Geology and Landscape Development
The Mabou Highlands lie southwest of the Cape Breton highlands on the Northumberland Strait. They form a rounded knoll 15 km by 8 km which reaches an elevation of 335 m at the north end and 320 m at the south end. The surface of the Mabou Highlands is highly dissected, and little remains of the original plateau. The sides are deeply eroded. The area is underlain by two rock types: one is a series of metamorphosed sedimentary and
volcanic rocks, and the other is a gneiss complex. Both are probably Precambrian in age and are comparable to similar rocks found in the Cape Breton highlands (Regions 100 and 200). Both are very resistant to erosion. The western boundary of this block of Avalon crust is a north-south fault which has set Devonian-Carboniferous sandstones against the Precambrian strata.
The Mabou Highlands are almost entirely surrounded by Horton strata, but unlike other sections of the Avalon Uplands, they stand out in high relief against these rocks. At the boundaries the hills rapidly climb to 200 m above the Horton deposits. There are steep cliffs along the rather even Northumberland coastline from Port Ban to Cape Mabou.
Coarse glacial deposits lie against the lower slopes of the Mabou Highlands south of Inverness. Other finer sandy deposits are found on the banks of Broad Cove, ascending to more than 150 m above sea level.
Streams that flow in wide valleys near the crest of the Mabou Highlands occupy deep gorges further down the slopes and are separated by rounded valley shoulders. The drainage exhibits a radial pattern, with stream systems draining outwards from the rounded crest.
Groundwater springs and seeps can be found in areas with colluvial deposits.
The main soil series is Thom, a well-drained, stony, sandy loam. Thom soils are heavily podzolized, with a thick iron humate B horizon. Small areas of peat are common in depressions.
Away from the immediate influence of the winds off the Gulf of St. Lawrence, shade-tolerant hardwoods dominate the upland plateau in this Unit, with Sugar Maple, Yellow Birch, and American Beech being the main species. White Spruce and Balsam Fir are found on coastal sites, while Balsam Fir, spruce, and Eastern Hemlock form softwood stands or mixedwood stands with Red Maple and birch on the lower slopes. A large area around South
Cape Mountain has been cleared for use as a community pasture.
Trapping in the northern part of the Mabou Hills in July and September 1982 revealed that no Rock Voles or Gaspé Shrews were present, but otherwise the small-mammal fauna was diverse. Bald Eagles are frequently seen near Mabou Harbour.
The marginal farmland of the Mabou Highlands was settled by Scots in the mid-nineteenth century, with subsistence agriculture and sheep farming forming much of the economic base, together with the timber trade and mining nearby. Many of these farms were later abandoned, and forest succession ensued. However, sheep farming is still practised here today. The Sight Point Walking Trail has long been a recreational attraction here. Seasonal hunting also takes place in these highlands.
Sites of Special Interest
- Sight Point - exposures of Precambrian intrusive rocks
- Inverness and Broad Cove - raised beaches
Provincial Parks and Park Reserves
Proposed Parks and Protected Areas System includes Natural Landscape 60.
- Sight Point, Glenora Falls
The Avalon and Meguma Zones
Terrestrial Glacial Deposits and Landscape Features
Birds of Prey
Animals and Resources
Hardwood Forest (Sugar Maple, Yellow Birch, Beech Association)
Mixedwood Forest (Spruce, Fir, Pine-Maple, Birch Association