3.0 STUDY AREA SETTING

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1 Peel-Caledon Significant Woodlands and Significant Wildlife Habitat Study Final Report - June STUDY AREA SETTING 3.1 Region of Peel Physical Characteristics The Region is divided into six physiographic regions by Chapman and Putnam (1984) that reflect major divisions in surficial landform, glacial history, soils, drainage and climate (Figure 3). These can have a bearing on woodland composition as well as the types and distribution of wildlife habitat. All of the Iroquois Plain and the majority of the Peel Plain, and a portion of the South Slope physiographic regions are within the Cities of Mississauga and Brampton. The Town of Caledon contains the north section of the South Slope as well as portions of the Niagara Escarpment, Oak Ridges Moraine, a narrow strip of Peel Plain and in the extreme northwest, the Guelph Drumlin Field and a small portion of the Hillsburgh Sandhills. The Region of Peel is unusual in that it contains portions of five major watersheds. These are administered by the Credit Valley Conservation (CVC), Toronto Region Conservation Authority (TRCA), Conservation Halton (CH), Nottawasaga Valley Conservation Authority (NVCA) and Lake Simcoe Region Conservation Authority (LSRCA). The approximate watershed boundaries are shown in Figure 4. For this study, CVC and TRCA have been the most involved of the various conservation authorities, in terms of provision of data and comments, because their jurisdictions together cover most of the Region. Woodlands The Region of Peel was primarily a forested landscape prior to European settlement, consisting of both upland and wetland (swamp) treed areas. The present day vegetation suggest there may have been scattered prairie and savannah remnants in the south, mainly in the Clarkson and Lorne Park areas, and there would have been some open marsh areas along Lake Ontario and elsewhere, but outside of this, the natural vegetation was likely forest or swamp. Rowe (1972) identifies two forest sections within two forest regions in the Region of Peel: 1) the Niagara Section of the Deciduous Forest Region, and 2) the Huron-Ontario Section of the Great Lakes-St. Lawrence Forest Region. The boundary between these approximates the southern edges of the ORM and the Niagara Escarpment. The Deciduous Forest Region is a northerly extension of the broad-leaved forests that dominate the northeastern United States. The Niagara Section approximates the area known as the Carolinian Zone (sensu Fox and Soper ) in southern Ontario, although the northern limits of this are generally slightly south of the northern limits of the Niagara Section as mapped by Rowe (1972). For the purpose of this report, the main distinction between these regions/sections is that there are a few tree species with generally southern distributions, such as black walnut, sycamore, swamp white oak, white oak and shagbark hickory, which are less common or absent in the more northerly Huron- Ontario forest section. North-South Environmental Inc. page 29 Dougan & Associates Sorensen Gravely Lowes

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7 Peel-Caledon Significant Woodlands and Significant Wildlife Habitat Study Final Report - June 2009 However, Rowe s classification describes broad differences across Canada and the distinction between these two forest regions and sections within Peel Region is not very pronounced. The ecological characteristics of the Niagara Escarpment, notably the thin soils and imperfect drainage, and the Oak Ridges Moraine, principally the better drained morainal deposits, likely override the broader differences used by Rowe to delineate his forest regions and sections. The majority of woodlands in the Region south of the Niagara Escarpment were cleared for agriculture and the many settlements that were founded during the early to mid-1800s. Agriculture continued as the principal land use until the more rapid urbanization of the southern half of the Region, which commenced in the 1940s and has resulted in a further loss and fragmentation of woodlands and other natural areas. The Region Official Plan (ROP) identifies an Urban System and a Rural System within Peel (Figure 5). The Urban System is composed of lands within the 2031 Regional Urban Boundary, which include lands in the Cities of Brampton and Mississauga, as shown on Schedule D of the ROP. For the purpose of this study, the consideration of criteria and thresholds specific to the Urban System will include lands within the 2031 Urban Boundary. The Rural System within Peel includes lands outside of the 2031 Urban Boundary, which entirely encompasses the Town of Caledon. For the purpose of this current study, criteria and thresholds specific to the Rural System will only be applied to the Town of Caledon. Within the Rural System are the Rural Service Centres of Bolton, Caledon East and Mayfield West, which serve as the primary foci for growth within the Rural System, and the Rural Settlements including the villages and hamlets. At present, the Cities of Mississauga and Brampton are essentially completely urban, and the Town of Caledon is mainly rural, and also contains the majority of the remaining natural cover in the Region. This has been an important consideration in the development of appropriate thresholds for a number of criteria for both significant woodlands and significant wildlife habitat. For example, the higher forest cover in rural Caledon and the occurrence of more large patches of woodland (especially above the Niagara Escarpment) means that the threshold for the size of a significant woodland in this area will be higher than in the urban areas to the south. It is worth noting that in some rural areas where agricultural practice has declined, the area of forest cover has increased since the early 1900s. The approximate present day distribution of forest patches in the Region of Peel is shown on Figure 6. It should be noted that Figure 6 is based on the best available mapping sources (see Section 2.1.2) but owing to the limitations of aerial photography and ongoing changes in the landscape (succession and development), there may be some small woodlands that are incorrectly shown. The Figure is provided only to illustrate the general extent of woodlands in the Region of Peel and the Town of Caledon. The forest cover statistics (Table 1) strongly reflect the current development patterns, with the Cities of Brampton and Mississauga having forest cover of 7.3% and 6.7% respectively, and the Town of Caledon with 31.5%. As a result, the two Cities have a relatively small proportion of the Regional forest cover, contributing 7.5% and 7.6% each while Caledon accounts for 84.9% of the Regional forest cover. The overall number of patches is substantially higher in Caledon (624) as is the mean patch size (35.2 ha) when compared to either Brampton or Mississauga. North-South Environmental Inc. page 35 Dougan & Associates Sorensen Gravely Lowes

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13 Peel-Caledon Significant Woodlands and Significant Wildlife Habitat Study Final Report - June 2009 With a population projected to grow to 1,640,000 by 2031, per the Places to Grow (OMPIR 2006), it is important to protect and enhance the urban forest within Peel Region before it is incrementally lost. Protecting and enhancing the urban forest has been identified in cities worldwide as one method of addressing sustainability objectives related to stormwater, air quality and climate change mitigation. The urban tree canopy reduces the heat island effect in urban areas, improves air quality and intercepts rainfall before it becomes stormwater runoff. It also provides habitat for resident and migratory flora and fauna. These functions contribute to a healthy natural heritage system in Peel. Table 1: Forest cover for municipalities in the Region of Peel (all woodlands > 0.5 ha) Municipality Forest Cover in each Municipality ha (%) Contribution to Regional Forest Cover (%) No. of Forest Patches Mean Patch Size Peel 25,867 (20.6%) 100% 1,127* 23.0 Caledon 21,954 (31.5%) 84.9% Brampton 1,972 (7.3%) 7.6% Mississauga 1,940 (6.7%) 7.5% * Note that for woodlands that straddle municipal boundaries, portions of the same woodland will be counted in each municipality. Thus the sum of the number of patches for the three municipalities will not add up to the number of patches for the entire Region. The definition of woodlands recommended by this study (Appendix 1) excludes woodlands smaller than 0.5 ha. The number of woodlands smaller than 0.5 ha can only be approximated since recent updates on the woodland data layer only included woodlands > 0.5 ha. However, as can be seen in Table 2, such patches constitute a very small proportion of the overall forest area. For example, in all of Peel Region, approximately 7.6% of the forest patches are smaller than 0.5 ha, but this constitutes only 0.21% of the total forest cover. The municipality in which these small woodlands constitute the largest proportion of the forest patches is the Town of Caledon (8.9%), however, this represents far less than a quarter of one percent of the total forest cover in the Town (0.19%). Thus, exclusion of woodlands smaller than 0.5 ha has little affect on forest cover statistics (this does not necessarily mean their protection on a site specific basis is unimportant). Table 2: Approximate area and number of forests patches smaller than 0.5 ha for municipalities in the Region of Peel Municipality No. of patches % of No. of forest Area of patches < Proportion of area of < 0.5 ha patches < 0.5 ha 0.5 ha forest patches <0.5ha Peel % % Caledon % % Brampton % % Mississauga 8 2.0% % Table 3 provides a breakdown of forest patches in different size classes. Not surprisingly, a large number of forest patches in the Region and each of the municipalities are relatively small (<10 North-South Environmental Inc. page 41 Dougan & Associates Sorensen Gravely Lowes

14 Size (ha) Peel-Caledon Significant Woodlands and Significant Wildlife Habitat Study Final Report - June 2009 ha). The proportion of total forest cover for Brampton and Mississauga that is composed of woodlands under 10 ha is substantially greater (22.4% and 26.6% respectively), than for Caledon (5.9%) or the Region (9.5%). This suggests that smaller (<10ha) forests in Brampton and Mississauga may be more important than small woodlands in Caledon, since they represent a substantially greater proportion of the total forest cover in the urban municipalities. Even woodlands as small as 2 ha represent a larger proportion of the forests in Brampton (4.8%) and Mississauga (6.0%), as compared with Caledon where they constitute only 1.4% of all forest cover. Table 3 also illustrates the scarcity of large woodlands (>30 ha) in the two southern municipalities. Brampton and Mississauga respectively have 13 and 12 forest patches greater than 30 ha in size, whereas there are 48 in the Town of Caledon. Table 3: Number and area of forest in different size classes (all woodlands > 0.5 ha) Peel Region Caledon Brampton Mississauga No. patches Forest area (ha) % of total forest area No. patches Forest area (ha) % of total forest area No. patches Forest area (ha) % of total forest area No. patches Forest area (ha) % % % % % of total forest area % % % % , % % % % subtotal 903 2, % 461 1, % % % % % % % % % % % % % % % > , % 48 20, % 13 1, % % totals 1,126 25, % , % 251 2, % 263 2, % Note : The entire area of forest patches that straddled municipal boundaries was included in each municipality, therefore the totals for each municipality do not match with Table 1. For the true forest cover in each municipality, use data from Table 1. Wildlife As noted above, Peel Region was primarily a forested landscape prior to European settlement. Consequently, the assemblage of wildlife species present at the time was a reflection of a forested environment. Although differences in the types of tree species present in the two Forest Regions almost certainly influenced the types of wildlife species present, there was probably considerable overlap in terms of species occurrence. Some wildlife species that inhabited the pre-settlement landscape are no longer present or occur very rarely. Large mammals such as black bear, cougar, occasionally moose, bobcat and lynx were likely inhabitants of these areas. Most of these larger mammals no longer occur in the Region owing to their intolerance of humans and changes in land cover, although there have North-South Environmental Inc. page 42 Dougan & Associates Sorensen Gravely Lowes

15 Peel-Caledon Significant Woodlands and Significant Wildlife Habitat Study Final Report - June 2009 been sightings of black bear in the Caledon area in recent years as well as the possible sightings of cougar ( As for breeding birds, forest species, especially forest interior species (i.e., those found 100 m or more away from the forest edge) were likely quite common. Representative examples of forest species that would have been encountered include Wild Turkey, Blue-gray Gnatcatcher, Wood Thrush, Cerulean Warbler and Ovenbird in the southern parts of Peel, and Black-throated Blue Warbler, Yellow-rumped Warbler, Blackthroated Green Warbler, Black-and-White Warbler and Northern Waterthrush in the northern parts. The significant forest clearing that has taken place across the Region of Peel since that time has resulted in a dramatic shift in species composition. Forest dependent species have become far less common, especially in the urbanized southern half of the Region. Open-country species have correspondingly increased in abundance during this time. Examples of open-country breeding bird species include American Kestrel, Horned Lark, Barn Swallow, Eastern Kingbird, Savannah Sparrow, Bobolink and Eastern Meadowlark. The reduced forest (and reduced forest interior), wetland and riparian cover that currently exists favours common wildlife species such as raccoons, skunks and deer, and significantly limits the opportunities for more sensitive habitat specialists such as amphibians and forest interior or other area-sensitive songbirds. However, a number of wildlife species of conservation concern and with somewhat specialized habitat requirements still persist in the Region s fragmented landscape. Examples include Black-crowned Night-Heron, Bank Swallow, Ring-necked Snake, Blue-spotted Salamander, Northern Saw-whet Owl and River Otter. On the whole, wildlife species of conservation concern occur throughout the Region, although there are few in urbanized areas. Some of the open-country species listed above also utilize the active and abandoned agricultural fields in the landscape. There are also still sizeable patches of forest with forest interior in the Town of Caledon (see Table 4) that continue to provide habitat for a variety of provincially, regionally and locally significant wildlife species. Table 4: Number and area of forest interior* in different size classes Peel Caledon Brampton Mississauga Area of Area of Area of Area of No. No. No. interior interior interior interior patches patches patches (ha) (ha) (ha) (ha) 4 ha or more of interior forest 10 ha or more of interior forest No. patches 5, , , , * Forest interior is defined as the area within each forest patch that is greater than 100 m from an edge. North-South Environmental Inc. page 43 Dougan & Associates Sorensen Gravely Lowes

16 Peel-Caledon Significant Woodlands and Significant Wildlife Habitat Study Final Report - June Town of Caledon Physical Characteristics The Town of Caledon contains four of the six physiographic regions in the Region of Peel. The South Slope occupies the southern portion of the Town, extending from the boundary with the City of Brampton along Mayfield Road, to the Niagara Escarpment and Oak Ridges Moraine. The Oak Ridges Moraine is a provincially significant landform that extends from the Town of Caledon approximately 300 km east to the Ganaraska forest in Northhumberland County. Likewise the Niagara Escarpment is another provincially significant landform that extends from the Canadian border with the United States at the Niagara River, north to Tobermory. The Guelph Drumlin Field extends into the Town from the west, and a very small portion of the Hillsburgh Sandhills occurs in the extreme northwest corner of the Town. A very narrow sliver of the Peel Plain occurs along the north side of Mayfield Road in the vicinity of Bolton. Unlike the rest of Peel Region where urban development has masked much of the influence of physiography, the characteristics of the predominantly rural landscape in Caledon reflect the physiographic regions. Agriculture is still a dominant land use on the South Slope, whereas the conditions above the Niagara Escarpment, and to some extent on the Oak Ridge Moraine, are less conducive to farming, primarily due to soil type. Four of the five watersheds in the Region occur in the Town of Caledon; the areas under the jurisdiction of the TRCA and CVC cover the majority of the Town and the watershed of the NVCA and LSRCA occupy very small areas in the extreme northeastern corner of the Town. Woodlands The current forest cover in the Town reflects the physiographic regions 3. The South Slope has a relatively low proportion of forest cover (10.6%) compared with the areas above the Escarpment and on the Oak Ridges Moraine (42.0% and 42.3 %) (Table 5). Also, the mean size of patches is much smaller on the South Slope (10.0 ha) compared to the area above the Escarpment (55.1 ha) or on the Oak Ridges Moraine (40.0 ha), reflecting the increased fragmentation typical of areas dominated by agricultural land use. It is interesting to note that 97.4% of the forest cover in Caledon is within the Greenbelt (including the NEC and ORM). Wildlife Natural cover in the Town of Caledon is significantly higher than in the Cities of Brampton, Mississauga or the Region overall. As a result, the wildlife community present also tends to be more diverse and abundant. Larger forested blocks provides habitat for greater numbers of forest species, particularly those known to be area-sensitive. For example, only 74 forest patches still remain in Brampton and Mississauga combined, which contain forest interior and are potentially large enough to support area-sensitive forest breeding bird species (i.e., measured at 100 m from the forest edge). If they do exist, such species are usually present in very low numbers and are at threat of displacement as a result of changing surrounding land uses. In contrast, the Town of Caledon has 283 forest patches large enough to support area-sensitive forest breeding bird 3 The boundaries used to determine statistics are based on the plan boundaries for the Niagara Escarpment and Oak Ridges Moraine, which differ from the true physiographic regions as mapped in Chapman and Putnam (1984). The Hillsburgh Sandhills are combined with the Niagara Escarpment owing to the extremely small area it occupies. North-South Environmental Inc. page 44 Dougan & Associates Sorensen Gravely Lowes

17 Peel-Caledon Significant Woodlands and Significant Wildlife Habitat Study Final Report - June 2009 species. Also, while only 2 patches of forest interior (i.e., defined by forest greater than 100 m for the forest edge) exceeded 25 ha in Brampton and Mississauga, 71 patches exceeded this threshold in the Town of Caledon. The local amount and distribution of forest patches in the Town of Caledon are also such that even the smaller forest patches, by virtue of their association with larger forest patches, tend to support a richer assemblage of breeding bird species. Connectivity of natural features is also enhanced compared to Brampton and Mississauga as a result of the rural as opposed to urban land use that prevails, making the landscape easier to move across for a variety of wildlife species. Table 5: Forest cover within different physiographic units 4 and plan areas (woodlands >0.5ha) within the Town of Caledon Physiographic Unit or Plan Area Total area (ha) of physiographic unit or plan area Forest cover (ha and %) within physiographic unit or plan area % of total forest cover No. of patches Mean patch size (ha) Town of Caledon 69,599 21,954 (31.5%) 100% Oak Ridges Moraine (ORM) 15,866 6,713 (42.3%) Niagara Escarpment Plan 13,743 7,060 (51.4%) (NEP) Area Area including and above NEP Area 30,419 12,779 (42.0%) South Slope 23,314 2,462 (10.6%) Greenbelt (including ORM 55,824 21,383 (38.3%) and NEP Area) Area outside of Provincial Plans 13, (4.2%) Overview of Natural Heritage Features and Designated Areas Table 6 summarizes some of the natural heritage features and designations in Peel Region and the Town of Caledon, which are discussed briefly below. Both the Region and Town fall within OMNR s Ecological Site Regions 6E and 7E. An Ecological Site Region is not a policy designation, rather, it refers to an ecological subdivision of the land based upon a combination of climate, physiography and biological productivity. The original Site Regions of Ontario were developed and mapped by Angus Hills (Hills 1961), and were later modified based on more detailed mapping and interpolation of physiographic features (Jalava et al. 1996). These have been further subdivided into Ecodistricts by the OMNR, as described in the Great Lakes Conservation Blueprint for Terrestrial Biodiversity (Henson and Brodribb 2005). The OMNR is in the process of refining technical papers for significant wildlife North-South Environmental Inc. page 45 Dougan & Associates Sorensen Gravely Lowes

18 Peel-Caledon Significant Woodlands and Significant Wildlife Habitat Study Final Report - June 2009 Table 6: Summary of natural heritage features, areas, regions and policy designations in the Region of Peel and the Town of Caledon 4. REGION OF PEEL TOWN OF CALEDON Ecological Site Regions (OMNR) 6E & 7E 6E & 7E Significant Vegetation Communities - PROVINCIAL: 8 - PROVINCIAL: 8 Significant Plant Species on Record Significant Wildlife Species on Record (excluding fish) - NATIONAL (COSEWIC): 2 - PROVINCIAL (COSSARO): 2 - PROVINCIAL (OMNR-NHIC): 20 - NATIONAL (COSEWIC): 11 - PROVINCIAL (COSSARO): 11 - PROVINCIAL (OMNR-NHIC): 27 - NATIONAL (COSEWIC): 2 - PROVINCIAL (COSSARO): 2 - PROVINCIAL (OMNR-NHIC): 4 - NATIONAL (COSEWIC): 4 - PROVINCIAL (COSSARO): 4 - PROVINCIAL (OMNR-NHIC): 6 Total Species at Risk on Record (including fish) 304 records 104 records Size (hectares) 125,400 ha 69,599 ha Region of Peel Greenlands System 24,423 ha (19.47% of Peel) 21,679 ha (31% of Caledon) Policy Areas 1. Niagara Escarpment Plan 2. Oak Ridges Moraine Conservation Pan 3. Greenbelt Plan 5 Designated Areas 1. Areas of Natural and Scientific Interest (ANSIs) (OMNR) 2. Provincially Significant Wetlands (PSWs) 3. Environmentally Sensitive Areas (ESAs - Peel) Non-Provincially Significant Wetlands 1. Locally Significant Wetlands 2. Unevaluated Wetlands 1. 13,743 ha (11% of Peel) 2. 15,866 ha (13% of Peel) 3. 55,824 ha (45% of Peel) 5 1. Life Science: 6419 ha Earth Science: 3517 ha ha (2.2% of Peel) ha (7.5% of Peel) 2471 ha (2% of Peel) ha (0.4% of Peel) ha (1.6% of Peel) 1. 13,743 ha (20% of Caledon) 2. 15,866 ha (23% of Caledon) 3. 55,824 ha (80% of Caledon) 5 1. Life Science: 5809 ha Earth Science: 3678 ha ha (0.4% of Caledon) ha (12% of Caledon) 2376 ha (3.4% of Caledon) ha (0.7% of Caledon) ha (2.7% of Caledon) 4 DATA SOURCES: All significant species and vegetation community data were provided by the NHIC, March All area calculations were derived from GIS layers and data provided by the Region of Peel Planning Department, March 2008, and have been rounded up the nearest hectare. 5 Note that the NEP and ORM are part of the Greenbelt, thus the areas provided for the first two are included within the areas provided for the Greenbelt. North-South Environmental Inc. page 46 Dougan & Associates Sorensen Gravely Lowes

19 Peel-Caledon Significant Woodlands and Significant Wildlife Habitat Study Final Report - June 2009 habitat that pertain specifically to Site Regions 6E and 7E, and the two Ecodistricts which cover the majority of the Region of Peel (i.e., 6E-7 and 7E-4) have both target ecological communities and species of conservation concern identified (see Henson and Brodribb 2005). Provincially significant vegetation communities refer to those currently on record with the NHIC that rank S1, S2 or S3 (see Section 8 for definitions) or are considered significant because of their very low representation in the Region. Current records indicate that there are eight such communities in Peel and Caledon, although discussions with both TRCA and CVC and review of the available ELC mapping for the study area indicate that there are most likely additional significant vegetation communities in the Region that have yet to be properly documented or mapped. The deadline for updating the ELC is not established but will be completed through CVC s Natural Areas Inventory Study to be finalized sometime after the Region s PROPR exercise. Once the ELC mapping is updated, the Region and Town should consider the application of these data for identifying significant wildlife habitat. The current eight communities listed as provincially significant by the NHIC are all contained within the Caledon Slope Forest ANSI in the Town of Caledon and consist of three cliff type communities, three talus (i.e., slopes beneath the cliff face) type communities, and two Sugar Maple forest types (Natural Heritage Information Centre data accessed on-line March 11, 2008). Provincially significant species summarized in Table 6 refer to those that are Species at Risk (SAR) and/or ranked as S1, S2 or S3 (see Section 8 for definitions). Examples of significant non-sar plant species in the Region of Peel/Town of Caledon are Bushy Cinquefoil, Evening Primrose, Wild Lupine and Schreber s Wood Aster. Examples of significant non-sar wildlife species in the Region of Peel/Town of Caledon are Black-crowned Night-heron and Northern Long-eared Bat. In terms of the designated areas and natural heritage features within Peel Region, the following are notable points: The Niagara Escarpment Plan and Oak Ridges Moraine Conservation Plan areas occur only within the Town of Caledon. The majority of the Protected Countryside of the Greenbelt Plan is located within the Town of Caledon, with a small area located in the north end of the City of Brampton. The majority of the Region s designated natural heritage features and areas are also contained within the Town of Caledon (e.g., 78.6% of the Region s Core Greenlands are located within the Town). Relative to the rest of the Region, the Town of Caledon contains a large proportion of unevaluated wetlands. North-South Environmental Inc. page 47 Dougan & Associates Sorensen Gravely Lowes

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