Grassland and Shrubland Birds
within the Carden Plain:
Recent Monitoring Results
1
Grassland and Shrubland Birds within the Carden Plain:
Recent Monitoring Results
Compiled by Ron Reid
January 2011
Summary of Conclusions:
1. Birds of the Carden Plain are not exempt from the documented regional declines in
grassland species, with average annual declines of 2% to 4% over the past decade,
even though habitat conditions and extent do not appear to have changed
significantly.
2. Open grassland habitats support the highest density of target bird species, and have
maintained the highest frequency of area-sensitive species.
3. Changes in abundance of individual species show a pronounced trend towards losses
of short-grass specialists such as Horned Lark, and increases in a small group of
shrubland species, notably Song Sparrow and Eastern Towhee.
4. Diversity of shrubland species is showing a strong decline, at the same time as the
abundance of two shrubland species is increasing rapidly.
5. Annual monitoring shows declines for 9 grassland species and 5 of 7 shrubland
species, but with considerable unexplained variation between Cameron Ranch and
Windmill Ranch plots.
6. Habitat patches in Ramara Township consistently rank lower in target bird diversity
and density than the Carden IBA plots to the east, with that pattern especially
pronounced for Upland Sandpiper and Eastern Meadowlark, both area-sensitive
species.
7. The most significant grassland areas identified in Ramara are clustered southeast of
Brechin and north of the Trent-Severn Canal.
8. The extensive grasslands of the CKL South section (north half of former Eldon
Township) stand out as particularly diverse and productive in their bird life.
2
Acknowledgements
Major parts of this manuscript have been summarized from data analysis and internal reports
prepared by Kristen Field and Kyra Howes of The Couchiching Conservancy. Financial support
has been provided by the Ontario Species at Risk Stewardship Fund, Environment Canada
Habitat Stewardship Program, and the George Cedric Metcalf Charitable Foundation.
Data collection for these projects would not have been possible without the dedication of
dozens of volunteers from Ontario Field Ornithologists, Toronto Ornithological Club, Carden
Field Naturalists, and Couchiching Conservancy. Their assistance is greatly appreciated.
The Couchiching Conservancy is a non-profit, charitable land trust whose mission is to protect
the special natural features of the Couchiching region for future generations.
The Ontario Species at Risk Stewardship Fund supports greater public involvement in all kinds of
species at risk protection and recovery activities. The fund provides $18 million to eligible
projects over four years (2007 – 2011). The purpose of the fund is to inspire and encourage
people to become involved in species at risk recovery, and build on the good work already done
by groups and individuals.
The Government of Canada Habitat Stewardship Program for Species at Risk. Funds from this
program promote the participation of local communities to help with the recovery of species at
risk and prevent other species from becoming a conservation concern.
3
Background
The Carden Plain lies northeast of Lake Simcoe on an area of shallow limestone bedrock
(Chapman and Putnam, 1984). Some sections of this landform have developed alvar habitats
characterized by extremely thin soils and distinctive ecological communities. Other extensive
areas were cleared in the late 1800s for cattle ranching, and have been maintained in this use as
rough pasture set between linear wooded wetlands.
The shallow droughty soils in this area have prevented conversion to agricultural cropland, with
the exception of a few scattered hayfields. These conditions, together with frequent wildfires
until the late 1940s, have also limited the growth of large woody species, although the amount
of low shrubland has increased in recent decades. Therefore, the Carden Plain retains a
significant amount of natural grassland habitat, and is a haven for relatively large populations of
grassland birds.
The Carden limestone plain has been recognized for several decades as an exceptional breeding
habitat for grassland and shrubland birds. In 1998, Birdlife International recognized most of
former Carden Township and parts of the adjacent townships of Eldon, Bexley, and Ramara as
an Important Bird Area (IBA) of national significance (Coxon and Reid 2001). In 2008, the
Couchiching Conservancy and partner groups published an Integrated Carden Conservation
Strategy which addressed the balance among conservation, quarry, and community values in
this area (Couchiching Conservancy, 2008).
A more detailed analysis of conservation values, published in 2009 as the Carden Conservation
Plan Working Draft, recognized that the Carden limestone plain extends westward well into
Ramara Township (Eco Source Management 2009). The Plan identified three sections within the
Carden Plain – North Kawartha Lakes portion (from the Trent-Severn Waterway northwards),
South Kawartha Lakes portion (primarily in former Eldon township), and the Ramara portion
(see Figure 1).
The Conservation Plan noted that “there is relatively little background information available for
the Ramara section, and further background and baseline studies need to be conducted there”.
Grassland birds are rapidly declining throughout North America over the past several decades
(Cadman et. al. 2007; Sauer et al. 2005). Indeed, Bird Studies Canada has concluded that
“grassland birds in North America have experienced the most pronounced declines of any group
of birds on the continent, and the declines appear to be continuing unabated.” (McCracken,
2005; BSC, 2009).
Among 37 species of grassland birds monitored by the Breeding Bird Survey, 32 are showing
some form of decline, while only 5 are increasing (Sauer et al. 2005). The most pronounced
declines are taking place in the north-eastern sections of the range of grassland birds on the
continent (Jon McCrackin, pers. comm.)
4
Table 1: High-priority grassland bird species in southern Ontario,
with Breeding Bird Survey population trends 1968 – 2007.
(Bird Studies Canada 2009)
1. E = endangered SC = Special Concern
Southern Ontario is an important area for grassland birds because of their relatively high
representation in this area. In fact, it has been recognized as the “largest and most important
area of grassland in the Northeast” by the Partners in Flight program (Pashley et. al., 2000). For
example, Bird Studies Canada notes that Ontario “supports one-fifth of the World’s population
of Bobolinks” (Heagy and McCracken, 2004).
Considerable conservation effort has been undertaken on the Carden Plain since 2001, both to
acquire significant habitats and to encourage good stewardship of landscapes of conservation
interest. During the same period, additional properties have been acquired by the aggregate
industry, with several major new sites licensed as future quarries. However, to date there has
been very little obvious change in actual land uses or habitat conditions, with the exception of a
few small sites that have been excluded from this study.
5
6
Sources of Monitoring Data
A. IBA monitoring comparison
In the year 2000, a monitoring program based on standardized point counts was carried out to
identify high priority grassland and shrubland habitats within the Carden Plain IBA. Each
relatively homogenous area of habitat was delineated and given a “Habitat Patch” number.
Permanent monitoring plots for each Habitat Patch were set by recording the UTM coordinates;
most of the sites fell along accessible roadsides. Each Patch was assigned to a habitat type and
the size of each Habitat Patch was estimated.
A second round of monitoring using the same protocols and sites was carried out in 2008 to
provide comparable data. This comparison, based within a relatively stable landscape, was
intended to assess whether the continent-wide declines in grassland birds would also be evident
at a local scale. Shrubland birds were also included in the monitoring, in part because grassland
and low shrubland habitats often intergrade in Carden, and in part to provide a point of
comparison with another guild of birds. Other habitats, such as forests and wetlands, were not
monitored.
The following 30 bird species were identified as target species for field monitoring because of
their importance as grassland/shrubland species:
American Goldfinch
American Kestral
Black-billed Cuckoo
Bobolink
Brown Thrasher
Chestnut-sided Warbler
Clay-coloured Sparrow
Common Nighthawk
Eastern Bluebird
Eastern Kingbird
Eastern Meadowlark
Eastern Towhee
Field Sparrow
Golden-winged Warbler
Grasshopper Sparrow
Gray Catbird
Horned Lark
Indigo Bunting
Loggerhead Shrike
Northern Flicker
Northern Harrier
Northern Mockingbird
Red-headed Woodpecker
Red-tailed Hawk
Savannah Sparrow
Short-eared Owl
Song Sparrow
Upland Sandpiper
Vesper Sparrow
Whip-poor-will
On the Carden Plain, some species require relatively large grassland or shrubland habitats for
nesting. Because of their sensitivity to changes in habitat amounts, these species require special
consideration in conservation efforts. The term “area-sensitive” describes a species whose
presence or absence is closely related to the amount of breeding habitat area within a given
spatial unit (Couturier, 1999). Among the selected IBA target species, the following 11 have
been identified as being area-sensitive:
Bobolink
Eastern Bluebird
Eastern Meadowlark
Grasshopper Sparrow
Horned Lark
Loggerhead Shrike
Northern Harrier
Red-tailed Hawk
Savannah Sparrow
Short-eared Owl
Upland Sandpiper
7
The selection of monitoring sites was structured to represent distinct habitat patches: areas of
land differentiated by changes in habitat and cultural boundaries. A total of 93 habitat patches
were sampled in both the 2000 and 2008 studies. As shown on Figure 2, these represent five
different habitat types, including seven areas of Limestone Pavement, 49 Open Grassland, 20
Treed Grassland, 15 Shrubland and two Cropland habitat types.
1.
Class I habitats, or limestone pavement, are characterized by patches of bare bedrock,
often very dry in summer, with sparse vegetation. These habitats are infrequent and
occur largely in the northern sections of the IBA. On these barren habitats, the most
frequent species encountered include Savannah Sparrow, Eastern Meadowlark, Upland
Sandpiper, and Horned Lark. These habitats are likely also important for nesting
Common Nighthawk and Whip-poor-will along their edges. Vegetation characteristic of
this habitat type include lichens, algae, mosses, Stonecrop, Early Saxifrage, Silvery
Cinquefoil, Field Chickweed, and Stitchwort. Sixteen out of thirty IBA target species were
found in Class I habitat, which comprised 610 hectares of the total IBA.
2.
Class II habitats, or open grasslands, are much more abundant, and are characterized by
moderately dense grasses and other forbs, with only a few scattered trees or shrubs.
Most of these grasslands are pastured by cattle. Savannah Sparrow, Bobolink, Eastern
Meadowlark and Upland Sandpiper are the most common birds in this habitat type, and
it also supports the highest density of the less common Grasshopper Sparrow.
Vegetation characteristic to this habitat type include Prairie Smoke, Harebell, Hairy
Beardtongue, Mullein, and Hawthorn shrubs. Twenty-four target species were found in
Class II habitat, which comprised 6530 hectares of the total IBA.
3.
Class III habitats, or treed grasslands, are also generally pastured, but include more than
25% cover of trees and tall shrubs. Again, Savannah Sparrow and Eastern Meadowlark
are the most frequently encountered species, with other common birds including
American Goldfinch, Brown Thrasher, and Field Sparrow. The highest density of
Loggerhead Shrike occurrences are also in this class. Characteristic vegetation includes a
high ratio of grasses, clover and vetches, with smaller patches of wildflowers, and
woody shrubs and small trees such as Fragrant Sumac, White Elm, White Birch, and
Hawthorn. Twenty-two target species were found in Class III habitat, which comprised
1560 hectares of the total IBA.
4.
Class IV habitats, or shrublands, are distinctly different, with relatively dense shrub
cover amid a patchwork of grasslands and scattered trees. These habitats are often
transitional, occurring on abandoned pasture lands, but they may also persist for long
periods. Several different types are present, including those dominated by Hawthorns,
Fragrant sumac, and Common juniper. The most common shrubland birds are Brown
Thrasher, American Goldfinch, and Song Sparrow, but this habitat also supports the
highest densities of such species as Eastern Towhee, Indigo Bunting, Clay-colored
Sparrow, Vesper Sparrow, Gray Catbird, and Golden-winged Warbler. Vegetation
characteristic of shrublands include Spreading Juniper, Fragrant and Staghorn Sumac,
Gray Dogwood, Hawthorn, and Downy Arrowwood. Twenty-four target species were
found in Class IV habitat, which comprised 3350 hectares of the total IBA.
8
Class V habitats, or croplands, include hayfields and more intensively managed
rotational pasturelands, with dense uniform grass cover. Relatively few of these
habitats were surveyed, but these areas appear to be particularly attractive to Bobolink
and Eastern Meadowlark, with Eastern Kingbird also frequently occurring along field
edges. While the density of birds in these productive areas is relatively high, only a few
of the target species nest in this habitat type. Nine of thirty target species were found in
Class V habitat, which comprised 2615 hectares of the IBA.
5.
During both the 2000 and 2008 breeding bird seasons, each monitoring plot was surveyed for
the presence of birds at least twice. All counts were complete between May 31 and June 15,
and between 5:00 and 11:00 in the morning. The semi-circular plots had a radius of one
hundred meters delineated by estimation, giving each plot a sample size of 1.57 hectares. The
number and species of birds seen or heard within the semi-circle during a 5-minute period were
counted.
In the 2000 survey, all field work was completed by a contractor, Terry Bradt, who visited many
sites multiple times. In 2008, the task of counting the birds was given to teams of expert
volunteers from the Ontario Field Ornithologists. Each volunteer team surveyed a group of
approximately ten sites, with two five-minute counts carried out, separated by a two-minute
quiet period.
Synopsis of results:
Because the original worksheets from the year 2000 monitoring had been misplaced, only a
partial comparison of data was possible. In addition, because population levels may vary in
response to short-term factors such as weather conditions, a comparison of only two points in
time has to be treated with caution. Despite these limitations, several clear trends can be
determined from the data comparison:

Significant declines in the diversity of the 30 target species continue to occur at a rate of
2% - 4% per year, with shrubland birds showing the greatest decline (see Table 2).

Open grassland habitats show the highest density of target bird populations in 2008,
followed by tree grassland habitats (see Table 3).

Area-sensitive species now occur much more frequently in open grassland habitats than
other habitat types (see Table 4).

Changes in abundance of individual species show a pronounced trend towards losses of
short-grass specialists such as Horned Lark, and increases in a small group of shrubland
species, notably Song Sparrow and Eastern Towhee (see Figure 3).
9
Figure 2: Habitat Distribution in the Carden Plain IBA
igure 1: Classified alvar, grassland, and shrubland habitat within the Carden Plain IBA
10
Table 2: Change in Average Number of Target Species per Point Count between 2000 and 2008
Habitat Type
# of Point
Year 2000 Year 2008
Trend
Counts
Limestone pavement
7
5.0
4.8
0.4%/year decline
Open grassland
44
6.8
5.6
2.2%/year decline
Treed grassland
19
7.6
6.2
2.2%/year decline
Shrubland
12
7.5
4.8
4.4% per year decline
Table 3: Comparison of Density (Total # of Target Birds per Point Count) in 2008
Habitat Type
# of Point
Year 2000 Year 2008
Counts
Limestone pavement
7
n/a
4.7
Open grassland
44
n/a
9.4
Treed grassland
19
n/a
6.8
Shrubland
12
n/a
5.0
Table 4: Comparison of Occurrence of Area-Sensitive Species in 2000 and 2008
Habitat Type
# of Point
Year 2000 Year 2008
Counts
Limestone pavement
7
2.3
1.9
Open grassland
44
3.1
3.4
Treed grassland
19
3.1
2.3
Shrubland
12
3.1
1.4
Figure 3: Changes in Species Abundance
Change in average number of individuals observed in 86 sample plots
between 2000 and 2008
250%
200%
150%
100%
50%
0%
-50%
-100%
-150%
HOLA AMKE UPSA EABL YSFL FISP VESP SASP GRSP BOBO EAME EAKI AMGO BRTH SOSP EATO
change in 2008 -88% -84% -33% -15% -100% -7%
-66%
-9%
105% 40%
48%
34%
8%
36%
231% 162%
species
11
B. Cameron Ranch and Windmill Ranch Annual Monitoring
As a baseline for long-term monitoring of bird populations, a series of 16 permanent monitoring plots
were established on Cameron Ranch in 2005, and an additional 13 plots established on Windmill Ranch
in 2007. Each plot has a 100 metre radius. These two ranches are slated to be regulated as the Carden
Alvar Provincial Park. They are both grazed by cattle, and this activity is intended to continue as a
management tool for bird habitats.
Figure 4: Monitoring plots on Cameron Ranch
12
Figure 5: Windmill Ranch Monitoring Stations
Each spring during late May and June, volunteers from the Ontario Field Ornithologists and the Toronto
Ornithological Club have completed two five-minute point counts at each monitoring station. A
summary of monitoring results for the first five years has been compiled by the Couchiching
Conservancy (Howes 2009).
13
Monitoring results:
Based on the monitoring results to date, a total of 15 grassland and shrubland species were assessed,
although three of these species (Horned Lark, Eastern Bluebird, and Golden-winged Warbler) were not
present on both properties. While the length of the monitoring period is not sufficient to establish longterm trend lines, several observations raise interesting points for further study:


The overall diversity of birds seen during monitoring visits is declining – from 85 species in 2006
to 74 species in 2007, 71 species in 2008, and 63 species in 2009.
Among the 15 species assessed, the numbers of individuals observed appears to be declining for
9 species (60%)on Cameron Ranch, and 5 species (33%) on Windmill Ranch, with a few other
species showing increases (see Table 4).
Table 5: Short-term population trends in assessed species
Species
Cameron Ranch
Upland Sandpiper
Increasing
Bobolink
Stable
Eastern Meadowlark
Slightly increasing
Horned Lark
Decreasing
Eastern Loggerhead Shrike
Decreasing
Grasshopper Sparrow
Increasing
Vesper Sparrow
Increasing?
Savannah Sparrow
Increasing?
Northern Harrier
Sparse
Henslow’s Sparrow
No data
Short-eared Owl
No data
Eastern Bluebird
No data
Brown Thrasher
Slightly decreasing
Eastern Towhee
Increasing
Golden-winged Warbler
No data
Clay-colored Sparrow
Increasing
Black-billed Cuckoo
Increasing
Grey Catbird
Decreasing
Brown-headed Cowbird
Decreasing
Windmill Ranch
Decreasing
Decreasing?
Decreasing
Sparse
Decreasing
Increasing
Decreasing
Strongly decreasing
Sparse
Occasionally present but sparse
No data
Strongly decreasing
Slightly decreasing
Decreasing
Decreasing
Stable
Sparse
Strongly decreasing
Strongly decreasing
Perhaps the most surprising aspects of these results are:
 the frequent disparity in trends observed between the two ranches,
 the 5 out of 7 shrubland species found to be declining on Windmill Ranch,
 the increasing frequency of Grasshopper Sparrows.
Ongoing monitoring will continue to help identify the factors at work influencing these trends.
14
C. Monitoring Plots in Ramara Township
In response to recommendations in the Carden Conservation Plan, a volunteer-based survey of
grassland birds within the Ramara section of the Carden Plain was carried out in the spring of 2010. In
advance of the survey, habitat patches were mapped using the same criteria as in the year 2000 and
2008 Carden IBA programs. No limestone pavement sites were mapped in Ramara, but the project
mapped 26 open grassland, 7 treed grassland, 7 shrubland, and 19 cropland (hay and managed pasture)
sites.
A point count monitoring plot was selected to represent each habitat patch, with the plots clustered in
eight areas as shown in Figure 6. Volunteers carried out two point counts at each plot, using a
monitoring protocol identical to that used in the Carden IBA. The intent of this project was to assess
how grassland and shrubland habitats in Ramara compare to their counterparts just to the east.
Figure 6: Location of monitoring plots in Ramara
15
Monitoring results:
A compilation of monitoring results from the 59 Ramara monitoring plots is shown in the tables below,
together with a comparison of equivalent results from the CKL North and CKL South sections of the
Carden Plain (Figure 1).
Table 6: Comparison of Average Number of Target Species per Point Count
Habitat Type
Ramara
CKL North CKL South
Cropland (Hay)
3.0
n/a
n/a
Open grassland
3.8
6.8
5.5
Treed grassland
4.0
5.2
8.8
Shrubland
3.3
4.8
n/a
Table 7: Comparison of Density (Total # of Target Birds per Point Count)
Habitat Type
Ramara
CKL North CKL South
Cropland (Hay)
3.5
n/a
n/a
Open grassland
4.2
9.3
9.6
Treed grassland
3.9
5.8
9.8
Shrubland
3.4
5.0
n/a
Table 8: Comparison of Occurrence of Area-Sensitive Species (# per point count)
Habitat Type
Ramara
CKL North CKL South
Cropland (Hay)
1.4
n/a
n/a
Open grassland
2.2
3.3
4.1
Treed grassland
1.1
2.1
2.8
Shrubland
0.4
1.4
n/a
As Tables 6-8 illustrate, habitat patches in Ramara consistently rank lower than either CKL North or CKL
South in all of the habitat classes, and in comparisons of the number of species present, their density,
and the number of area-sensitive species observed.
The reasons for this disparity are not entirely clear. One factor which may be significant is the generally
smaller size of habitat patches in Ramara, and the frequent presence of wooded fencerows that cause
greater fragmentation, especially of open grasslands. Habitats in Ramara also appear to be more
scattered, with longer stretches of woodland or agricultural croplands between patches, compared to
the CKL sites. It is also possible that habitats in Ramara are more intensively managed for farming,
although this requires further study.
A more detailed comparison of area-sensitive grassland birds:
Five species of grassland birds which occur widely on the Carden Plain exhibit characteristics of areasensitivity i.e. they require relatively large patches of grassland habitat to successfully breed. As shown
in Figure 7, Ramara hayfields, and to a lesser extent Ramara grasslands, are consistently less welcoming
for area-sensitive species. This pattern is especially pronounced for Upland Sandpiper and Eastern
Meadowlark. The other conclusion to be drawn from this graph is the importance of the extensive
grasslands of north Eldon Township (CKL South) to this group of bird species.
16
Figure 7: Comparison of Area-sensitive Grassland Species
Occurrence of Area-Sensitive Grassland Species as a Percentage
of Sites Surveyed
Eastern Meadowlark
Bobolink
Ramara Hay
Grasshopper Sparrow
Ramara Grassland
Savannah Sparrow
CKL South
CKL North
Upland Sandpiper
0
20
40
60
80
100
% of point counts
Upland Sandpiper
Savannah Sparrow
Grasshopper Sparrow
Bobolink
Eastern Meadowlark
CKL North
52%
61%
32%
70%
85%
CKL South
70%
100%
40%
80%
100%
Ramara
Grassland
11%
69%
11%
76%
53%
Ramara
Hay
0
63%
5%
57%
15%
Significant Grassland Areas in Ramara:
As a final factor in comparing Ramara grasslands to those in the Carden IBA, individual habitat patches
were assessed against a modified set of significance criteria developed through the Carden IBA
Conservation Action Plan (Coxon and Reid 2001). As a threshold of significance, these criteria identify as
significant any habitat patch with a point count plot containing:
 7 or more target species
 5 or more area-sensitive species, or
 15 or more birds among all target species combined.
No patches of Ramara shrubland or cropland meet these criteria, but a single patch of treed grassland
(MA0606) and three patches of grassland (MA 0104, MA0207, DA0108) do qualify. The latter site is
actually located in former Dalton Township north of Lake Dalrymple, and the treed grassland site is just
east of the southern end of the lake in the Lakeview Beach area. The other two grassland sites are
located south and east of the Lafarge quarry south of Brechin, as shown on Figure 8. These sites are
close to other significant grassland areas just to the east that were identified as significant during the
earlier Carden IBA surveys. Similarly, areas of limestone pavement and grassland on both sides of
Simcoe Rd. 47 along Ramara’s eastern boundary had been previously assessed as significant.
17
Figure 8: Grassland Habitat Patches South of Brechin
Note that habitat patches MA0104 and MA0207 ranked as significant grasslands, comparable to areas
along Concession 1 just to the east which were included in earlier Carden IBA monitoring.
18
Conclusions
1. Birds of the Carden Plain are not exempt from the documented regional declines in grassland
species, with average annual declines of 2% to 4% over the past decade, even though habitat
conditions and extent do not appear to have changed significantly.
2. Open grassland habitats support the highest density of target bird species, and have
maintained the highest frequency of area-sensitive species.
3. Changes in abundance of individual species show a pronounced trend towards losses of
short-grass specialists such as Horned Lark, and increases in a small group of shrubland
species, notably Song Sparrow and Eastern Towhee.
4. Diversity of shrubland species is showing a strong decline, at the same time as the
abundance of two shrubland species is increasing rapidly.
5. Annual monitoring shows declines for 9 grassland species and 5 of 7 shrubland species, but
with considerable unexplained variation between Cameron Ranch and Windmill Ranch plots.
6. Habitat patches in Ramara Township consistently rank lower in target bird diversity and
density than the Carden IBA plots to the east, with that pattern especially pronounced for
Upland Sandpiper and Eastern Meadowlark, both area-sensitive species.
7. The most significant grassland areas identified in Ramara are clustered southeast of Brechin
and north of the Trent-Severn Canal.
8. The extensive grasslands of the CKL South section (north half of former Eldon Township)
stand out as particularly diverse and productive in their bird life.
19
Literature Cited
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Chapman, L.J. and D.F. Putnam. 1984. The Physiography of Southern Ontario. Ontario Ministry of
Natural Resources, Toronto.
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Coxon, A. and R. Reid. 2001. Carden Plain Important Bird Area: Conservation Action Plan. The Carden
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Heagy, Audrey E. and J.D. McCracken. 2004. Monitoring the State of Ontario Migratory Land Birds. Bird
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Howes, Kyra. 2009. Upland Birds of Carden Plain: Species Summary and Habitat Recommendations for
Grassland Management. The Couchiching Conservancy, Orillia. 70 pp.
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20