
The emergence of adults of Psectrocladius barbimanus (Edwards) from the one meter depth zone of

several lakes.

FIGURE 10 FIGURE 11

The emergence of adults of Crypto-

tendipes ariel (Sublette) and Calopsectra gracilenta (Holmgren)

from the one meter depth zone of

several lakes.

47

ix

FIGURE 12 Larval abundance and adult emergence

of Perotanypus alaskensis (Malloch)

in L. Lye, Boitano L. and L. Jackson.
50

51 55

FIGURE 13 Larval abundance and adult emergence

of Derotanypus alaskensis (Malloch)

in Rock L., Sorenson L. and East L.

FIGURE 14 Larval abundance and adult emergence of Einfeldia pagana Meigen in

L. Jackson, Rock L. and Westwick L.

FIGURE 15

Larval abundance and adult emergence of Einfeldia pagana Meigen in Near

Opposite Crescent, Barkley L. and East L.

56

FIGURE 16 Larval abundance and adult emergence

of Glyptotendipes barbipes (Staeger)

in L. Jackson, Westwick L. and

Sorenson L.

58 59 62

63

66 67 68

FIGURE 17

Larval abundance and adult emergence

of Glyptotendipes barbipes (Staeger)

in Rock L., Barkley L. and East L.

FIGURE 18 Larval abundance and adult emergence

of Chironomus anthracinus Zetterstedt in Boitano L., L. Jackson and Rock L.

Larval abundance and adult emergence

of Chironomus anthracinus Zetterstedt

in Sorenson L., Barkley L. and East L.

FIGURE 19

FIGURE 20 Larval abundance and adult emergence

of Chironomus n.sp. in Barnes L.,

Boitano L. and L. Jackson

FIGURE 21 Larval abundance and adult emergence of Chironomus n.sp. in Rock L. and

Sorenson L.

Larval abundance and adult emergence

of Chironomus n.sp. in Barkley L. and

East L.

FIGURE 22

FIGURE 23 Larval abundance and adult emergence of Chironomus tentans Fabricius in

L. Jackson, Westwick L. and Sorenson L. 74

FIGURE 24 Larval abundance and adult emergence

of Chironomus tentans Fabricius in

Rock L., Barkley L. and East L.

FIGURE 25 Chironomid larval biomass and index

of diversity forthe larval complexes

at 1.0 m in the lake series

FIGURE 26 Graph showing the relationship between

.

oxygen levels and organic carbon in the lakes.

FIGURE 27 Salinity tolerances of the identified

species of the one meter depth zone

in the lake series.

FIGURE 28 Examples of the spacing of emergence

times of Chironomus tentans and three

coexisting species.

FIGURE 29 Seasonal variation in the frequencies of inversions of chromosome 1.

LIST OF PLATES

Page

• 11
• Box 27

PLATE 1 A

B

Box 27;vegetation

12 13 14 15 16

21

PLATE 2 A

B

Barkley L. Barkley L.; Myriophyllum

PLATE 3 A

B

Near Phalarope Near Opposite Crescent

PLATE 4 A

B

L. Greer L. Jackson

L. Lye

PLATE 5 A

B

Round-up L.

Barnes L.

PLATE 6 A

B

Barnes L.; precipitated salts

The emergence trap

PLATE

7

x i i

ACKNOWLEDGEMENTS

It is

a

pleasure toexpress my gratitude to Professor
G.G.E. Scudder who, asmy research supervisor, guided me

through this work. The time and energy he spent aremuch

appreciated.
Dr. T.G. Northcote

1

scriticism was invaluable during the also thank Dr. A.B. Acton for reading

writing of thethesis.

I

the manuscript.

Dr.M.S. Topping, whose PhD. thesis served as

the basis for thepresent study, isespecially thanked forhis enthusiasm, support andpermission tousemuch ofhis unpub-

lished data.

Glen Jamieson, Tony Dixon andKen Bowler somehow put up

with my innumerable questions about computer programming. Without their help thedata analysis would have resembled an infinite loop, orworse, would have crashed thesystem.

Julian Reynolds, inbetween snickers, did a l l sorts of things to help.

I

am indebted toDr. J.E.Sublette (Eastern New Mexico
University) andDr. D.R. Oliver (Canada Agriculture, Ottawa)

for their help with thedeterminations.

Dr.A.M. Hutson

(British Museum: Natural History) kindly supplied authentic specimens of Einfeldia pagana andPsectrocladius barbimanus

for identification purposes.

The research was carried outwhile inreceipt ofa
National Research Council of Canada Postgraduate Scholarship and was further aided through an NRC grant toDr. Scudder.

ERRATA

1. Where "Aphanozomenon" appears, read "Aphanizomenon". 2. Page 26, l i n e 18. " 3 1 ° i n L. J a c k s o n " s h o u l d read

• " 3 1 °
• i n B a r k l e y L . " .

3. Page 61, l i n e 15. " u n i v o l t i v e " s h o u l d read " u n i v o l t i n e " . 4. Page 88, l i n e 17. "12000 umho/cm". 5. Page 1 0 2 , l i n e 18. " n o t r e a l t r e n d " s h o u l d read
"no r e a l t r e n d " .

6. Page 126, l i n e 2. " e i g h t e e n s p e c i e s new to B . C . , t w e l v e s p e c i e s new t o Canada and seven s p e c i e s new t o s c i e n c e " .

1

I

INTRODUCTION

This thesis is an ecological study of some of the

Chironomidae inhabiting

asaline lake series in the Chilcotin
The chironomid complex of a saline lake series has never been thoroughly examined before. Rawson and Moore (1944) and Lauer (1969) and Cariboo regions of British Columbia. have mentioned chironomids in connection with work on saline waters, and others have recorded and studied various species in waters of differing salinities throughout the world
(Remmert, 1955; Sutcliffe, 1960; Palmen, 1962; Bayly and Williams, 1966), but l i t t l e information has been gathered on how chironomid populations differ in a series of lakes of

varying

salinity.

This type of study is particularly interesting since i t is well known that chironomids display extensive adaptation to

• a
• wide variety of environments (Thienemann, 1954; Brundin, 1966)

and are often able to thrive where many other animals cannot.

The broad salinity tolerance of the Chironomidae gives them special prominence in saline habitats. This fact, in conjunction with their usual great abundance and wide diversity, makes chironomids useful organisms with which to study changes in the structure of species complexes that occur with varia-

tions in physical, chemical and biological conditions.

The data obtained by Topping (1969) on this lake series in central British Columbia showed that in the dipteran

2

Chironomus tentans Fabricius there was a significant corre-

lation between the frequency of larval chromosome inversion 1 Rad and the total number of other chironomids present in the

Since the selective value of inversions in wild pophabitat.

ulations is not clearly understood, and as there have been few

correlations of this sort, further investigation of this problem is considered valuable.

Although Topping was able to show this correlation between

inversion frequency and larval abundance, most emphasis was placed on the chemical composition of the environments and

l i t t l e attention was directed to the biotic factors involved.

Thus, one of the main aims of this thesis was to ascertain the effects of some biotic factors on the abundance of Chironomus

tentans and the implications of these factors on the regulation of inversion frequency.

In particular, i t was considered necessary to know more about the other chironomid species that coexist with C. tentans in this lake series, their numbers and their l i f e cycle

characteristics. Only after determining the variations in the

structure of the chironomid complex throughout the lake series

is i tpossible to place the populations of C. tentans in proper

perspective and to investigate the influence of the various

species on C. tentans.

I n i t i a l l y , attention is directed to the lake environments

themselves; their physical and chemical characteristics are outlined.
This information, in conjunction with extensive

3data collected on larval numbers and emergence patterns, is used in an examination of the major species of the one meter depth zone. Questions such as the effect of lake environments on the distribution and phenology of these species are discussed as are the possible interactions between the more domin-

ant species present.

The physical and chemical data are then integrated with information on chironomids and thus a description of a number of species associations is advanced.

These associations, vary-

ing throughout the lake environments, form the basis for the examination of the relationship between C. tentans and the other species.

With these data at hand the potential effect of the biotic factors on the chromosome inversion frequency in C. tentans may be more closely analyzed.

Correlation coefficients are

calculated to determine the types of interactions that may prove important In this respect.

Aparticularly interesting problem that arises from the study of interspecific interactions is the apparent coexistence with C. tentans of two other very similar Chironomus species, C. anthracinus Zetterstedt and C^n.sp. (near a t r i t i b i a Malloch). Attention is focussed on this congeneric interaction and competitive exclusion (Hardin, 1960) is discussed in this context.

4

II

THE LAKE ENVIRONMENTS
A. THE STUDY AREA

The study was undertaken intheCariboo and Chilcotin areas of central British Columbia.
The fifteen water bodies

examined are situated intwo distinct butadjacent areas: the Springhouse area southwest ofWilliams Lake east ofthe Fraser River; and Becher's Prairie near Riske Creek onthe

western (Chilcotin) side of theFraser (Figs. 1, 2). Those named as lakes canbe found on maps while theothers have

• names used for theconvenience of zoologists.
• The water bodies

include: a) Springhouse area: Sorenson Lake, Westwick Lake

• and Boitano Lake
• b) Becher's Prairie (Chilcotin Area): Barnes

Lake (Box4), Round-up Lake (Phalarope), Lake Lye (Box 20-21), Lake Jackson (Near Opposite Box 4), Lake Greer (Box89), Rock Lake, Near Phalarope, Near Opposite Crescent, Box 17, Barkley Lake (Opposite Box 4), East Lake (Racetrack) and Box27.

FIGURE

1
The Study Area: The three lakes in the Springhouse

region.

Insets

:

The Fraser Plateau and i t s

location in the province of British Columbia.

5