Hamilton Waterfalls

Dundas Valley

General Summary

The Dundas Valley study area encompasses an extensive natural area located on the northwestern fringe of the Hamilton-Dundas-Ancaster urban centre. The core of this area consists of varied, relatively undisturbed, broadleaf and mixed upland woods. The periphery consists of a patchwork of natural areas, active and abandoned agricultural fields, and rural residential estates.

Significance

Ontario Ministry of Natural Resources Designation:
• Provincial Life Science ANSI (Area of Natural and Scientific Interest)
• Provincial Earth Science ANSI (Area of Natural and Scientific Interest)

City of Hamilton Environmentally Significant Area (ESA) Criteria:
• Significant Earth Science Feature

- the varied landforms within this area are considered

• Significant Ecological Function

- the area contains significant species

- the area is a large core natural area and contains interior forest habitat (at least 100-200m from forest edge)

- the area contains a high diversity of native plant species and biotic communities

- the natural area serves as a link between natural areas including the Niagara Escarpment corridor

- the area is a good representative of high-quality upland woods, which are poorly represented in the region, and also contains coldwater fish habitat

• Significant Hydrological Function

- the area helps to maintain hydrological balance over a large area and maintains surface water quality in the many streams that flow through it

Physical Description

The Dundas Valley study area encompasses most of the western half of a major re-entrant in the Niagara Escarpment, extending up to 6 km across the full width of the valley, and some 9 km along the valley axis. The upper section of this escarpment valley is completely buried beneath deep glacial deposits, which form a hummocky, dissected topography with rolling hills and steep-walled stream valleys. The Dundas Valley is filled to a depth of over 200 m with glacial till. The grey facies of the Halton Till, referred to as the “Dundas facies”, is unique to the Dundas Valley. Significant groundwater discharge is indicated by the presence of springs (including Mineral Springs and Sulphur Springs), an artesian well along Sulphur Springs Road, and permanent coldwater streams.

Ecological Land Classification

The varied topography of the Dundas Valley provides a range of slopes, exposures, and moisture regimes which support varied species associations. The central valley and ridge forests, in particular, are considered representative of an upland woods system on a rolling till substrate. The south-facing slopes provide a warmer microclimate which supports a number of Carolinian species.

Flora and Fauna Summary

Vascular Plants

Nature Counts botanists and ELC surveyors documented 262 species including 17 Carolinian species and 48 (18%) non-native species. Data from botanical surveys conducted in the area document 585 species including 16 Carolinian species and 14 prairie/savannah species. In addition, two provincially rare species, 43 locally rare species, 44 locally uncommon species, the locally uncommon and provincially rare Green Violet (Hybanthus concolor), and three locally, provincially, and COSEWIC listed species, including American chestnut (Castanea dentata) and Broad Beech Fern (Phegopteris hexagonoptera), are all found within the area.

Butterflies

Nature Counts surveyors recorded 47 species in 2001 and 2002. Of these, eight are locally uncommon species, two are locally rare species, and one is a COSEWIC special concern species. A total of 57 species, including the provincially rare Giant Swallowtail (Papilio cresphontes) and 17 others listed as significant, have been recorded here.

Fish

Ancaster Creek arises above the Niagara Escarpment and enters the Dundas Valley after dropping over at Sherman Falls. Ancaster Creek and its tributaries, Sulphur Creek and Spring Creek (which arise from springs and seepage) are all coldwater or potential coldwater streams flowing through a mainly forested area. Fish were assessed in the Dundas Valley between 1986 and 2000. In total, 32 species have been collected with one species, Sea Lamprey (Petromyzon marinus), recorded only since 1990 and considered significant in the City of Hamilton.

Herpetofauna

A total of 24 species have been recorded here. In 2001 and 2002, Nature Counts surveyors recorded a total of 13 species including three that are locally uncommon and Jefferson Salamander (Ambystoma jeffersonianum), a locally, provincially, and nationally rare salamander species. The Eastern Milk Snake (Lampropeltis triangulum triangulum) and the Ribbon Snake (Thamnophis sauritus), also found within this area, are COSEWIC special concern species.

Breeding Birds

The Dundas Valley contains two highly significant bird species: the nationally endangered Acadian Flycatcher (Empidonax virescens) and the nationally threatened Hooded Warbler (Wilsonia citrina). Nature Counts surveyors recorded a total of 85 species in 2001 and 2002 including 15 interior forest species, 27 locally uncommon species, and 6 locally rare species, of which the COSEWIC special concern species, Cerulean Warbler (Dendroica cerulea) and Louisiana Waterthrush (Seiurus motacilla) are two. A number of field surveys took place between 1983 and 1999 that documented a total of 100 species, including 51 significant species.

Mammals

The Nature Counts project conducted small mammal trapping in 2001 and 2002. Sixteen species were recorded, including four new records for the area.