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ROYAL ONTARIO MUSEUM

LIFE SCIENCES
CONTRIBUTIONS

158

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Breeding-Bird
Populations
IN Jack Pine and
Mixed Jack Pine/
Deciduous Stands
IN Central Ontario

Ross D. James and Mark K. Peck

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Breeding-Bird Populations in Jack Pine
AND Mixed Jack Pine/Deciduous Stands

in Central Ontario

A mature jack pine (Pinus banksiana).
Illustration by Ross D. James.

Breeding-Bird Populations in Jack Pine
AND Mixed Jack Pine/Deciduous Stands

IN Central Ontario

Ross D. James
Mark K. Peck

ROYAL ONTARIO MUSEUM

retrieval system or data base, or transmitted, in any form or by any means, electronic,

mechanical, photocopying, or otherwise, without the prior written consent of the

publisher.

First published in 1995 by the Royal Ontario Museum, 100 Queen's Park, Toronto,
Ontario M5S 2C6.

Publication date: 1 May
ISBN: 0-88854-413-8
ISSN: 0384-8159

1995

Canadian Cataloguing in Publication Data

James, Ross D., 1943-

Breeding-bird populations in jack pine and
mixed jack pine/deciduous stands in central Ontario

(Life sciences contributions; no. 158)
Includes bibliographical references.
ISBN 0-88854-413-8

1. Forest birds - Ontario. 2. Birds - Ontario.
3. Jack pine - Ontario. 4. Birds - Ecology -
Ontario. 5. Bird populations - Ontario.
6. Forest management - Ontario. I. Peck, Mark K.
(Mark Kelday) , 1959- . II. Royal Ontario
Museum. III. Title. IV. Series.

QL685.5.06J3 1995 598.29' 152'097 13 C95-930597-1

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P-S.

ROYAL ONTARIO MUSEUM PUBLICATIONS IN LIFE SCIENCES
The Royal Ontario Museum publishes books on a variety of subjects in the life
sciences, including Life Sciences Contributions, a numbered series of original
scientific publications. All manuscripts considered for publication are subject to
the scrutiny and editorial policies of the Life Sciences Editorial Board, and to
independent refereeing by two or more persons, other than Museum staff, who
are authorities in the particular field involved.

LIFE SCIENCES EDITORIAL BOARD

Senior Editor: K. A. Coates

Editor: D. H. Collins

Editor: R. D. James

External Editor: C. S. Churcher

Manuscript Editor: K. A. Coates
Production Editor: Andrea Gallagher Ellis

Ross D. James is an associate curator in the Ornithology Department of the Royal
Ontario Museum.

Mark K. Peck is a technician in the Ornithology Department of the Royal Ontario
Mu.seum.

The Royal Ontario Museum is an agency of the Ontario Ministry of Culture,
Tourism and Recreation.

Cover: Yellow-rumped Warbler (Dendroica coronata) on a jack pine twig.
Illustration by Ross D. James.

Printed and bound in Canada

Contents

Abstract 1
Introduction 1
Methods 2

The Study Area 2

Habitat Data 8

Censuses 8
Resuhs 10

Censuses 10

Species Accounts 18
Discussion 23

The Pine Forest 24

The Mixed Pine/Deciduous Forest 26

Pine Forest vs. Mixed Forest 26

Population Changes 27

Forestry 27
Conclusions 29
Acknowledgements 30
Literature Cited 3 1

Digitized by the Internet Archive

in 2011 with funding from

Royal Ontario Museum

http://www.archive.org/details/breedingbirdpopuOOjame

Breeding-Bird Populations in
Jack Pine and Mixed Jack Pine/Deciduous Stands

in Central Ontario

Abstract

We studied breeding-bird populations between 1985 and 1992 in four different ages of
managed jack pine stands, and three different ages of jack pines mixed with birch and
aspen, in the Gogama area of central Ontario. We used variable-strip transect counts of
at least 1 km in length to gather information on bird-species presence and abundance
in different ages and compositions, and with supplementary observations we consid-
ered more specific habitat use by various species. This study also provided insight into
how forestry practices may be affecting bird populations in these forests.

Very young stands attracted open-country and early-successional species typical of
the area; only one of these species became part of the forest avifauna as stands
matured. By 20 years of age pine stands had an assemblage of nine core species well
established at maximum densities. These formed the dominant species at any age
thereafter. Three additional species joined them as characteristic of those pine forests
before 40 years of age. Other species were irregular and present only in small numbers
except during outbreaks of budworm. Five of the core species appeared to be present
in densities higher than expected in these managed, uniform-aged forests.

In contrast, in mixed forests at 20 years of age, many early-successional species
persisted, and many more species associated with deciduous forests had moved in, as
had many pine-dwelling species, so that population densities were overall at least dou-
ble that of pine forests of comparable age. Most of the population was composed of
deciduous-forest inhabitants; pine associates were comparatively few. As mixed
forests matured to 40 years of age, early-successional species left and additional forest-
dwelling species appeared. Overall species diversity was somewhat higher than in pine
forests, but overall abundance was about the same.

Managed, uniform-aged pine forests provided good habitat for a few species, and
bird populations appeared to be about the same as those found in typical boreal spruce
forests in Canada; however, the near-absence of cavity nesters suggested that forestry
practices were having a detrimental impact on these species.

Introduction

In the Boreal Forest Region of Canada, jack pine (Pinus Jack pine tends to form large and relatively uniform

banksiana) is the only pine species that covers extensive stands, particularly on xeric sites, often after fires (Moore,

areas (Moore, 1984). In Ontario it covers at least 15 per 1984). In central Ontario, it occurs naturally over large

cent of the areas subject to tree harvest (the proportion is districts (e.g., near Timmins, Kirkland Lake, Chapleau,

much higher in some parts) and is the second most impor- and Gogama; Howse, 1984). As the demand for this tree

tant commercial tree species (Howse, 1984). continues to grow, it is increasingly planted in uniform-

aged stands following clearcutting, and herbicide treat-
ment contributes to the development of pure pine stands
over extensive areas (Galloway, 1984).

Jack pine stands have received little study with respect
to bird populations, perhaps because no boreal bird
species rely solely on this habitat (Erskine, 1977), and
populations have been regarded as impoverished variants
of typical spruce-forest fauna (McLeod, 1967; Erskine,
1977). Knowing how many and which bird species are
present in these managed forests is relevant to several
questions about the potential effects of forest manage-
ment on bird populations. But the few censuses that have
been undertaken in boreal jack pine stands so far
(McLeod, 1967; Erskine, 1977) do little more than pro-
vide a background for further studies. There has been
increasing concern in recent years about widespread
declines in bird populations, particularly of neotropical
migrants, some of which summer in northern forests
(Terborgh, 1989; Robbins, Dawson, and Dowell, 1989).
We do not know whether forestry practices are negatively
affecting breeding-bird populations, but if they are, they
could also be contributing to an increase in the frequency
and severity of insect outbreaks. Jack pine is subject to
periodic infestations of jack pine budworm {Choris-

toneura pinus), jack pine sawfly {Neodiprion swainei),
and other insect pests (Howse, 1984), whose numbers can
be influenced by bird populations (Holmes, Schultz, and
Nothnagle, 1979; Mattson et al., 1968; Takekawa,
Garton, and Langelier, 1982).

The present study had the following aims: 1) to gather
information on bird-species presence and abundance in
one boreal forest community type, jack pines, during the
nesting season; 2) to see how bird-species composition
and abundance changed with the age of the pines; 3) to
see how bird-species composition and abundance was
influenced by the presence of deciduous growth among
the pines; and 4) to delineate more specific habitat use by
birds in association with pine stands.

From this study we also hoped to gain insight into how
forestry practices can be modified to benefit bird popula-
tions and thereby to take advantage of natural predators
for insect control. The information we gathered addresses
the general lack of bird-census data from boreal forest
areas, and the detailed background information from this
one area provides a basis of comparison that may some
day allow researchers to assess a long-term trend in bird
populations.

Methods

THE STUDY AREA

The study was conducted in central Ontario south of the
town of Gogama, Sudbury District, mainly along Hwy
560, east of its junction with Hwy 144 (47° 28' N, 81° 51'
W; Fig. 1). This area is within the Boreal Forest Region, a
continuous belt of primarily coniferous forest found
across most of the continent and comprising the greater
part of the forested area of Canada (Rowe, 1959). More
specifically it is the Missinaibi-Cabonga section which,
although basically boreal insofar as the bulk of the tree
species and their distributions are concerned, does contain
species from the Great Lakes-St. Lawrence region, either
as scattered individuals or as more or less isolated patches
(Rowe, 1959).

The predominant forest of the Missinaibi-Cabonga
section is mixed in character, consisting of an association
of balsam fir, black spruce, and white birch, with scat-
tered white spruce and trembling aspen (for plant names
see Table 1). However, in this section extensive sand and
gravel deposits provide a favourable environment for the
prevalent jack pine. This section occupies the height of
land between Hudson Bay and the Great Lakes. Its north-
ern boundary coincides generally with the northernmost
limits of white and red pine, yellow birch, and sugar

maple (Rowe, 1959). Along Hwy 560, large areas of
sandy soils together with other factors provide suitable
conditions for jack pine, which is naturally occurring
here. Areas readily accessible from the road now have
plantations of jack pines of various ages where natural
stands would otherwise be found.

Study efforts were concentrated in two broad cate-
gories of habitat: pine (P) and mixed pine/deciduous (M).
In four pine habitats, jack pine was of a fairly uniform
size and dispersion and very few trees of any other
species were present. In three mixed habitats, jack pine
was by far the dominant coniferous species and made up
about half of all trees present. Deciduous trees were
mainly trembling aspen and white birch. In the young
mixed habitat (M-2, see below), tall deciduous shrubs in
combination with deciduous trees exceeded pines in vol-
ume of foliage. However, in the medium-aged mixed
stand (M-3, see below), pines and deciduous trees were
about equal in numbers and habitat influence.

Censuses were obtained between 1985 and 1992 on
seven different areas. Three pine stands of seven, 20, and
39 years of age when censusing began, followed through
succeeding years, some for as long as eight years, gave a
fairly detailed sequence of bird-community changes

through the first half-century of the growth of these pine
plantations. Likewise, three mixed stands of roughly cor-
responding ages outlined the sequence of changes there.
A single older pine stand helped confirm that little change
is expected in bird populations in plantations more than
50 years old unless the forest is not harvested until after
trees reach maturity. The different areas are described
below.

P-1. New Growth of Pine (Fig. 2)

A very young pine plantation 3 km west of the junction of
Hwy 144 and Hwy 560 on the south side of the forestry
road to Sultan, about 25 km southwest of Gogama (UTM
squares 17MC3258, 3358, and 3357; map 41 P/5,
Invergarry Twp.).

Almost all growth above knee height here was small
jack pines. This was a dry, flat, gravelly area in which

pines were slow to grow. The pines seldom exceeded 1.5
m in height and were well spaced and fairly evenly dis-
tributed. The ground cover was largely sedges, blueberry
bushes, and trailing arbutus, with a few clumps of
Labrador tea and greenish mosses. A few snags persisted
adjacent to the census area.

A census was carried out in 1985 when the trees were
about seven years old. Some supplementary observations
were made here in 1989 but no formal census was con-
ducted.

P-2. Young Pine (Fig. 3)

A plantation of young pines, extending 0.5 to 5.5 km east
of Hwy 144, on the north side of Hwy 560, about 23 km
southwest of Gogama (UTM squares 17MC3758 and
3858; map 41 P/5, Vrooman Twp.).

This fairly uniform stand of jack pines was planted

TiMMINS

CHAPLEAU

GOGAMA
560

144

SUDBURY

)M-2

-•,-•■

A-,

iM-b

•
1

HWY

P-V-ip-2

^M-r>^

P-3

"■560

P-4

HWY

144

1 ITm

Fig. 1 . Maps of the study area showing the location of the censused areas.

9'-

Fig. 2. New growth of pines (P-1); trees were about seven years old when the area was
censused in 1985.

and/or aerially seeded and subsequently thinned to
remove almost all trees but pines. A small number of
trembling aspens persisted in a few tiny groves. One sec-
tion of pines about 100 m wide was very dense because it
was never thinned. A few white spruce, from seedlings to
nearly the same height as the pines, persisted. No stand-
ing dead trees were present in this area. Tall shrubs
(alder, willow, and pincherry) were thinly distributed
throughout the area. The ground had a nearly complete
cover of blueberry and sheep laurel as well as smaller
herbaceous plants and moss. Sedges and some Labrador
tea were found in a few places.

The ground was very level almost throughout.
Censuses were conducted yearly from 1985 to 1991. The
pines were about 20 years old in the first year of census-
ing. A number of nest boxes were placed in this habitat.
These were readily accepted by Boreal Chickadee and no
doubt contributed to the population.

P-3. Medium-aged Pine (Fig. 4)

A plantation of medium-aged pines on the south side of
Hwy 560, about 25 km east of Hwy 144 and 27 to 28 km
southeast of Gogama (UTM squares 17MC6057 and
6157; map 41 P/5, Garvey Twp.).

This area was almost pure jack pine, although a few
white spruce trees were found. There were almost no
dead trees standing in the entire area. Trees were relative-
ly evenly spaced and provided nearly complete canopy
cover. Tall deciduous shrubs (alder and pincherry) were
few to absent except for an occasional patch where they
were numerous. The ground was covered almost com-
pletely with sheep laurel and blueberry bushes amongst

which a variety of low herbaceous plants, lichens, and
mosses could be found.

This area was nearly level. Censuses were carried out
every year from 1985 to 1992. The trees were about 39
years old when censusing began.

P-4. Mature Pine (Fig. 5)

A managed area of fairly uniformly spaced, older jack
pines on the south side of Hwy 560, about 13 km east of
Hwy 144 and 22 to 23 km south of Gogama (UTM squares
17MC4757 and 4756; map 41 P/5, Westbrook Twp.).

This area was almost pure jack pine with a few white
spruce scattered throughout. Trees were more mature
than in area P-3, and somewhat more widely spaced, but
still relatively dense as is typical of a planted area. There
was an almost complete absence of dead standing snags.
Tall deciduous shrubs (pincherry and willow) were incon-
spicuous at best, but the ground was continuously cov-
ered with sheep laurel and blueberry bushes interspersed
with low herbaceous plants, lichens, and mosses.

The ground was nearly level. Only one census was
conducted here, in 1985, when trees were about 65 years
old.

M-1. New Growth of Mixed (Fig. 6)

A burned area on the north side of Hwy 560, about 9 km
east of Hwy 144 and 21 to 22 km south of Gogama (on
the east side of UTM square 17MC4458; map 41 P/5,
Vrooman Twp.).

Fire swept through this area of about 100 ha in 198 1 . It
was planted with jack pine seedlings in 1982 after most
standing dead trees were mechanically flattened. A few

Fig. 3. Young pine plantation (P-2) censused from 1985 to
1991 when trees were about 20 to 26 years old. Photo-
graphed in 1985.

Fig. 4. Medium-aged pines (P-3) censused from 1985 to
1992 when trees were about 39 to 46 years old.
Photographed in 1986.

Fig. 5. Mature pine trees (P-4) censused in 1985 when trees were about 65 years old.
Photographed in 1986.

Fig. 6. New growth of mixed trees (M-1) and shrubs censused from 1987 to 1989 and in
1991 and 1992 when pines were six to 1 1 years old. Photographed in 1987.

birch snags remained on level ground in the census area,
and numerous pine snags were left on steep hillsides out-
side the census area. Natural regeneration provided a
dense growth of tall deciduous shrubs (mainly alder and
pincherry) and young trees (primarily trembling aspen
with fewer white birch). This growth was about 1.5 m
high when censusing began in 1987, and exceeded 3 m in
1991. Blueberry, sheep laurel, honeysuckle, and sedges
covered much of the ground. A variety of herbaceous
plants, including bracken, filled in among the low shrubs
as the season progressed. Topography was relatively level
to gently rolling in the censused area, except for a deeper
ravine edge at one end of the transect.

Herbicide was sprayed on the area in 1986 to control
deciduous growth, but its effect was patchy and most
shrubs that were sprayed soon resprouted. Censuses were
conducted in 1987, 1988, 1989, 1991, and 1992, when
pines were six to 1 1 years old.

M-2. Young Mixed (Fig. 7)

A young mixed stand with planted pines on the east side
of Hwy 144, about 4 km north of Hwy 560 and 19 to 20
km southwest of Gogama (UTM squares 17MC3762 and
3763; map 41 P/12, Benneweis Twp.).

Jack pines were mixed with naturally occurring decid-
uous trees (white birch and trembling aspen) and these
were immersed in a vigorous growth of numerous tall
shrubs and tree saplings (alder, pincherry, willow, red
maple, mountain ash, white birch, and trembling aspen),
which were almost equal to the height of the pines in

some places. Some tall white birches had been left stand-
ing and were scattered here and there, either still alive or
providing tall snags. A few small black spruce and bal-
sam fir were also scattered throughout. Blueberry, brack-
en, and honeysuckle were the common ground covers.

The terrain was gently rolling with a few wet depres-
sions, and there were some swampy sections with tall
spruce adjacent to the censused area. Censuses were car-
ried out from 1985 to 1988 when trees were about 17 to
20 years of age.

M-3. Medium-aged Mixed (Fig. 8)

A medium-aged mixed forest immediately north of a nar-
row strip of planted pines on the north side of Hwy 560,
about 24 km east of Hwy 144 and 25 to 26 km southeast
of Gogama (UTM squares 17MC5858, 5958, and 6058;
map 41 P/5, Garvey Twp.).

Jack pines were mixed with about equal numbers of
deciduous trees, predominantly trembling aspen with
some white birch and white spruce. Pines and aspens
tended to form single-species groves rather than being
uniformly intermingled, indicating that planted pines had
not survived well on some parts of this undulating ground
with variable soil conditions. There were virtually no
standing dead trees here. Although trees were the domi-
nant taller vegetation, tall shrubs of pincherry and alder
were found scattered thinly throughout with a few dense
patches. The ground was densely covered with bracken in
most places, with some honeysuckle and blueberry. As
well, herbaceous plants were scattered throughout.

Fig. 7. Young mixed growth of pine, birch, and aspen (M-2) with numerous deciduous
shrubs, censused from 1985 to 1988 when trees were 17 to 20 years old. Photographed in
1986.

Fig. 8. Medium-aged mixed forest (M-3) censused from
1986 to 1988 when trees were about 40 to 42 years old.
Photographed in 1 986.

This strip of mixed forest was bounded on the north by
recently planted pines, heavily overgrown with deciduous
shrubs and tree saplings, and on the south by pine forest
of the same age. The topography was gently rolling.
Censuses were conducted from 1986 to 1988 when trees
were about 40 to 42 years old.

HABITAT DATA

Habitat data were gathered from 0.05 ha circles following
the method of James and Shugart (1970). Centres of cir-
cles were located at marked intervals along transect lines,
chosen by random number. Crown volume was estimated
according to Balda (1969), choosing trees by the point-
quarter method (Cottam and Curtis, 1956). Details of
stand characteristics are provided in Table 1. Ages of
trees were taken from Forest Resource Inventory maps.

In addition to birds recorded during censuses, at other
times during the study we noted the presence of several
additional species and supplemented our knowledge of all
species. Casual observations were also reported by others
working in this region. For 12 species that were charac-
teristically present in pines (Yellow-bellied Flycatcher,
Boreal Chickadee, Golden-crowned Kinglet, Hermit
Thrush, Solitary Vireo, Nashville Warbler, Yellow-
rumped Warbler, Blackburnian Warbler, Ovenbird,
Chipping Sparrow, White-throated Sparrow, and Dark-
eyed Junco) more specific habitat data were obtained in
order to describe more precisely the preferences of each
within the mosaic of available habitat. In general terms,
we recorded information on trees, shrubs, and ground
cover immediately surrounding male song perches, or, if
known, nest sites. We also noted the plant species pre-
sent, their proportions, heights, and spacing, and the
extent of ground cover.

CENSUSES

All censuses were conducted in stands that had tree
species of a similar age and covered an area of at least 40
ha. Bird populations were estimated with variable-strip
transect counts using song cues only and adjusting num-
bers by coefficients of lateral detectability and cue-fre-
quency production following methods outlined by Emlen
(1971, 1977) and Christman (1984). This procedure is
useful only for songbirds, although we made a note of
other species seen, and counts for drumming grouse were
likely as accurate as those for songbirds. Where sample

sizes were very small, the maximum count rather than an
average count was used, adjusting only by a lateral-detec-
tion factor as necessary.

Transects (one per habitat type) were measured with a
stout cord and were marked every 50 m with surveyor's
flagging tape. To minimize bias associated with small
sample areas, transects were at least 1 km long if possi-
ble. By using transects that were at least 1 km long, we
effectively sampled an area of at least 20 ha (100 m on
either side of the transect line) for most species. This
exceeded the minimum area quoted by Erskine (1977) of
16 ha. And to minimize the bias associated with small
plot sizes (Engstrom, 1981; Engel-Wilson et al., 1981),
where possible we used a transect 2 km long, sampling an
area of 40 ha. This ensured that even for species with
rather quiet songs (Golden-crowned Kinglet and Boreal
Chickadee) where we sampled only 30 m on either side of the
transect, we still had an effective sampUng area of 12 ha. For
all other species the sampling area was 20 ha or more.

To minimize error associated with distance estimating,
birds were not counted beyond 100 m from the transect
line, although many could be heard much farther away.
To facilitate comparisons among areas and with other
workers, estimates for sample areas were adjusted to a
standard value of the number of pairs of birds per square
kilometre (pr/km'^). Each transect was walked six times at
a rate of 1 km/h, beginning between 0530 and 0630 h
EDST. Half the counts were begun at one end of each
transect, the other half at the other end. Whenever possi-
ble, in any one habitat simultaneous counts were made by
two observers starting at opposite ends of the transect,
and counting was done on successive days. Thus, weather
permitting, all counts in any one habitat were made in a
three-day period, to minimize changes associated with
changing time of year. Counts were conducted between
26 May and 15 June and an effort was made to census the
same stands on the same dates in subsequent years. Rainy
or excessively windy days were avoided, calm, humid
conditions being typical in this area at this time of year.
Similarity coefficients between census areas were calcu-
lated following the methods of Gillespie and Kendeigh
(1982).

Bird species names and sequence are those of the
American Ornithologists' Union Check-list of North
American Birds, 6th ed. (1983) and any subsequent sup-
plements. Scientific names are found in the species
accounts.

Table 1. Habitat characteristics of seven censused stands (P-1 to P-4, M-1 to M-3) in the Gogama area, Sudbury District, Ontario.

P-1

P-2

P-3

P-4

M-1

M-2

M-3

Year data gathered

1985

1988

1985-

1986

Age of pines (years)

No. of 0.05 ha samples

No. of trees (>5 cm DBH)/ha

—

1768

1612

722

—

664

1749

Basal area (m^/ha)

—

11.5

28.7

—

4.15

30.1

Relative density (%)

—

Pj— 99.3

Pj 100

Pj 94.5

—

Pj— 47.2

Pj^l8.8

At 0.7

Sw— 5.5

Fb^l.l
Bw— 40.8

At— 36.7
Bw— 13.5

At— 1.2
Sw 6.6

Sw 0.7
H 0.2

Relative dominance (%)

—

Pj— 99.5

Pj— 100

Pj— 97.9

—

Pj— 66.7

Pj 55.6

At 0.5

Sw— 2.1

Bw— 23.6
Fb 8.2
At 0.01
Sw 0.01

At— 35.5
Bw— 8.8

Relative frequency (%)

—

Pj— 100

—

Pj— 100

Pj 83

At— 33

Sw— 80

Bw— 50
At— 33
Fb 33
Sw— 17

At 66
Bw— 100
Sw 66
H— 17

Mean canopy height (m)

—

7.3

15.3

20.2

—

6.3

16.5

Range of canopy height (m)

— -

6-8

14-16

18-22

—

6-7

10-18

Trees>15cmDBH(%)

—

0.56

39.3

80.6

—

58.3

Trees>30cmDBH(%)

—

0.2

8.8

—

Canopy cover (%)

—

65.8

63.3

—

91.6

Mean height to low branches (m)

—

1.9

7.1

8.3

—

1.1

8.6

Range height to low branches (m)

—

1-3

3-11

0-15

—

0.5-2

3-13

Crown volume

— mean/tree (m~^)

—

3.56

15.6

22.2

—

3.1

15.6

— per ha (m^)

—

6294

25147

15163

—

2058

27284

— range/tree (m^)

—

0.65-14

1-78

1.3-54

—

0.3-6.5

1.2-65.4

Shrub stems per ha

3839

5308

4450

2700

21316

41900

7933

Shrub height (m)

0.5-2.5

1-3

0.5-3

0.5^.5

2-4

Shrub species (with %)

Pj 99

Pj— 33

Pj— 10

P^l^^^-^y 100
willow j

Pj— 12

Pj— 10

Pj 1

willow 1

alder

pincherry

aspen

alder »

serviceberryj

spruce

alder
■ 66 willow

pincherry

willow

serviceberry

88 Bw
willow

pincherry

alder

90 alder

spruce

willow

maple

mountain ash
90 ^

Ground cover (%)

100

Height of ground cover (m)

0.1

0.3

0.5

Dominant cover species

sedges

blueberry

sheep laur

el sheep laurel

blueberry

bracken

blueberry

sheep laur

si blueberry

blueberry

bracken

honeysuckle

trailing arbutus

Labrador t

ea lichens

lichens

honeysuckle

blueberry

Labrador tea

sedges

moss

herbs

moss

honeysucl
herbs

:le herbs

sedges
sheep laurel
raspberry
sweetfem
herbs

willow
mountain ash
Labrador tea
herbs

Specific nomenclature from Gleason and Cronquist (1963)

Pj — pine, jack — Pinus banksiana

— pine, red — Pinus resinosa

— pine, white — Pinus strobus
At — aspen, trembling — Populus tremuloides
Bw— birch, white — Betula papyrifera

— birch, yellow— Bem/a lutea
Sw — spruce, white — Picea glauca

Sb — spruce, black — Picea mariana
Fb — fir, haham— Abies balsamaea
H — hemlock — Tsuga canadensis
maple — Acer sp.
maple, sugar— Acer saccharum
mountain ash — Sorbus sp.
Labrador tea — Ledum groenlandicum

blueberry — Vaccinium sp.

sheep laurel — Kalmia angustifolia

bracken — Pteridium aqualinum

honeysuckle — Diervilla lonicera

sedges — Cyperaceae

mosses — Musci

lichens — Thallophyta

raspberry — Rubus sp.
sweetfem — Myrica asplenifolia
trailing arbutus — Epigaea repens
willow — Salix sp.
pincherry — Prunus pensylvanica
alder — AInus sp.
serviceberry — Amelanchier sp.

Results

CENSUSES

P-1. New Growth of Pine (Fig. 2)

A comparison of censused areas with respect to the birds
found is presented in Table 2. In the new growth of pines
the population of birds was the lowest of any of the cen-
sused areas (Table 3). Half the population was made up of
a single species (White-throated Sparrow), a species that
prefers edges and early-successional stages. The bird
community was largely that of a field/shrub habitat rather
than a wooded environment. Several species noted
(Vesper Sparrow, Northern Harrier, American Kestrel,
and Northern Flicker) require very open habitats with
exposed ground while others (Brown Thrasher, Yellow
Warbler, Chestnut-sided Warbler, and Song Sparrow)
were attracted by patches of deciduous shrubby habitat.
Species foraging predominantly in trees were scarcely
seen and contributed nothing to the population size. There
was a relatively low similarity to any other censused area
(Table 2); the most similar was M-1, also an early-succes-
sional stage but with much more deciduous growth cover-
ing the ground.

P-2. Young Pine (Fig. 3)

In the young pine woods several species were remnants
from the fauna of a younger, more open habitat (Northern
Harrier, Northern Flicker, Common Yellowthroat, and
Lincoln's Sparrow) or of more deciduous shrub growth
(Alder Flycatcher and Chestnut-sided Warbler; Table 4).
Species that were characteristically attracted to deciduous
tree growth were either absent or present only in very
small numbers (Table 2) where remnant patches of such
vegetation were still present (Black-capped Chickadee,
Veery, American Redstart, and Red-eyed Vireo).

The number of species inhabiting trees in P-2 was sub-
stantially greater than in P-1 (Table 2). Trees were still
too small to be attractive to Solitary Vireo and
Blackbumian Warbler, and Golden-crowned Kinglet was
only beginning to appear. But six forest dwellers
(Yellow-bellied Flycatcher, Boreal Chickadee, Hermit
Thrush, Nashville Warbler, Yellow-rumped Warbler, and
Ovenbird) were well established and could be as abun-
dant here as in any other censused area (Table 4).
Chipping Sparrow and White-throated Sparrow showed
declines as the forest matured and closed in, whereas
Dark-eyed Junco increased during the same time, but was
also part of a core component of pine-dwelling species.

In young pines (P-2) the number of species was lower
and population levels were only half that found in simi-
larly aged mixed pine/deciduous woods (M-2; Table 2).
Species such as Red-eyed Vireo, Chestnut-sided Warbler,

and American Redstart were much more numerous in
mixed woods. Likewise, Rose-breasted Grosbeak, Canada
Warbler, Mourning Warbler, and Black-and-white
Warbler were present only in mixed woods. It is clear that
a habitat component associated with deciduous growth
was excluded in a growth of almost pure pines. The area
of young pines, as might be expected, was most similar to
the area of medium-aged pines (P-3; Table 2). However,
there was also a fairly high similarity to similarly aged
mixed woods (M-2), because many of the same species
would be attracted to pines in both areas (compare Tables
4 and 8).

P-3. Medium-aged Pine (Fig. 4)

In pine forest of medium age a suite of 12 forest-inhabit-
ing species formed the bulk of the population each year
(Yellow-bellied Flycatcher, Boreal Chickadee, Golden-
crowned Kinglet, Hermit Thrush, Solitary Vireo,
Nashville Warbler, Yellow-rumped Warbler,
Blackburnian Warbler, Ovenbird, Chipping Sparrow,
White-throated Sparrow, and Dark-eyed Junco), whereas
most other species occurred only sporadically or in small
numbers (Table 5). In 1985 jack pine budworm in epi-
demic numbers contributed to very high numbers of Bay-
breasted Warbler in P-3 and P-4. Although some
Tennessee Warbler, crossbills, and possibly other species
may have been attracted in by budworm. Bay-breasted
Warbler was the only species obviously contributing sig-
nificantly to increased population levels. We have there-
fore excluded their numbers from the calculation of mean
density (Table 2) so that the influence of this unusual sit-
uation is removed. Budworm numbers dropped much
lower in 1986 and virtually disappeared in succeeding
years (MacLeod, Jones, and Keizer, 1985, 1986;
MacLeod, Jansons, and Keizer, 1987; MacLeod, Jansons,
and Payne, 1988, 1989).

Although the area most similar to P-3 (medium-aged
pine) was P-2 (young pine), the proportion of tree for-
agers had increased in P-3 to about two-thirds, compared
to half in young pines. The similarity was almost as high
with mature pines (P-4, Table 6) because tree foragers
using pines accounted for most of the population in these
three pine stands (Table 2). Adjacent mixed forest of the
same age (M-3) had only a few more species and about
the same population levels; however, the numbers of
deciduous-foraging species accounted for about half the
population total. The similarity coefficient is fairiy high
since many of the pine-dwelling species were the same in
both areas (compare Tables 5 and 9).

Table 2. Comparison of bird populations in the seven censused areas.

P-1

P-2

P-3

P-4

M-1

M-2

M-3

No. of years censused

Age of pines (years)

20-27

39-^7

7-12

17-20

40^3

Mean no. of bird species

Mean density of birds (pairs/km-)

141

334

350'

315*

361

791

380

No. of tree-foraging birds

— percentage of mean density

-1-

Tree foragers mainly using pine

— percentage of mean density

98*

100*

Tree foragers mainly using deciduous

— percentage of mean density

No. of ground- and shrub-foraging birds

— percentage of mean density

100

No. of aerial foragers

— percentage of mean density

-1-

Similarity coefficients (%) compared

with
P-2
P-3
P-4

42
38
24

78
66

M-1

M-2

M-3

* excluding Bay-breasted Warbler

Table 3. Census results (males or pairs/km^) from a
new growth of jack pines (P-1). A transect 1.9 km
long was used in this open habitat where pines were
about seven years old.

1985

Northern Harrier
American Kestrel
Ruby-throated Hummingbird
Northern Flicker
Tree Swallow
Blue Jay
Common Raven
Swainson's Thrush
Hermit Thrush
American Robin
Brown Thrasher
Yellow Warbler
Chestnut-sided Warbler
Chipping Sparrow
Clay-colored Sparrow
Vesper Sparrow
Song Sparrow
White-throated Sparrow
Dark-eyed Junco
Purple Finch

-I-

5.3

7.9

5.3

7.9

-I-

18.4

15.8

69.8

10.5

TOTAL

141

Table 4. Census results (males or pairs/km^) from a young pine woods (P-2). A transect 2 km long was used in all years. Trees
were mainly 20 years old when censusing began, but a small section on the western end was 17 years old.

1985

1986

1987

1988

1989

1990

1991

Northern Harrier

Sharp-shinned Hawk

—

Spruce Grouse

-1-

—

Northern Flicker

—

-1-

—

Yellow-bellied Rycatcher

24.0

14.9

5.5

9.2

19.5

9.4

13.2

Alder Flycatcher

5.0

2.5

—

Gray Jay

—

Blue Jay

—

-1-

—

American Crow

—

Common Raven

—

-t-

—

Black-capped Chickadee

—

Boreal Chickadee

15.0

—

16.5

28.5

33.0

—

8.3

Red-breasted Nuthatch

—

-1-

—

Golden-crowned Kinglet

—

5.0

-1-

10.0

15.0

Ruby-crowned Kinglet

-1-

—

2.5

—

Veery

—

-1-

—

Swainson's Thrush

18.5

2.5

7.5

—

7.5

Hermit Thrush

31.7

38.7

47.3

30.7

52.0

37.5

46.1

American Robin

5.0

2.5

—

Cedar Waxwing

—

-t-

—

Solitary Vireo

-1-

—

2.5

—

Red-eyed Vireo

10.0

5.0

Tennessee Warbler

—

5.0

6.7

—

Nashville Warbler

65.0

97.5

66.5

42.6

60.5

73.1

51.7

Chestnut-sided Warbler

10.0

-t-

—

Magnolia Warbler

13.3

-1-

6.5

-H

Yellow-rumped Warbler

41.1

52.0

74.9

53.0

65.0

63.4

73.0

Blackbumian Warbler

—

-1-

—

American Redstart

-H

—

Ovenbird

16.0

26.0

31.6

29.4

36.5

43.9

46.3

Common Yellowthroat

-1-

—

Chipping Sparrow

20.0

15.0

50.0

30.0

15.0

10.0

17.7

Lincoln's Sparrow

—

White-throated Sparrow

50.0

53.5

53.1

27.5

25.3

7.5

9.8

Dark-eyed Junco

20.0

18.9

32.9

31.1

20.3

35.0

62.5

Purple Finch

—

Crossbill sp.

—

Evening Grosbeak

—

TOTAL

345

329

395

296

335

290

354

Table 5. Census results (males or pairs/km^) from a forest of jack pine trees of about 39 years of age when censusing began (P-3).
Results were from a transect 2 km long.

1985

1986

1987

1988

1989

1990

1991

1992

Broad-winged Hawk

—

Spruce Grouse

-1-

—

-1-

Northern Flicker

—

Yellow-bellied Flycatcher

16.5

5.0

7.5

2.5

20.9

10.0

5.0

—

Gray Jay

-1-

—

-1-

—

Blue Jay

-1-

—

Common Raven

—

-1-

—

Black-capped Chickadee

—

-t-

—

Boreal Chickadee

8.3

5.0

2.5

16.5

2.5

10.0

16.5

Red-breasted Nuthatch

5.0

7.5

—

Brown Creeper

—

-1-

—

2.5

Winter Wren

—

2.5

—

Golden-crowned Kinglet

—

5.0

20.0

15.0

5.0

15.0

Ruby-crowned Kinglet

—

-1-

Swainson's Thrush

—

2.5

—

Hermit Thrush

23.8

25.6

27.5

20.0

40.5

30.1

20.0

41.5

American Robin

—

Cedar Waxwing

—

-1-

—

-1-

Solitary Vireo

5.0

12.5

15.0

12.5

7.5

2.5

5.0

Red-eyed Vireo

5.0

-1-

—

Tennessee Warbler

2.5

10.4

—

Nashville Warbler

53.5

89.4

24.4

11.5

37.1

30.4

13.3

6.5

Yellow-rumped Warbler

62.7

28.9

28.3

31.8

50.0

31.0

55.5

65.0

Blackbumian Warbler

92.8

91.7

74.5

37.9

63.0

54.1

38.0

50.0

Bay-breasted Warbler

192.1

2.5

—

Ovenbird

69.8

115.8

70.4

76.2

68.5

70.6

40.9

49.0

Connecticut Warbler

—

2.5

-1-

—

-H

Chipping Sparrow

30.0

25.0

28.9

2.5

10.0

17.7

—

3.2

White-throated Sparrow

25.0

24.1

25.0

15.0

12.5

8.3

24.8

66.0

Dark-eyed Junco

24.9

27.8

34.8

17.7

34.5

23.2

25.0

40.0

Purple Finch

—

Crossbill sp.

—

Evening Grosbeak

7.5

-1-

TOTAL

624

474

351

267

381

300

240

360

OWTAR/0

X A

P-4. Mature Pine (Tig. 5)

The somewhat more open nature of the mature pine forest
may account for the high numbers of Chipping Sparrow.
Noticeably scarce to absent in the young to mature pine
forest were cavity nesters, particularly woodpeckers. The
most numerous was the Boreal Chickadee, which needs
only very small cavities. Even at that, we located only
one natural nest in the centre of an old stump. The nest
itself was actually below ground level. Suitable snags or
dead trees for any of the cavity nesters were virtually
absent in this type of managed forest.

M-1. New Growth of Mixed (Fig. 6)

Mixed growth at a young early-successional stage was
dominated by two species that appear as soon as a sub-
stantial cover of vegetation develops (White-throated
Sparrow and Common Yellowthroat; Table 7). As shrub
growth increased in height. Alder Flycatcher and
Chestnut-sided Warbler soon became as common.
Lincoln's Sparrow and Mourning Warbler also found
some suitable habitat. As vegetation reached about 3 m in
height, species more typical of older woodlands — Ruffed
Grouse, Veery, Hermit Thrush, Red-eyed Vireo, and
Nashville Warbler — began to appear (compare Tables 7
and 8). The population was still heavily dominated by
ground and shrub foragers. Early-successional species
could be very common (100 to 200 pr/km^) and popula-
tion levels were substantial at this stage, even though only
a few species contributed to the bulk of the numbers.

M-2. Young Mixed (Fig. 7)

In the mixed growth of young pines and deciduous trees
with numerous shrubs, many more bird species found
suitable habitat (Table 8), and some additional species
wandered into the area from adjacent habitat. Early-suc-
cessional species, such as Alder Flycatcher, Chestnut-
sided Warbler, and White-throated Sparrow, were still
common to abundant, but declined as the trees matured,
while Common Yellowthroat, Mourning Warbler, and
Lincoln's Sparrow were gone or nearly gone.

Several new mid-successional species, such as Blue
Jay, Magnolia Warbler, Black-and-white Warbler, and
American Redstart, had become common. The number of
species that would persist as the forest matured, including
Ruffed Grouse, Yellow-bellied Flycatcher, Blue Jay,
Black-capped Chickadee, Red-breasted Nuthatch, Winter
Wren, Veery, Swainson's Thrush, Hermit Thrush, Red-
eyed Vireo, Nashville Warbler, Yellow-rumped Warbler,

Rose-breasted Grosbeak, and Evening Grosbeak, had
increased substantially. The woods were still dominated
by ground- and shrub-foraging species; of species attract-
ed by tree growth, nearly 60 per cent were those favour-
ing deciduous components (Table 2).

In M-2 several cavity nesters (Downy Woodpecker,
Hairy Woodpecker, Northern Flicker, Tree Swallow,
Black-capped Chickadee, and Red-breasted Nuthatch)
were undoubtedly attracted by the standing dead trees.
The increasing populations of forest dwellers, with the
still substantial population of early-successional species,
plus the combination of coniferous and deciduous trees,
contributed to the highest densities and the greatest num-
ber of species recorded among any of the areas censused.

M-3. Medium-aged Mixed (Fig. 8)

In the medium-aged mixed forest of jack pines with trem-
bling aspens and white birches where trees were in excess
of 10 m in height, some of the diversity of a younger
mixed wood had gone (Table 9). The number of early-
successional species that had left was greater than the
number of late-successional species that had arrived.
Least Flycatcher, Philadelphia Vireo, Black-throated Blue
Warbler, Blackburnian Warbler, and Ovenbird were the
main additions. A very few Golden-crowned Kinglet,
Solitary Vireo, Tennessee Warbler, Scarlet Tanager, and
Dark-eyed Junco occurred where pockets of forest were
suitable for at least occasional use. In this forest there
were now more tree than ground and shrub foragers, but
they made up about equal proportions of the population
(Table 2).

In the pine forests (20 or more years old), we recorded
about 20 species a year regardless of age, usually the
same species. An additional 18 species were recorded
over a number of years, but in general they contributed
little to the overall population. There was considerable
difference, however, in both species numbers and popula-
tion sizes recorded between the 20-year-old and the 40-
year-old mixed forests, with the more gradual disappear-
ance of early-successional species and a concomitant
appearance of other species. The bird community also
seemed more dynamic in mixed forests; while more
species were likely to be recorded in any one year (as
many as 30 in any given year and nearly 50 over several
years), the numbers of any one species present seemed to
fluctuate considerably. Even for the half-dozen species
likely to be recorded every year, numbers were not
always substantial.

Table 6. Census results (males or pairs/km^) in a
mature pine forest of about 65 years of age (P-4). A
transect 1 .5 km long was used.

1985

Sharp-shinned Hawk +

Yellow-bellied Flycatcher 3.3

Gray Jay +

Black-capped Chickadee +

Boreal Chickadee 3.3

Red-breasted Nuthatch 6.7

Hermit Thrush 18.7

Solitary Vireo +

Tennessee Warbler 6.7

Nashville Warbler 22.1

Yellow-rumped Warbler 61.2

Blackbumian Warbler 63.4

Bay-breasted Warbler 77.7

Ovenbird 23.4

Chipping Sparrow 73.3

White-throated Sparrow 20.5

Dark-eyed Junco 10.0

Purple Finch 3.3

Crossbill sp. +

Evening Grosbeak +

TOTAL 393

Table 7. Census results (males or pairs/km^) for a new growth of jack pines mixed with deciduous
regeneration (M-1). Trees were six years old when censusing began. A transect 1 km long was used in
this early-successional stage.

1987

1988

1989

1991

1992

Mallard

Red-tailed Hawk

—

American Kestrel

■ — •

—

Ruffed Grouse

—

5.0

—

Ruby-throated Hummingbird

—

Northern Flicker

-1-

Alder Flycatcher

—

33.3

112.0

5.0

Eastern Kingbird

—

Tree Swallow

—

Blue Jay

—

Common Raven

—

Veery

—

10.0

15.0

—

Hermit Thrush

—

10.0

5.0

—

American Robin

—

10.0

—

Brown Thrasher

— -

—

5.0

—

5.0

Cedar Waxwing

—

Red-eyed Vireo

—

20.0

5.0

Nashville Warbler

—

5.0

13.0

39.0

Chestnut-sided Warbler

—

5.0

15.0

70.0

30.0

Yellow-rumped Warbler

—

20.0

Mourning Warbler

30.2

5.0

15.0

30.0

Common Yellowthroat

105.4

100.9

66.7

91.8

37.5

Lincoln's Sparrow

10.0

20.0

5.0

10.0

White-throated Sparrow

200.0

125.0

50.0

196.2

247.0

Dark-eyed Junco

—

10.0

TOTAL

346

251

230

538

439

Table 8. Census results (males or pairs/km-^) from a young mixed jack pine/deciduous
woods (M-2). Trees were 17 years old when censusing began. A transect 1.5 km long
was used.

1985

1986

1987

1988

American Kestrel

,_^

Ruffed Grouse

5.0

6.6

22.0

19.8

Common Snipe

—

Yellow-bellied Sapsucker

—

Downy Woodpecker

—

Hairy Woodpecker

-1-

—

3.3

Northern Flicker

15.4

—

Olive-sided Flycatcher

—

Yellow-bellied Flycatcher

5.0

3.3

6.6

—

Alder Flycatcher

73.5

34.3

19.8

13.2

Least Flycatcher

15.0

3.3

—

Tree Swallow

—

Gray Jay

-1-

— "

Blue Jay

5.0

6.6

3.3

American Crow

—

Black-capped Chickadee

—

6.6

19.8

Red-breasted Nuthatch

—

6.6

Winter Wren

—

6.6

3.3

Ruby-crowned Kinglet

-1-

—

Eastern Bluebird

—

Veery

28.5

26.5

13.2

20.0

Swainson's Thrush

—

31.5

48.0

19.9

Hermit Thrush

36.0

24.6

20.5

26.3

American Robin

25.0

11.7

19.9

10.0

Cedar Waxwing

-1-

—

-1-

Solitary Vireo

—

Red-eyed Vireo

67.2

66.6

60.5

56.0

Nashville Warbler

53.2

50.4

42.9

40.6

Chestnut-sided Warbler

460.3

109.6

134.4

110.0

Magnolia Warbler

46.7

89.5

83.7

90.2

Yellow-rumped Warbler

20.0

44.2

26.1

21.5

Black-throated Green Warbler

—

Black-and-white Warbler

45.4

25.4

39.1

19.8

American Redstart

85.3

46.0

91.7

66.0

Mourning Warbler

15.0

9.9

—

Common Yellowthroat

5.0

-1-

6.6

—

Canada Warbler

10.0

13.2

—

Rose-breasted Grosbeak

25.0

3.3

10.0

Chipping Sparrow

5.0

—

White-throated Sparrow

109.1

69.3

61.9

37.9

Dark-eyed Junco

—

3.3

13.2

Rusty Blackbird

—

Common Grackle

—

Purple Finch

—

Crossbill sp.

—

American Goldfinch

—

Evening Grosbeak

—

TOTAL

1140

682

732

611

Table 9. Census results (males or pairs/km-) from a mixed jack
pine/deciduous forest that was about 40 years old when censusing began
(M-3). A transect 2 km long traversed this stand.

1986

1987

1988

Ruffed Grouse

7.5

10.0

Yellow-bellied Sapsucker

-1-

—

Pileated Woodpecker

—

-1-

—

Yellow-bellied Flycatcher

—

-1-

10.0

Least Flycatcher

42.5

38.3

32.3

Blue Jay

—

5.0

Black-capped Chickadee

20.0

7.5

10.0

Red-breasted Nuthatch

5.0

—

2.5

Winter Wren

5.0

2.5

Golden-crowned Kinglet

—

2.5

Ruby-crowned Kinglet

—

-1-

—

Veery

—

19.0

10.0

Swainson's Thrush

7.5

10.0

Hermit Thrush

17.5

5.0

Cedar Waxwing

—

-H

Solitary Vireo

—

2.5

Philadelphia Vireo

10.0

23.0

21.3

Red-eyed Vireo

69.7

47.2

25.0

Tennessee Warbler

2.5

—

Nashville Warbler

36.3

19.6

2.5

Magnolia Warbler

5.0

2.5

Black-throated Blue Warbler

20.5

21.5

15.0

Yellow-rumped Warbler

19.9

5.0

Blackbumian Warbler

61.8

59.6

23.3

Black-and-white Warbler

10.0

—

2.5

Ovenbird

136.5

99.5

65.1

Scarlet Tanager

5.0

2.5

6.7

Rose-breasted Grosbeak

5.0

—

White-throated Sparrow

12.5

—

Dark-eyed Junco

2.5

—

Purple Finch

—

Evening Grosbeak

—

TOTAL

497

371

271

SPECIES ACCOUNTS

We noted 80 different bird species while working in vari-
ous ages of pine or mixed pine/deciduous forests during
the breeding season, and an additional three species were
reported to us. About half of these 83 species made spe-
cific use of pines to some extent. Of those using pines,
only 20 species made extensive use of pine forest,
although two of these were present only when budworm
levels were high. Others, while largely associated with
openings in the canopy or with deciduous growth, did
make some use of pines, especially areas regrowing with
pines.

American Black Duck, Anas rubripes

Rare in wooded areas; found nesting once in an area with
young pines some distance from water.

Mallard, Anas platyrhynchos

Rare in wooded areas; apparently looked for nesting
cover in young open pine regeneration near lakes, where
the species has been known to nest (Peck and James,
1983).

Northern Harrier, Circus cyaneus

Rare, found nesting adjacent to, and frequently seen hunt-
ing in, young regeneration, where there was still open
space between trees.

Sharp-shinned Hawk, Accipiter striatus

Rare, but seen more frequently than Northern Harrier;
seen in pines of any height above 6 m. Several unoccu-
pied nests seen in pines 40 to 50 years old may have been
constructed by this species.

Northern Goshawk, Accipiter gentilis

Rare, but known to hunt in any pine forest once trees
reached about 6 m in height. One nest site reported in a
patch of mature to overmature jack pines.

Broad- winged Hawk, Buteo platypterus

Seen rarely; found nesting in a mature jack pine in a
mixed forest. Typically hunts in deciduous components of
a forest, but not exclusively so.

Red-tailed Hawk, Buteo jamaicensis

Relatively rare; seen hunting over very young regenera-
tion and found nesting in a thin strip of mature jack pine
trees beside a bog.

American Kestrel, Falco sparverius

Rare, but easily seen; nested in old woodpecker cavities
in large snags left standing in cutovers or burns. Hunted
near their nests in open areas, and could be expected in
any such area of 50 or more ha.

Merlin, Falco columbarius

Very rare; found nesting in a jack pine grove with trees
about 15 m high, near openings, where they prefer to
hunt.

Spruce Grouse, Dendragapus canadensis

A characteristic bird of jack pine forests. Began to appear
in pines by the time trees reached 2 m in height and was
at maximum abundance in young pines (P-2). Trees of 1 1
to 21 years old in the Gogama area had the highest densi-
ties of Spruce Grouse recorded anywhere in North
America (Szuba and Bendell, 1983). Populations decline
as the forests mature.

Ruffed Grouse, Bonasa umbellus

A relatively common species, preferring the deciduous
components of mixed pine/deciduous forests. Began to
occur when deciduous growth exceeded 2 m in height;
appeared to reach maximum densities in younger forests
of about 20 years old.

Solitary Sandpiper, Tringa solitaria

Rare; seen several times in summer in a beaver-flooded
area surrounded by young pine woods, where it could
have nested.

Common Snipe, Gallinago gallinago

Rare; attracted only by wet depressions with standing
water among trees.

Great Gray Owl, Strix nebulosa

Young of the year reported in a 40-year-old pine forest.
This rare species could have nested, and certainly could
hunt, in this forest. Also observed in winter in adjacent
mixed pine/deciduous forest.

Short-eared Owl, Asio Jlammeus

Rare; may have been only a migrant, but was reported
from a newly planted area with grasses and sedges, where
the open nature of the habitat afforded the species
favourable conditions.

Common Nighthawk, Chordeiles minor

Uncommon; usually seen foraging in the air over pines,
especially recently planted areas, and younger woods.
Could have nested in such areas where trees were not yet
contiguous.

Ruby-throated Hummingbird, Archilochus colubris

Uncommon but regular in very young regrowth where
flowers were available. Probably required mixed forests
in adjacent areas where sapsucker feeding holes were
available in birches and aspens.

Yellow-bellied Sapsucker, Sphyrapicus varius

Encountered rarely, usually in mixed pine/deciduous for-
est, but made at least occasional use of pine forest.
Drilled sap holes, usually in birch or aspen, but occasion-
ally also in young pines.

Downy Woodpecker, Picoides pubescens

Seen rarely, and then only in the younger mixed woods,
where some larger birch snags were available for nesting.

Hairy Woodpecker, Picoides villosus

Seen rarely and only in the younger mixed woods, where
large deciduous snags were available for nesting.

Black-backed Woodpecker, Picoides arcticus

One bird was seen foraging on several occasions in pine
forest of about 45 years of age. The absence of trees large
enough for nesting probably limited the species in most
managed forests.

Northern Flicker, Colaptes auratus

Relatively common; usually seen only in very young
regeneration (pines or mixed) where openings to the
ground were numerous. The presence of large snags is
essential to nesting.

Pileated Woodpecker, Dryocopus pileatus

Seldom ever seen passing through older forests (pine or
deciduous). There were no snags large enough for nesting
and there were few dead trees or logs and few, if any,
trees with heart rot to attract this species.

Olive-sided Flycatcher, Contopus borealis

Rare; preferred very open swampy woods, but regularly
foraged from and nested in jack pines adjacent to riparian
areas dry enough for scattered pines.

Yellow-bellied Flycatcher, Empidonax flaviventris

A characteristic species of the pine forest, rare to absent
when deciduous trees exceeded about 10 per cent of the
cover. Pines needed to be only 6 to 8 m high, but canopy
cover was always in excess of 75 per cent and trees could
be very dense. Birds were never very abundant (despite a
plethora of flies) and seemed to reach maximum density
in younger forests where branches were near the ground.
Medium to tall shrubs were almost absent in younger pine
woods occupied by this species; however, where trees
were taller and the canopy higher, shrub cover was pre-
sent and may have covered as much as 50 per cent of the
ground. Low shrubs (sheep laurel and blueberry) typically
covered almost all the ground in these pine forests,
including where this ground-nesting species took up resi-
dence.

Alder Flycatcher, Empidonax alnorum

Commonly found only in young stands where numerous
tall deciduous shrubs afforded suitable habitat. Appeared
about six or seven years after cutting or burning and was
gone by 20 to 25 years as trees matured and shaded the
ground.

Least Flycatcher, Empidonax minimus

Locally common only when trees exceeded 10 m in
height, and invariably associated with trembling aspen
and/or white birch. A few pines may have been inter-
spersed with the deciduous trees, but the species was
rarely known to nest in pines. Usually there had to be suf-
ficient deciduous tree cover for a small group of territo-
ries; a pair seldom ever occurred in isolation.

Eastern Kingbird, Tyrannus tyrannus

Rare; found where a few scattered large trees bordered
very young regeneration with open areas over which it
could forage.

Tree Swallow, Tachycineta bicolor

Foraged over any forest, but was never common because
of a scarcity of nest sites, i.e., old woodpecker cavities in
snags.

Gray Jay, Perisoreus canadensis

Seen only sporadically in pine forests and probably did
not nest there; occasionally foraged through from adja-
cent spruce swamps.

Blue Jay, Cyanocitta cristata

Uncommon; seen only in predominantly deciduous por-
tions of mixed forests, but occasionally foraged through
pines. Could have nested in any mixed forest 15 to 20
years old or older.

American Crow, Corvus brachyrhynchos

Only a few birds seen, usually near roads, railroads, or
buildings where open places afforded foraging sites.
Taller pines adjacent to openings served as nest sites for
this species.

Common Raven, Corvus corax

Commonly seen and heard near and over pine or mixed
forests; several nests found in groves of mature pines. In
forested areas, it would forage in recently cut, planted, or
burned sections and road edges.

Black-capped Chickadee, Parus atricapillus

Common in predominantly deciduous portions of mixed
forest, where it nested. Foraged in pines to some extent,
especially during the winter.

Boreal Chickadee, Parus hudsonicus

Regularly found only where jack pine was the tree cover.
Pines needed to be only 4 to 6 m high. Densities were
highest where trees were near 10 m high, and declined
somewhat as forests matured. Nest boxes were placed in
both 20- and 40-year-old stands, but only in the younger
stands were they used regularly. In each survey year only
one occupied box was ever close enough to a transect line
that census results might have been influenced by it.
Overmature forest would provide more potential nest sites
and therefore would probably have had higher densities
of this cavity nester. The species was not common, but
populations were undoubtedly somewhat higher than cen-
suses indicated as the birds became very quiet once nest-
ing was under way. Birds readily accepted nest boxes, but
squirrels interfered with most nests. In nesting areas
canopy cover was usually above 75 per cent (and often
close to 100 per cent), but well-spaced trees with closure
only somewhat above 50 per cent were occasionally cho-
sen. Tall shrubs were typically few to absent and seemed
unnecessary because birds foraged only in the pines.

Red-breasted Nuthatch, Sitta canadensis

Rare; a typically coniferous-forest inhabitant, which, like
woodpeckers, had few opportunities to nest in these man-
aged pine forests. Found as frequently in mixed forests,
probably because deciduous snags provided better nesting
opportunities for this cavity nester. Occurred once trees
reached about 6 m in height.

Brown Creeper, Certhia americana

Found with young in a nearby unmanaged patch of pines
more than 100 years old. Although it might therefore
have been expected in pine forests, none of the managed
areas censused provided nesting opportunities for this
species. Managed jack pine forests would not likely begin
to provide nesting opportunities for this species until they
were 70 to 80 years of age or older, when some larger
dead or dying trees might be expected.

Winter Wren, Troglodytes troglodytes
Rare; associated with moist depressions. Where it did
occur, the type of forest was not as important as the local
conditions. The sandy soils underlying the censused
forests generally seemed to result in conditions that were
too dry for this species.

Golden-crowned Kinglet, Regulus satrapa

Foraging readily in pine trees, but occurred only where a small
component of the forest was white spruce, which afforded
nesting sites. Deciduous trees were found in some territories,
but were unnecessary. The species appeared when trees
reached about 20 years of age, but was never numerous at any
age of forest, perhaps because spruce was never abundant.

Ruby-crowned Kinglet, Regulus calendula

Generally not a bird of pine forest, usually just wandering
in briefly to forage from adjacent spruce swamps. On rare
occasions a male or a pair remained for some time in pine
forest and some spruce trees and conceivably could have
nested, although we never had an indication that they did
so. The species seems to be dependent upon spruce for
nesting (Peck and James, 1987), and there were few
spruces to attract it to these pine plantations.

Eastern Bluebird, Sialia stalls

Seen rarely and only in recent clearcuts or bums, where it
could nest in old woodpecker holes in standing snags.
Where snags were left standing after cutting it remained
for several years as long as there was open ground where
it could forage.

Veery, Catharus fuscescens

Always occurred in mixed forests where conifers were
few to absent. Appeared when forests reached about 10
years of age and continued in relatively low numbers in
more mature forest as long as undergrowth remained lush.
Deciduous trees could be widely spaced as long as taller
shrubs were numerous.

Swainson's Thrush, Catharus ustulatus

Most numerous in mixed forest where pines dominated,
but rare in pine forest. Occurred in either situation where
tall shrubbery was present in significant amounts. Began
to appear when trees were about 10 years old and was
most abundant in 20-year-old woods. Seldom found in
taller forest where understorey was often scarce, but usual
in dense young stands where conifers and deciduous
growth were present and more equal in height. Large
areas of tall deciduous shrubs were relatively rare in the
older pine forests, so this species was seldom seen there.

Hermit Thrush, Catharus guttatus

One of the most ubiquitous and characteristic species of
pine forests and to a lesser extent of mixed woods. Moved
into an area once vegetative cover of any type reached
about 3 m high and seemed to prefer areas with a more
open character — either between dense patches of trees
and shrubs, or, preferably, where dense tree cover rose
above a cover of low shrubs, leaving fairly open space
between the low shrubs and lower tree branches.
Maximum densities for the species were reached where
pines were about 20 years of age. Numbers were lower in
more mature mixed forest, probably because deciduous
shrubs were usually numerous, but populations remained
high in maturing pine forests where tall shrubs were more
sparse.

American Robin, Tardus migratorius

Relatively rare in forested situations. Most numerous in
young plantations where there was open ground on which
to forage, and, except at the edges, virtually absent in
older forests, whether pine or mixed.

Brown Thrasher, Toxostoma rufum

Never numerous because the study forests are near the
northern edge of its range. Very young and open regener-
ation provided habitat. Associated with open shrubby
areas in either forest type.

Cedar Waxwing, Bombycilla cedrorum

Not censused well because it is a very late nester. Could
be heard flying over almost any type or age of stand, but
probably nested only in young mixed woods where
pincherry provided food.

Solitary Vireo, Vireo solitarius

Uncommon but characteristic of the jack pine forests,
only rarely wandering into adjacent mixed forest. First
began to nest when trees reached about 10 m in height,
but was most numerous in mature forests. Nested and for-
aged where canopy cover was high (more than 75 per
cent).

Philadelphia Vireo, Vireo philadelphicus

Common only in deciduous portions of older mixed forest
where trees exceeded 10 m in height. Showed a strong
preference for trembling aspen, but in rare instances white
birch formed as many as one-third of the trees in its terri-
tories.

Red-eyed Vireo, Vireo olivaceus

Always required some deciduous trees and was corrmion
in groves of pure deciduous trees; wandered on occasion
into pine forests from adjacent deciduous areas. First
occupied an area when trees reached 3 to 4 m high, but
preferred older forests.

Tennessee Warbler, Vermivora peregrina

Preferred very open edges of spruce woods. Managed
pine forests were generally too dense to attract this
species, but a few were recorded where there were open-
ings in the pines and when budworm numbers were high.

Nashville Warbler, Vermivora ruficapilla

One of the most numerous of birds in managed pine
forests and almost as numerous in mixed forests where
pines formed at least half the mix. Began to colonize an
area when trees were 5 to 6 m high and reached maxi-
mum densities where trees were 10 to 12 m tall. Trees
were relatively uniformly spaced and dense on occupied
territories; however, there was typically one opening, and

often several, where sunlight reached the forest floor and
tall shrubs grew. Where nesting occurred, the ground was
typically densely covered with sedges growing among
blueberries and sheep laurel.

Yellow Warbler, Dendroica petechia

Encountered rarely; unlikely to be found except in very
young regeneration with a high component of deciduous
growth.

Chestnut-sided Warbler, Dendroica pensylvanica

Associated with deciduous shrubs in mixed regeneration.
Appeared when growth was about 3 m high, became
abundant in growth of 6 to 7 m tall with numerous small
shrubs, and persisted in diminishing numbers until tree
crowns developed to form a canopy. Few remained once
trees reached 10 m in height in these dense plantations.

Magnolia Warbler, Dendroica magnolia

Tended to avoid pure pine forests, preferring the edges of
mixed forest, but occasionally nested in pine woods of
about 15 to 25 years of age where there were openings
and some small spruces growing. Occurred commonly in
mixed woods of 15 to 30 years old where small spruce
and balsam fir were interspersed at edges or openings.

Black-throated Blue Warbler, Dendroica caerulescens

Common only in deciduous forest taller than 16 m where
tall deciduous shrubs covered 50 to 75 per cent of the
ground. Pines were usually few to absent, but occasional-
ly were as much as 60 per cent of tree cover.

Yellow-rumped Warbler, Dendroica coronata

One of the common species in all habitats, but found in
mixed forests only where pines were dominant. Began to
colonize habitats when pines were about 5 to 6 m tall and
quickly reached maximum densities in trees of about 10
to 12 m tall. Seemed to prefer slightly open portions of
the forest but occurred almost anywhere, including some
very dense patches.

Black-throated Green Warbler, Dendroica virens

A vagrant; recorded only once.

Blackburnian Warbler, Dendroica fusca

A characteristic species of pine forest as well as of mixed
forest where pines constituted at least 40 per cent of the
tree cover. Did not begin to colonize a stand until pines
reached at least 10 m in height and was never numerous
until they exceeded 12 m. Common in the older pine
forests, usually where trees were fairly dense and uniform
and tall shrubs were few.

Palm Warbler, Dendroica palmarum

Reported to us on only one occasion in a 20-year-old pine
woods.

Bay-breasted Warbler, Dendroica castanea

Common in pine forests 40 or more years old only when
jack pine budworm was in epidemic proportions; declined
and disappeared as the budworm population crashed.
Could be found any year in adjacent mixed forest with
spruce trees, which it obviously preferred.

Black-and-white Warbler, Mniotilta varia

Found only rarely in pine forest; one pair nested in a uni-
form stand of young pines of 8 to 10 m in height where
the ground had a dense cover of blueberries and sheep
laurel, and only a relatively sparse growth of taller decid-
uous shrubs. Usually associated with the deciduous com-
ponent of mixed forests, where it was uncommon; found
in stands of about 20 years old, or at the edges of taller
woods where tall shrubs covered most of the ground,
below or among taller deciduous trees.

American Redstart, Setophaga ruticilla

Common in younger mixed woods where deciduous trees
and shrubs reached 6 to 7 m and at least some were in
fairly dense groves. Avoided older forests where trees
formed a canopy.

Ovenbird, Seiurus aurocapillus

A common and characteristic species of pine forests from
the time trees reached about 10 m in height; also present
in mixed forests once trees were 10 to 12 m high. The
main habitat requirement was a dense canopy cover in
most of the territory. Tall shrubs could cover as much as
50 per cent of the ground, but were typically sparse. The
ground was usually densely covered with low shrubs and
herbs, especially in pine forests. Herb growth in leaf litter
was the ground cover more often found in territories in
deciduous woods, but bracken would become thick later
in the season.

Connecticut Warbler, Oporornis agilis

Lone males sang for several summers in the 40- to 50-
year-old pine forest where trees were 12 to 16 m high.
The species has apparently not yet colonized this type of
habitat in any numbers in this part of the province.

Mourning Warbler, Oporornis Philadelphia

Uncommon; found where tall deciduous shrubs covered
at least 50 per cent and often nearly 100 per cent of the
ground. Usually occurred in areas cut or burned five to 10
years previously, but also at the edges of tall pine forest
where shrub growth and raspberry canes were common.

Common Yellowthroat, Geothlypis trichas

Common in regenerating areas where sedges and grasses
covered much of the ground and deciduous shrubs cov-
ered 25 to 75 per cent of the area. Gradually left an area
as trees grew and shaded the ground. Few, if any,
remained when trees were 20 years old.

Canada Warbler, Wilsonia canadensis

Rare; found in only one area of dense deciduous shrubs
with moist depressions; not specifically associated with
pines.

Scarlet Tanager, Piranga olivacea

Never numerous because it was near the northern periph-
ery of its range. Associated only with taller deciduous
trees in mixed forest.

Rose-breasted Grosbeak, Pheucticus ludovicianus

Never numerous at this latitude. Associated only with
deciduous elements of mixed forests; could be found in
more open parts of any mixed forest more than 20 years
old.

Chipping Sparrow, Spizella passerina

Uncommon; a characteristic species of pines, preferring
edges and openings only. Began to appear when trees
reached about 10 years of age and occurred in all ages
thereafter. Probably reached maximum abundance when
trees were about 20 years old and there were still numer-
ous openings to ground that was typically covered with
low shrubs.

Clay-colored Sparrow, Spizella pallida

Encountered only once and unlikely to be found in the
area, but would be associated with very open areas with
pines less than 10 years old.

Vesper Sparrow, Pooecetes gramineus

Uncommon; found where a ground cover of sedges or
grasses was present among well-spaced regenerating
pines, with few or no tall shrubs to shade the ground.
Gone by the time trees reached 10 years of age.

Song Sparrow, Melospiza melodia

Rare; not expected except at the edge of a forest, near
water, where deciduous shrubbery was present among
scattered small pines.

Lincoln's Sparrow, Melospiza lincolnii

Rare; found only in areas where pines were small and

well spaced and where sedges, grasses, and scattered

deciduous shrubs formed some ground cover. No longer

present where pines had grown beyond about 15 years of

age.

White-throated Sparrow, Zonotrichia albicollis

One of the most ubiquitous of species in both pine and
mixed forest; essentially a bird of shrub growth, whether
in early regeneration or at the edges and openings of older
forests. Would move into an area as soon as deciduous
shrubs reached about 1 m in height, provided they cov-
ered at least 50 per cent of the ground. Abundant where
pines were less than 10 years old; decreasing in numbers
in successively older stands as the canopy closed.

Dark-eyed Junco, Junco hyemalis

Common; a characteristic species of pine forests. First
occurred in pine woods when trees were 10 years of age
and was at maximum densities when trees were about 20
years of age. Avoided deciduous forest and to a lesser
extent mixed forest as well. Territories occupied forests
that were very uniform with a continuous canopy or
where only small openings and gaps were present. Tall
deciduous shrubs were sparse to absent wherever j uncos
occurred, although low shrubs were numerous as usual in
all the Gogama study forests.

Rusty Blackbird, Euphagus carolinus

Rare; wandered into young woods from adjacent wet areas.

Common Grackle, Quiscalus quiscula

Rare; wandered into young woods from adjacent wet areas.

Purple Finch, Carpodacus purpureas

Present in small numbers in every year and in most ages
and mixes of forest but never seemed to be resident there.
Although it might be expected to nest in any pines in excess
of 10 years of age, here it seemed to be just foraging.

Crossbill sp., Loxia sp.

Both Red Crossbill and White-winged Crossbill were
numerous in pine forests when jack pine budworm was
abundant, but neither remained once budworm was gone.

American Goldfinch, Carduelis tristis

Seldom ever seen in the area at any time. Visited young
mixed woods on rare occasions.

Evening Grosbeak, Coccothraustes vespertinus

Uncommon every year, but usually heard flying over-
head. Not censused well and no strong habitat affinity
was identified. Could be feeding in any pine or mixed for-
est in excess of 10 years of age, but would not likely nest
except in mature trees.

Discussion

Erskine's (1977) summary of census data relating to bird
populations in boreal forests, including jack pine habitats,
remains a very valuable contribution to the study of
northern bird communities, and is the only major work
against which our more local data set can be compared
and contrasted. Although our findings should have some
applicability to jack pine forests elsewhere in Canada, we
cannot accurately predict the situation in other distant but
similar pine forests where climatic, site, and shrubby veg-
etation conditions could be considerably different from
those of the study area in Gogama.

Erskine derived population estimates using the spot-
mapping method (International Bird Census Committee,
1970), whereas we used transect counts. The results
might therefore be expected to differ somewhat. The
accuracy of transect methods in deriving population esti-
mates has been criticized, but so has that of the best avail-
able alternative, the spot-mapping method (Svensson,
1974; Best, 1975, 1981; Oelke, 1981). While the search
continues for an accurate census method, transect counts
allow for a much more efficient sampling, and, given the
variation inherent in any sampling method (Verner,
1985), they are an appropriate means of deriving popula-
tion estimates (Emlen, 1977; Christman, 1984).

While spot-mapping calls for eight or more visits to a
plot through an entire breeding season, we attempted to
confine our counts in any one habitat to a short period of
time. This provided a "snapshot" of the species present at
one period of time and minimized a bias resulting from
birds that would inevitably wander into or out of an area
over a more prolonged period.

The short sample period we used introduces some bias
because early-nesting species (e.g.. Boreal Chickadee,
Hermit Thrush, Dark-eyed Junco, and White-throated
Sparrow) could be considerably quieter once they were
sitting on eggs, and later-nesting species (e.g.. Cedar
Waxwing) could be unsettled. However, we followed the
same procedure each year so that results would be as
comparable as possible. And given that early or late
nesters were not sampled at optimal times, our counts are
probably low. We counted birds beginning in late May, as
soon as it was apparent that even late arrivals were on ter-
ritory.

The transect method used, while it cannot adequately
sample all species, is most suited to songbirds, which
form the largest component of the forest avifauna. We
feel that no passerine was missed. Some species however,
particularly some finches (Purple Finch, crossbills, and

Evening Grosbeak), because of their habits, were not
sampled accurately, but they formed a relatively small
component of the avifauna in non-budworm years.

THE PINE FOREST

In the Gogama area, in the first few years following the
planting of jack pines, where deciduous growth (other
than low shrubs and herbaceous growth) was limited,
associated bird species were those attracted primarily by
an open habitat rather than by the pines.

Species to be expected included Red-tailed Hawk,
Northern Harrier, American Kestrel, American Crow,
Common Raven, Northern Flicker, Eastern Bluebird, and
Vesper Sparrow. A few Brown Thrasher and Ruby-
throated Hummingbird were regular; Song Sparrow and
Yellow Warbler were not expected. Northern Flicker pro-
vided cavities in adjacent snags that subsequently attract-
ed American Kestrel and Tree Swallow.

Vesper Sparrow and Eastern Bluebird can occupy such
areas for only five or six years, after sparse vegetation
becomes established but before tree growth becomes too
dense for their liking. The other species mentioned may
use such areas for as long as 10 to 15 years in gradually
diminishing numbers, as long as there are openings suffi-
cient for foraging.

The most abundant species, the White-throated
Sparrow, is among the first to colonize once ground cover
becomes well established and trees exceed about 1 m in
height. It is also the only species that persists through all
ages of the maturing forest wherever edges and openings
are found.

When pines reached 10 to 15 years of age, most of the
species that formed the core of the pine forest communi-
ty— Yellow-bellied Flycatcher, Boreal Chickadee, Hermit
Thrush, Nashville Warbler, Yellow-rumped Warbler,
Ovenbird, Chipping Sparrow, and Dark-eyed Junco — had
moved in and established themselves. All of these species
reached their highest densities in forests of about 20 to 25
years of age. Spruce Grouse had also become established
at a high density (Szuba and Bendell, 1983). These
species all persisted as forests matured, so that even at 20
years of age the pine forest had almost the full comple-
ment of species that would remain as the forest matured.

Three additional species of importance were Solitary
Vireo, Blackburnian Warbler, and, where some spruces
were present. Golden-crowned Kinglet. These began to
appear only when trees were about 20 years old and
reached maximum numbers by the time the forest was 40
years old.

Northern Goshawk was hunting in forests by the time
trees were 20 years of age (radio-tagged grouse were
taken), and would remain as forests matured. Sharp-
shinned Hawk was seen and certainly would also be hunt-

ing for small birds in wooded areas of between 20 to 60
years of age. When budworm numbers were high,
Tennessee Warbler and crossbills were attracted to forests
of more than 20 years of age. Bay-breasted Warbler
occurred in very high numbers during the peak of a bud-
worm outbreak, but only in forests of about 40 or more
years old. Evening Grosbeak and to a lesser extent Purple
Finch fairly regularly also frequented pine forests of any
age above 20 years, but seemed to make somewhat limit-
ed use of the pines, except when budworm was abundant.

Several other species that we know have nested, or
that easily could nest, in pine woods and are likely to do
so on occasion include Brown Creeper, Red-breasted
Nuthatch, Swainson's Thrush, American Robin, Ruby-
crowned Kinglet, Magnolia Warbler, Black-and-white
Warbler, and Connecticut Warbler. Of these, only Red-
breasted Nuthatch, Brown Creeper, and Connecticut
Warbler are likely to make extensive use specifically of
pine forests in this district. The nuthatch and creeper,
however, are limited by nest-site availability, and the
warbler is at the edge of its range here and still rare.

Any of the other species that were found in pine
forests more than 20 years old (Alder Flycatcher, Gray
Jay, Blue Jay, Black-capped Chickadee, Veery, Cedar
Waxwing, Red-eyed Vireo, Chestnut-sided Warbler,
Palm Warbler, American Redstart, Common Yellow-
throat, and Lincoln's Sparrow) tended only to be wander-
ing through or making very limited use of pines, or were
attracted by vegetation other than pines.

Several differences are notable between our counts in
managed forests (greater than 20 years of age) and those
presented by Erskine (1977). Erskine considered Ruby-
crowned Kinglet as a characteristic species, while we sel-
dom ever encountered it. Differences probably in canopy
cover and certainly in tree-species composition would
account for the conflicting results. Canopy cover aver-
aged only 20 to 30 per cent on the stands Erskine studied,
while our stands had in excess of 60 per cent canopy
cover. The spruce swamps found in wetter areas adjacent
to some of the pine forests in our area were the usual
haunts of Ruby-crowned Kinglet and had more open
canopies than the pines. Ruby-crowned Kinglet seems
heavily reliant on spruces (Peck and James, 1987; person-
al experience), and where this species occurred in the
pine forests, some spruce trees were usually present.
Erskine also considered Swainson's Thrush, American
Robin, and Tennessee Warbler to be frequent inhabitants
of jack pine, whereas we found them scarce to absent.
The reason for this difference might be the more open
nature (and associated tall shrub growth) of the stands
considered by Erskine (1977).

Erskine (1977) considered only five species as found
in most jack pine stands (Hermit Thrush, Ruby-crowned
Kinglet, Yellow-rumped Warbler, Dark-eyed Junco, and

White-throated Sparrow). We found eight more species
virtually always present and forming an important com-
ponent of the avifauna in managed pine forests: Spruce
Grouse, Yellow-bellied Flycatcher, Boreal Chickadee,
Solitary Vireo, Nashville Warbler, Blackburnian Warbler,
Ovenbird, and Chipping Sparrow. Although Solitary
Vireo, Nashville Warbler, and Chipping Sparrow were
mentioned as frequent by Erskine, others were not specif-
ically mentioned, and Blackburnian Warbler was not even
listed as occurring in jack pine forests.

Spruce Grouse is not censused well by spot-mapping
or transect counts and therefore did not register more than
present in either study, but other work in the Gogama area
clearly showed this species to be numerous in jack pines
(Szuba and Bendell, 1983). It may just have been over-
looked in censuses done elsewhere, but in more open pine
forests it may well have been scarce to absent.

The increased canopy cover of the managed forests
would certainly be more attractive to Yellow-bellied
Flycatcher, Boreal Chickadee, Solitary Vireo, Ovenbird,
and probably also Nashville Warbler and Blackburnian
Warbler. Although there have been few censuses in jack
pine stands in boreal and near-boreal areas of eastern
North America, the recorded absence of Blackburnian
Warbler in such stands (Erskine, 1977) was surprising
compared to the numbers we found. Erskine' s censuses in
the Quebec Clay Belt (Erskine, 1970) and near Matheson,
Ontario (Erskine, 1971), were at a somewhat more
northerly latitude than our study area (48° 26' and 48° 32'
N vs. 47° 28' N), but they were not beyond the range of
Blackburnian Warbler (Cadman, Eagles, and Helleiner,
1987). Blackburnian Warbler has been recorded in jack
pine stands somewhat farther south and less boreal (48°
08' N) in northern Minnesota (Niemi, 1974). While this
species has been linked with fir, hemlock, and other types
of pine forest, it must also be considered a dominant
member of at least denser stands of jack pine in southern
boreal areas of central Ontario. We found Blackburnian

Warbler consistently, even in the absence of budworm, in
our area.

The overall density figures that we recorded in man-
aged jack pine forests (even after budworm was no longer
attracting large numbers of Bay-breasted Warbler) were
about double the density reported by Erskine (1977) in
jack pines. Also, despite some differences in census tech-
niques, which could result in somewhat higher totals by
our method, several species in the managed forests appear
to occur in notably higher numbers than reported in jack
pine by Erskine (1977; see Table 10). Our mean density
figures for Hermit Thrush are two to three times higher,
and for Yellow-rumped Warbler three to four times high-
er. Even more remarkable are Nashville Warbler and
Yellow-bellied Flycatcher, more than 10 times higher,
and Ovenbird, more than 16 times higher, than densities
given by Erskine (1977). Boreal Chickadee also appeared
much more numerous (and consistent) than recorded by
Erskine, but was still at relatively low numbers. Our cen-
sus totals in managed jack pines are similar to those given
by Erskine (1977) for typical boreal spruce forest.

Such differences are no doubt accounted for in part by
the increased tree density (and uniformity) of the forests
we studied, which provided increased canopy cover and
higher foliage volume. The number of trees per hectare
and the basal area values for five stands given by Erskine
(1977) are about half of those in P-2 and P-3 at Gogama,
resulting in our higher canopy-cover values. In the
Gogama forests the layer of low shrubs covering virtually
100 per cent of the ground is probably also important.
Erskine (1977) had ground covers of only 40 to 50 per
cent in the Clay Belt areas. The low shrubs in the
Gogama forests would be particularly attractive to Hermit
Thrush, Nashville Warbler, and Ovenbird. The increased
numbers of these three species, plus the presence of
Blackburnian Warbler, would easily account for the dif-
ferences between our results and the estimates provided
by Erskine (1977).

Table 10. Comparison of mean density values (males or pairs/km^) for
selected jack pine-inhabiting bird species in the area studied by Erskine
(1977) and areas P-2 and P-3 of the present study.

Erskine (1977)

P-2

P-3

Yellow-bellied Flycatcher

Hermit Thrush

Nashville Warbler

Yellow-rumped Warbler

Ovenbird

THE MIXED PINE/DECIDUOUS FOREST

Recently cut or burned areas that, although planted with
pines, would produce nearly equal numbers of deciduous
trees and numerous deciduous shrubs, attracted the same
bird species as areas newly planted to pines. However,
birds had fewer years to use the new mixed area before
shrub growth rendered it largely unsuitable for these
open-country species.

Within five years shrub growth and ground cover pro-
vided for two principal species, Common Yellowthroat
and White-throated Sparrow, and for fewer numbers of
Lincoln's Sparrow and Mourning Warbler (Table 5).
Alder Flycatcher also was beginning to become very
numerous in the shrub growth. By this time open-country
species were virtually gone.

Between five and 10 years, as vegetation reached
above 3 m in height and became more dense, many more
species began to appear (Ruffed Grouse, Blue Jay, Veery,
Hermit Thrush, American Robin, Cedar Waxwing, Red-
eyed Vireo, Nashville Warbler, Chestnut-sided Warbler,
Yellow-rumped Warbler, and Dark-eyed Junco).
Additional species appeared between 10 and 20 years
(including Yellow-bellied Flycatcher, Black-capped
Chickadee, Swainson's Thrush, Magnolia Warbler,
Black-and-white Warbler. American Redstart, Rose-
breasted Grosbeak, and Chipping Sparrow), and those
that were so abundant at 10 years of age were largely
gone. Most of the species that colonized between 10 and
20 years of age would also remain as the forest matured.

Half of the species were attracted to the dense growth
of deciduous shrubs and young deciduous trees, and most
of the rest used both pines and deciduous growth. The
species with the highest densities were those using specif-
ically deciduous growth (Alder Flycatcher, Veery, Red-
eyed Vireo, Chestnut-sided Warbler, Black-and-white
Warbler, American Redstart, and Rose-breasted
Grosbeak) or those that reach highest densities where
deciduous growth occurs with pines (American Robin,
Magnolia Warbler, and White-throated Sparrow). The
combination of species attracted by tall shrubs as well as
those attracted by mixed tree growth produced the highest
density figures recorded for any habitat.

Meanwhile, many of the species that occurred in pure
pines were present in mixed habitats, but some were well
below levels recorded in pines (Yellow-bellied
Flycatcher, Yellow-rumped Warbler, Chipping Sparrow,
and Dark-eyed Junco; Tables 3 and 7) while others were
no more abundant (Hermit Thrush and Nashville
Warbler), indicating that mixed forest was not as
favourable a habitat for most of them.

By the time a mixed habitat reached 40 years of age
many of the early-successional shrub dwellers had depart-
ed (Alder Flycatcher, Chestnut-sided Warbler, American
Redstart, Mourning Warbler, Common Yellowthroat, and

Lincoln's Sparrow) or were present only in low numbers
(Black-and-white Warbler, Magnolia Warbler, and
Swainson's Thrush). Meanwhile, a new suite of species
had taken up residence. These were associated with
deciduous trees (Least Flycatcher, Philadelphia Vireo,
and Scarlet Tanager) or with deciduous shrubs below a
tree canopy (Black-throated Blue Warbler), or were those
appearing in medium-aged or older pine forests
(Blackburnian Warbler, and, in low numbers. Golden-
crowned Kinglet and Solitary Vireo).

The absence of numbers of shrub dwellers in medium-
aged mixed forests dramatically lowered the species
totals. The addition of some more deciduous-inhabiting
species did not compensate for the departure of the early-
successional species. In addition, some of those species
associated specifically with pines had declined much far-
ther (Hermit Thrush, Nashville Warbler, and Yellow-
rumped Warbler), or had been virtually eliminated (Dark-
eyed Junco and Chipping Sparrow). Thus, the mixed for-
est, while attracting a somewhat higher diversity of
species than the pine forest because of the combination of
deciduous and coniferous components, had bird densities
that were only comparable to those of the pine forest
(Tables 5 and 9). The increased diversity did not result in
increased density.

PINE FOREST VS. MIXED FOREST

Recently planted and regenerating areas were likely to be
visited by similar suites of bird species, regardless of the
forest cover in later years. The main difference between
pine and mixed forest was that, where mixed growth
dominated, the very early-successional bird species had
fewer years to take advantage of the open spaces between
trees.

In young woods of about 20 years of age, however,
notable differences were apparent between plantations
composed almost entirely of jack pine and areas where
pines were mixed among deciduous trees and shrubs. If
we exclude the casually occurring species, 20-year-old
pine stands regularly had 10 to 12 species, nine or 10 of
which made up the bulk of the population, whereas simi-
larly aged mixed woods normally had 20 or 21 species,
13 to 15 of which made up the bulk of the population.
Pines hosted Spruce Grouse and Boreal Chickadee,
whereas mixed stands had Ruffed Grouse and Black-
capped Chickadee. In pines. Alder Flycatcher, Veery,
Swainson's Thrush, Red-eyed Vireo, Blue Jay, Chestnut-
sided Warbler, American Robin, Magnolia Warbler,
Black-and-white Warbler, and American Redstart were
few to absent, but these were numerous in mixed stands.
Conversely. Yellow-bellied Flycatcher, Ovenbird. Dark-
eyed Junco. and Chipping Sparrow were numerous in
pines but much rarer in mixed areas. Nashville Warbler,

Yellow-rumped Warbler, and White-throated Sparrow
occurred in nearly equal numbers in either habitat. The
mixed areas hosted about twice the number of species as
well as twice the density of birds as the young pine
woods.

In medium-aged forests the differences between pine
and mixed remained pronounced, although a number of
different species were involved. The pines hosted Spruce
Grouse, Boreal Chickadee, Yellow-bellied Flycatcher,
Hermit Thrush, and Solitary Vireo, while mixed areas had
Ruffed Grouse, Black-capped Chickadee, Least
Flycatcher, Veery, Swainson's Thrush, Red-eyed Vireo,
and Philadelphia Vireo. The pines also had Yellow-
rumped Warbler, Nashville Warbler, Chipping Sparrow,
Dark-eyed Junco, and White-throated Sparrow, while the
mixed forests usually had few or none of these. And the
mixed areas had Black-throated Blue Warbler, Scarlet
Tanager, Black-and-white Warbler, Rose-breasted
Grosbeak, and Magnolia Warbler, whereas the pines usu-
ally had none of these species. Common to both types of
forest and in similar numbers were only two species,
Blackbumian Warbler and Ovenbird.

In medium-aged forests pine regularly hosted 13 to 16
species (slightly more than at 20 years of age) with eight
to 10 of these forming the bulk of the population, and
mixed regularly hosted 17 to 22 species, with only six to
nine of them forming the bulk of the population.
Populations in pure pine and mixed were about equal,
although the mixed forests had a greater diversity of
species. But the species complement of the two areas was
very different. Unless both types of habitat were present,
many species could not find appropriate nesting habitat.

Notable in both types of actively managed forest was
the relative absence of cavity-nesting species. This can be
attributed largely to the absence of snags (flattened before
planting) and larger older trees that in a natural forest
might be dead or dying and thus suitable for excavation
by cavity nesters.

few years for several species, which showed large
declines: Bay-breasted Warbler and Yellow-rumped
Warbler from 1985 to 1986, and Ovenbird and Nashville
Warbler from 1986 to 1987. However, those declines
were not sustained in subsequent years. The previous
larger numbers were likely due to the increased presence
of budworm, either attracting nesting pairs or possibly
increasing the numbers of offspring present in a subse-
quent year. From 1987 to 1992 no species showed an
obvious downward trend. There is some evidence of a
downward trend for Chipping Sparrow from 1987 to
1992, but this could still be due to successional change. A
longer-term data set would be better able to distinguish
population trends from short-term fluctuations.

When the pine forest reached 40 to 50 years of age
average numbers appeared to decline only slightly from
those in 20-year-old forest. In 1985 the population in P-3
was high (624 pr/km-) because of an outbreak of bud-
worm, and declined markedly over the next two years. In
the last six years of censusing, the population fluctuated
around 300 pr/km^ (mean 316 pr/km-^) It seems that a
population slightly in excess of 300 pr/km^ would likely
be maintained until the forest becomes mature to overma-
ture, at which time openings and dying trees would prob-
ably attract more species and possibly increase population
levels somewhat.

Bird populations in areas of mixed growth no doubt
have a higher complement of species sooner than pure
pines because of shrub growth. In a six-year-old mixed
area numbers of birds equalled or exceeded those of a 20-
year-old pine plantation. In the mixed woods, numbers
climbed until reaching more than 1000 pr/km^ by 20
years of age. From 20 to 40 years of age the numbers for
mixed woods declined again and appeared to be about the
same as pine forests at 40 years of age. Those levels were
likely to be maintained until forests matured when popu-
lation levels might increase slightly again.

POPULATION CHANGES

Very young pine stands had comparatively few birds
(about 140 pr/km^ in P-I). Numbers increased to some-
what in excess of 300 pr/knr by the time stands were 20
years old and showed no apparent change from that over
the seven years of the study, although there was consider-
able fluctuation (mean 335 pr/km- in P-2).

In stands younger than about 40 years of age, changes
in the numbers of any species over several years were
likely to be the result of successional changes in the habi-
tat. In the older forests, however, changes might indicate
a changing abundance as a result of some other factor. In
the medium-aged pine forest (P-3; Table 5) with the
longest data set, there were notable changes in the first

FORESTRY

The diet of insectivorous birds may be more than 80 per
cent destructive forest insects (Takekawa, Garton, and
Langelier, 1982). It has been proven that birds signifi-
cantly reduce the numbers of insects in forests (Holmes,
Schultz, and Nothnagle, 1979; Mattson et al, 1968;
Takekawa, Garton, and Langelier, 1982). Birds may not
be able to exert much influence in controlling some
insects such as budworm once it has reached epidemic
proportions, but they may do a great deal to keep insects
at endemic levels (Kendeigh, 1947; Otvos, 1979; Thomas
et al., 1979; Takekawa, Garton, and Langelier, 1982). It
would seem, then, to be in the best interests of forestry to
do whatever is possible through forestry practices to
encourage birds to use the planted forests and to maintain

population levels at least as high as those found in natu-
rally occurring forests.

The relatively uniformly aged and dispersed jack pine
forests that result from planting following clearcutting are
obviously relatively good environments for certain
species of birds, and several species occur in densities as
high or higher than recorded elsewhere in boreal jack pine
forests or even boreal spruce forest. However, the number
of species able to make extensive use of pure jack pine
plantations is somewhat limited. Especially at younger
ages, the mixed woods attract many more and different
species (although they also include at least a few of the
pine forest inhabitants). The mixed forests (or predomi-
nantly deciduous forests) provide an essential habitat for
some species that do not occur in pine forests. The lack of
deciduous vegetation in managed pine forests (through
herbicide treatment) is particularly critical in the five to
20 years following planting. Many early-successional bird
species rely on deciduous growth. Populations of these
species also tend to be high in the few years available
through the total rotation time of the forest.

The uniform nature of the managed pine forests also
tends to limit certain species. Golden-crowned Kinglet,
for example, occurs only where some spruce has regener-
ated among the pines. This branch-tip forager could be
very important in budworm suppression, and its popula-
tion could be considerably enhanced through the inclu-
sion of a small percentage of spruce in a planting. Spruce
Grouse is also frequently encountered where spruce
occurs within pine forest. Spruce provides the grouse as
well as other species with much better winter cover.

Species that like a dispersion of small openings in the
canopy of the forest (Ruby-crowned Kinglet and
Chipping Sparrow) are also no doubt less populous than

they might be if forests were less uniform. However, nei-
ther is rare in any event.

Perhaps the one forestry practice that has the most
severe impact is the knocking down of snags before plant-
ing. It is known that nest-site scarcity can limit hole-nest-
ing birds (Dickson, Conner, and Williamson, 1983;
Zarnowitz and Manuwal, 1985). Woodpeckers were
encountered regularly only in M-2, the young mixed
woods, where a number of birch snags had been left
standing. With the exception of chickadees, which were
rather rare although regular, primary cavity nesters were
virtually absent in medium-aged pine forests. Without the
primary excavators, secondary cavity users were also
almost totally absent, as were creepers. The cavity nesters
are, in large part, year-round residents and could have a
significant impact on insect populations through the peri-
od of the year when insects are inactive or present in rela-
tively small numbers.

The short rotation time in intensively managed forests
also eliminates Pileated Woodpecker, which requires
trees in excess of 55 cm DBH to meet its preferred nest-
ing requirements (Conner, 1979) and numerous snags to
supply its food needs. Intensively managed patches of
forest provide almost no place for any cavity nester.

Leaving snags and a few scattered live trees (especial-
ly deciduous) standing, and providing a small proportion
of deciduous trees within pine forests for future snags
would help to encourage the cavity nesters. In addition to
snags, the dying deciduous trees would create some open-
ings. These would attract other insectivorous species,
such as Nashville Warbler, Chipping Sparrow, and
White-throated Sparrow, which would further enhance
insect suppression.

Conclusions

Managed uniform-aged jack pine forests in the Gogama
area included the following:

1. Good breeding habitat for eight to 11 bird species
(Spruce Grouse, Yellow-bellied Flycatcher, Hermit
Thrush, Nashville Warbler, Yellow-rumped Warbler,
Ovenbird, Chipping Sparrow, Dark-eyed Junco, plus
Golden-crowned Kinglet, Solitary Vireo, and
Blackbumian Warbler as forests mature)

2. High numbers of five passerine species (Yellow-bel-
lied Flycatcher, Hermit Thrush, Nashville Warbler,
Yellow-rumped Warbler, and Ovenbird)

3. Casual and intermittent habitat for an additional 12 to
18 species

4. Large numbers of Bay-breasted Warbler and substan-
tial numbers of Evening Grosbeak and crossbill
species during budworm outbreaks

5. Population densities of birds comparable to those nor-
mally found in boreal spruce forests (200 to 400 pr/km^)

6. Low numbers of only one cavity-nesting species
(Boreal Chickadee)

Uniform-aged mixed forests in the Gogama area included
the following:

1. When young (about 20 years old), twice the number of
species (20 to 21) and population densities two to three
times higher than those found in pine forests of similar
age

2. When older, slightly higher numbers of species (13 to
16) than, but densities only about equal to, those found
in similarly aged pines

3. Casual or intermittent habitat for an additional 12 to 16
species

4. Habitat attractive to many species not found at all in
pine forests, and only low numbers of most species
that typically form the core population in pine forests

5. When younger, habitat usable by many early-succes-
sional species that may not occupy young pine woods

6. Low numbers of only one cavity-nesting species
(Black-capped Chickadee), except where snags were
left standing

Pine forests, before they reached 20 years of age, had
already attracted most of the species that would form the
bulk of the bird population at any age thereafter. Mixed
forests had a more noticeable and continuous change in
species composition until the forest was close to 40 years
of age.

Cavity-nesting species were scarce in either type of
forest. Providing even 5 per cent deciduous trees in pine
forests and/or leaving 2 to 5 per cent deciduous trees
standing during harvest would ensure nesting sites for
cavity nesters, thereby increasing their populations.

There were no apparent trends in overall populations
of birds over the eight-year period of the study in medi-
um-aged pine forest.

Acknowledgements

Fieldwork was supported by the Royal Ontario Museum. tions; and the Ontario Ministry of Natural Resources for

We thank the E. B. Eddy Company for allowing us to providing Forest Resource Inventory maps and allowing

undertake these studies in forests planted and managed by us to occupy a temporary campsite on Makwa Lake. We

them; Dr. J. F. Bendell for his assistance and encourage- are most appreciative of comments made by Dr. D. A.

ment during the study; G. B. Murphy for assistance in the Welsh and Dr. A. J. Erskine on an earlier draft of this

field; K. Szuba and B. Naylor for observations and assis- manuscript, and of the assistance of Cathy Ay ley in man-

tance in the field; the photography department of the uscript preparation.
Royal Ontario Museum for preparation of the illustra-

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ROYAL ONTARIO MUSEUM LIFE SCIENCES CONTRIBUTIONS

Life Sciences Contributions are a numbered series

149 Occurrence of the Cladid Inadunate Crinoid

of scientific publications of varied subject matter.

Thalamocrinus in the Silurian (Wenlockian) of

Most recent contributions include the following:

New York and Ontario

George C. Mcintosh and Carlton E. Brett

157 Classification and Evolution of the Oraseminae

1988,20 pp., ill., $7.75

in the Old World, Including Revisions of Two

ISBN 0-88854-342-5

Closely Related Genera of Eucharitinae

(Hymenoptera: Eucharitidae)

148 Shallow-Water Hydroids of Bermuda:

John Michael Hemty

The Athecatae

1994, 184 pp., ill., $24.95

Dale R. Calder

ISBN 0-88854-41 2-X

1988, 112 pp., ill., $24.50

ISBN 0-88854-339-5

156 Conodonts of the Lower Border Group and

Equivalent Strata (Lower Carboniferous) in

147 Biostratigraphy and Palaeontology of the

Northern Cumbria and the Scottish Borders, U.K.

ScoUard Formation, Late Cretaceous and

Mark A. Pumell

Paleocene of Alberta

1992, 80 pp., ill., $19.95

Loris S. Russell

ISBN 0-88854-405-7

1987, 23 pp., ill., $7.00

ISBN 0-88854-338-7

155 Revision of the World Species of

Spalangiopelta (Hymenoptera: Chalcidoidea:

146 Stipatocrinus, a New and Unusual Camerate

Pteromalidae: Ceinae)

Crinoid from the Lower Silurian of Western

D. Christopher Darling

New York

1991,48 pp., ill., $11.00

James D. Eckert and Carlton E. Brett

ISBN 0-88854-395-6

1987, 17 pp., ill., $6.00

ISBN 0-88854-336-0

154 Shallow-Water Hydroids of Bermuda:

The Thecatae, Exclusive of Plumularioidea

145 An Annotated Checklist of the Fishes of the

Dale R. Calder

Chagos Archipelago, Central Indian Ocean

1991, 144 pp., ill., $24.50

Richard Winterbottom, Alan R. Emery, and

ISBN 0-88854-354-9

Erling Holm

1987, 240 pp., ill, $50.00

153 Silurian Trilobites from the Northern Yukon

ISBN 0-88854-329-8

Territory

Rolf Ludvigsen and Ronald P. Tripp

144 Revision of the Caddisfly Genus Psilotreta

1990, 64 pp., ill., $12.95

(Trichoptera: Odontoceridae)

ISBN 0-88854-349-2

Charles R. Parker and Glenn B. Wiggins

1987, 55 pp., ill.. $12.00

152 The Type Species of the Ordovician Trilobite

ISBN 0-88854-332-8

Genus Isotelus: I. gigas Dekay, 1 824

David M. Rudkin and Ronald P. Tripp

143 Phylogeny, Speciation, and Palaeoecology of

1989, 24 pp., ill., $10.25

the Early Carboniferous (Mississippian)

ISBN 0-88854-345-X

Conodont Genus Mestognathus

Peter H. von Bitter, Charles A. Sandberg, and

151 The Structure of the Call Note System of

Michael J. Orchard

the WarblingVireo

1986, 115 pp., ill., $25.00

Daryl Howes-Jones and Jon C. Barlow

ISBN 0-88854-319-0

1988,40 pp., ill., $11.00

ISBN 0-88854-343-3

A catalogue of ROM publications in print is

available from

150 Late Cretaceous-Early Tertiary

Dinoflagellates and Acritarchs from the Kashi
Area, Tarim Basin, Xinjiang Province, China
Mao Shaozhi and Geoffrey Norris

University of Toronto Press
10 St. Mary Street, Suite 700
Toronto, Ontario M4Y 2W8
Canada

1988, 100 pp., ill., $25.00
ISBN 0-88854-334-4

Tel. (416) 978-2229 Fax (416) 978-4738

ISBN 0-88854-4 1 3-8 ISSN 0384-8 1 59

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