831 Tusket Islands
| Geology & Landscape | Freshwater & Wetlands | Soils | Plants Animals | Cultural Environment | Sites of Interest Topics & Habitats |
A submerged coastline with long promontories and inlets characterizes this Unit. The abundant sediment supply allows extensive tidal marsh development. Mild winter conditions permit the survival of relict coastal-plain flora species. Relatively ice-free conditions provide important wintering habitat for waterfowl. Upwelling and tidal mixing create nutrient-rich waters that support a diverse marine fauna.
Geology and Landscape Development
In this part of southwestern Nova Scotia the geological structures intersect the coastline more or less at right angles. As the glacial ice flowed north-south, more or
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| Tusket Islands (aerial view) Click to enlarge |
Drumlins occur onshore and as offshore islands. Glaciofluvial deposits are common, especially eskers. Glacial deposits provide an
ample sediment supply.
Freshwater Environments and Coastal Wetlands
Many medium-sized, elongated lakes are found in the Tusket area. The surface waters tend to be dystrophic and associated with bogs.
The mouths of the Tusket and Chebogue rivers occur in this Unit, and many small freshwater wetlands are associated with the streams and rivers.
Long Savannah and Spinneys Heath are large wetlands considered significant for wildlife. Large peat areas occur around Pubnico Harbour. The coastal
inlets are predominantly lined with salt marshes, which are extensive upriver on the Chebogue and in Little River Harbour and Goose Bay.
Soils
The dominant feature of this Unit is its extensive areas of salt marsh. These are a uniform silt loam in texture and occupy more than 3,200
ha. Upland soils have generally developed from schistose slate or quartzite on drumlinoid land forms, but the central strip from Dunn Lake to Comeau
Hill is an exception, being relatively flat with shallow soils. Better-drained soils are Yarmouth and Mersey, derived from schist and quartzite, and
Medway soils derived from outwash sands and gravels. Imperfectly or poorly drained soils (which are often mottled, indicating saturation for considerable
periods of time) include Deerfield, Riverport, Liverpool, Danesville, Aspotogan, and Pitman. Large peat areas have developed near Pubnico Harbour. The
islands are nearly all either Mersey (drumlins) or Liverpool soils.
Plants
Areas of Yarmouth, Deerfield, Medway, and Mersey soils are often cleared for agriculture. Otherwise they normally support good growths
of White Spruce and Balsam Fir, with Red Maple, birch, and poplar. Better drained, more sheltered sites may have some pine or oak. Black Spruce and
larch swamps are common. Because of the fairly high rate of erosion, the transition from salt marsh to spruce woods is often quite abrupt. A fringe of grey,
dead trees is usually found at the rear of the salt marshes, where the rising sea level drowns their root systems. The Southwestern floral element is
well represented in this Unit, particularly along river and lake margins and in bogs. Examples include a bladderwort and Curly-grass Fern (see Figure 13).
Animals
The mild winter temperatures, the many islands and sheltered inlets, and the extensive areas of salt marsh and intertidal sands and
muds produce a very important wintering area for waterfowl and certain other species such as the Bald Eagle. Present in the greatest numbers are the
Black Duck, Canada Goose, scaups, and the Common Goldeneye. Less common birds include the Red-breasted Merganser and Oldsquaw. Shorebird
numbers as the birds begin to arrive in spring are small, then peak in early to mid-August, and sharply decline in September. Osprey breed along this shore
and Leach's Storm-petrel breeds on the Tusket Islands.
A rich marine fauna is associated with this Unit. The warmer inshore waters support a number of invertebrate species with a more southerly distribution. An area of upwelling offshore, combined with tidal mixing, provides nutrient-rich waters which support abundant algae, crustaceans, and open-sea fish. The Tusket supports a large run of Gaspereau in the spring. The introduced Chain Pickerel has had a major impact on species in this Unit. It is a predator of both migratory and exotic freshwater fish, and is thought to have played a critical role in the extirpation of the Atlantic Whitefish in the Unit. Two anadromous species, Rainbow Smelt and Striped Bass, are also found here.
The more fertile soils derived from schists result in more productive inland waters and a fairly diverse freshwater fauna, particularly molluscs. The fauna also includes a southwestern element, the best known example being the Atlantic Whitefish.
Cultural Environment
Acadian settlement in this area was based around the tidal marshes. Pubnico is derived from the Mi'kmaq word "Pogomkook,"
meaning "cleared land," a landscape favoured by the Acadians. The productive herring, lobster, clam, and scallop fisheries continue to provide an
important economic base. Rockweed and Irish Moss are commercially harvested. Hydroelectric power has been harnessed by a generating station at Tusket
Falls. Large sand and gravel deposits have been commercially exploited. Mi'kmaq shell middens have been found in the Tusket Islands area. In the early
1990s, exercise of aboriginal hunting and fishing rights led to confrontations over unregulated native fishing practices. The name Tusket is derived from
the Mi'kmaq word "Neketaouksit" meaning "the great forked tidal river." Migratory bird populations of Seal Island attract bird-watchers to this Unit.
Sheep were left to graze year-round on the Tusket Islands.
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