IBA Eastern Cape Sable Island
Clark's Harbour, Nova Scotia
Site Summary
NS016 Latitude
43.426° N
65.610° W
0 - 20 m
33.62 km²
mixed woods (temperate), scrub/shrub, salt marshes/brackish marshes, mud or sand flats (saline), coastal sand dunes & beaches, open sea, inlets/coastal features (marine), urban parks/gardens, other urban/industrial areas
Land Use:
Fisheries/aquaculture, Hunting
Potential or ongoing Threats:
Disturbance, Hunting, Urban/industrial development
IBA Criteria: Globally Significant: Congregatory Species, Shorebird Concentrations, Migratory Landbird Concentrations, Nationally Significant: Threatened Species, Congregatory Species
Conservation status: IBA Conservation Plan written/being written
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Site Description
Cape Sable Island is the southernmost accessible point of Nova Scotia. It is a large, fairly flat and often foggy island with roads frequently situated close to the shoreline. Sand beaches, extensive mud flats, and salt marshes are the predominant shoreline habitat types. Inland on acidic soils are alder thickets, and low forests containing Black Spruce and several heath plants, as well as residential gardens. Sheep grazing commonly occurs inland. The IBA covers most of the island, south of a line from the town of Centreville to Bulls Head.
Spring and fall migrants of many types use Cape Sable Island as a stopping point. The most numerous and significant of migrants are shorebirds. The coast around South Side Inlet and south and west of The Hawk are the best areas for shorebirds. In July 1993, an amazing one quarter million Semipalmated Sandpipers were estimated to be at Cape Sable Island, and at the same time of year in 1995, 15,000 Short-billed Dowitchers were recorded. This represents possibly 7% and 5% respectively, of the global populations of these two species.

Participants in the Maritimes Shorebird Survey (MSS) have surveyed the site since 1977, but coverage has varied among years. In some years, only a small part of the site was covered. MSS protocol requires volunteers to count shorebirds every second weekend during the period of southward migration from late July to late October. So, seasonal totals from the MSS could include up to seven one-day counts. From 1994 to 1996, an average of 2,731 Semipalmated Plovers, more than 1% of the estimated global population were recorded. Black-bellied Plovers also frequent the site, with a three-year average (1985, 1987 and 1995) of 504. MSS results show that thousands of Sanderlings and hundreds of Ruddy Turnstones, Least Sandpipers, and White-rumped Sandpipers are also found at this site. Greater Yellowlegs and Willets visit the site during fall migration, but numbers are typically low. Diversity of shorebirds and numbers of wintering Black-bellied Plover, Sanderling, Red Knot, Dunlin and Ruddy Turnstone are higher here than any other location in Atlantic Canada.

In the summer, the Piping Plover, a species endangered in Canada and globally vulnerable, nests along the sand beaches on the eastern side of the island. The 11 birds recorded in 1996 on Cape Sable Island (mostly at Danielss Head) represented about 2% of the Canadian Atlantic population of Piping Plover. Canadas first breeding American Black Oystercatchers bred on the island in 1997 and 1998.

In late winter and early spring thousands of Brant congregate on the flats of Hawk Channel, with a high count of 8,000 recorded in April 1997. This is about 6% of Atlantic Brant (the population of Brant that winters on the Atlantic coast after breeding in the eastern High Arctic) and about 2% of all North American Brant.

A high diversity of waterbirds also use Cape Sable Island, particularly in the spring and fall. Loons, herons, egrets, cormorants, seaducks, bay ducks, alcids and pelagic species are all seen here. Landbird diversity is equally rich. Warblers, vireos, tanagers and sparrows are all typical migrants. When the weather gets exceptionally stormy and migrants are thrown off course, unusual species and large numbers of landbirds are found at Cape Sable Island. For instance, in the fall of 1998 when such an event occurred, 500 Indigo Buntings, 4 Kentucky Warblers, 20 Hooded Warblers, 4 Worm-eating Warblers and 20 Blue Grosbeaks were amongst the thousands of birds seen.

IBA Criteria
SpeciesT | A | I Links Date Season Number G C N
Brant 1997 SP 8,000
Brant 1998 WI 4,000
Dovekie 2013 - 2020 WI 65 - 75
Manx Shearwater 2016 - 2020 SU 4 - 15
Northern Gannet 2016 - 2018 FA 2,500 - 3,000
Piping Plover 2008 - 2020 FA 4 - 11
Piping Plover 2016 - 2018 SP 4 - 8
Piping Plover 1996 - 2020 SU 4 - 14
Razorbill 2019 FA 632
Roseate Tern 2016 - 2020 FA 2 - 20
Roseate Tern 2018 - 2019 SP 2 - 3
Roseate Tern 1997 - 2020 SU 2 - 14
Sanderling 1998 - 2014 FA 2,430 - 5,000
Savannah Sparrow 2000 - 2020 FA 20 - 80
Savannah Sparrow 2014 - 2019 SP 18 - 55
Savannah Sparrow 2013 - 2020 SU 18 - 60
Semipalmated Plover 1991 - 2012 FA 1,130 - 4,600
Semipalmated Plover 2000 - 2008 SU 1,345 - 3,380
Semipalmated Sandpiper 1998 - 2012 FA 18,300 - 35,000
Semipalmated Sandpiper 1993 SU 250,000
Short-billed Dowitcher 1991 - 2019 FA 1,155 - 6,715
Short-billed Dowitcher 1995 - 2020 SU 1,200 - 15,000
Note: species shown in bold indicate that the maximum number exceeds at least one of the IBA thresholds (sub-regional, regional or global). The site may still not qualify for that level of IBA if the maximum number reflects an exceptional or historical occurrence.
Conservation Issues
In the past illegal hunting was a problem in the Cape Sable Island region. Although this problem has not disappeared, it has greatly decreased in the last decade or so. Easy access and the proximity of roads and residential areas also mean that disturbance of breeding plovers or shorebirds feeding along the shorelines is a potential problem. The presence of a keen local birding community may help to mitigate this problem. Any future shoreline and inland development could effect the quality of habitat that migrants prefer and thus would ideally be subject to critical examination.

The IBA Program is an international conservation initiative coordinated by BirdLife International. The Canadian co-partners for the IBA Program are Birds Canada and Nature Canada.
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