Brier Island and Offshore Waters (NS021)
Altitude 0 - 30m
Description du site
Brier Island is located at the extreme western end of Nova Scotia, and is about 50 km southwest of the town of Digby. The site includes Brier Island plus tiny Peter Island and the surrounding marine waters for at least 15 km offshore. Brier Island is 7 km by 3 km in size, and is separated from the neighbouring Long Island by the 1 km-wide Grand Passage. Most of the island is forested except for the village of Westport and the fields surrounding it. Two parallel ridges run across the island, with lowlands such as bogs and ponds, in-between. The waters of the Bay of Fundy surrounding Brier Island are rich and diverse in marine life. Right, Humpback, Fin and Minke whales, and White-sided Dolphin occur here.
This island has long been recognized as one of the most important bird areas in the Maritimes, and is considered a mecca for Canadian birders partly due to the diversity of birds that can be seen there. It is a great migration trap for landbirds, and a very important year-round feeding area for marine birds. As of February 2001, 331 species of birds have been recorded in this IBA.
The waters immediately offshore from Brier Island are one of the most important areas for phalaropes in North America. The numbers of mixed flocks of Red-necked and Red phalaropes may regularly number in the millions, although no systematic counts have been made. People frequenting these waters state that 100,000s have been seen annually in August for many years, although researchers seem to be more uncertain about the state of these populations. More specific records include 20,000 Red-necked Phalaropes recorded in 1990, and 10,000 in 1996. In 1984 and 1989, 10,000 and 5,000 Red Phalaropes were reported. Since the global population of Red Phalarope is estimated at 1 million and the North American population of Red-necked Phalarope is estimated at 2.5 million the numbers seen here represent large portions of these species populations. The two phalaropes are often found in tidal streaks, areas where copepods concentrate at the water surface. These feeding areas are associated with underwater ledges found about six and 16 kilometres offshore.
Other marine species seen in large numbers include shearwaters, kittiwakes and alcids. Greater Shearwaters are common in August particularly, with 20,000 recorded in the 1997. Sooty Shearwaters are also common, with smaller and more variable numbers of Manx Shearwater present. Black-legged Kittiwakes are regularly seen in the winter in numbers over 10,000. There is also a record of 40,000 kittiwakes moving past the Northern Point at one point in the 1970s. Thousands of alcids winter in the waters around Brier Island the most common species are Razorbills, Thick-billed Murres, and Dovekie. Numbers of Razorbills are probably significant: 378 were recorded in the winter of 1997/98 on the water, and 8,600 were recorded on passage in 2000.
Banding efforts indicate that the most common landbird migrants in the fall are Yellow-rumped Warbler, Dark-eyed Junco, Golden-crowned Kinglet, White-throated Sparrow, and Magnolia Warbler. Bird banding only occurs over a relatively short period in the fall, but it is thought that if a similar amount of effort were made here as is made in locations such as Long Point in Ontario, the numbers of fall migrants banded might be comparable.
Numbers of migrating raptors are also notable in the autumn. At least 10,000 raptors pass through the area at this time (nationally significant under IBA criteria)., Based on extrapolation, it has been estimated that between 8,000 and 10,000 Sharp-shinned Hawks, and from 3,000 to 4,000 Broad-winged Hawks pass over the area. Peregrine Falcons are also seen frequently.
Flocks of Atlantic Brant pass through the site in continentally significant numbers. For example, 2,000 birds were surveyed in the spring migration of 1997; this represents over 1% of the eastern population. Gulls and terns breed on Peter Island; Roseate Terns used to be part of the colony, but are no longer present.
Enjeux de conservation
There are several whale-watching and seabird-watching boat operations based out of Westport on Brier Island and on adjacent Long Island. In general, tourism interests support conservation of the area due to the relatively high number of visiting birders and nature-oriented tourists. The Nova Scotia Bird Society Sactuary Trust owns Peter Island as a bird sanctuary, and encourages conservation there. Bird-banding has occurred on Brier Island for many years, with fall banding occurring over a 12-week period.
The marine and intertidal areas are overseen by the federal Department of Fisheries and Oceans, while the island is a mix of private and provincial crown land. The Nature Conservancy of Canada owns and manages the 485 ha (1200 acre) Brier Island Nature Preserve, encompassing the entire southern third of the island.
Conservation issues of concern in the area include the overuse of the islands water supply, and limited space. Although there is no longer a large fishery on the island; the only known impact that the fishery has here now is that fish by-products help support a large gull population which in turn can have negative impacts on colonial seabirds, including tern.
Menaces Potencielles ou Existantes
Status de Protection