Site description (2001 baseline):
As recently as 1980, up to 100,000 phalaropes - mostly Red-necked Phalaropes - were reported in the waters around Grand Manan Island . Since then such large numbers have not been recorded, and the reasons for the decline are not known. Other pelagic birds that feed in these waters include thousands of Greater, Shearwaters and Wilsons Storm-Petrels (10,000 of the latter in July 1997).
Coastal-feeding migrants, such as most shorebirds, are common in migration. Probably at least 10,000 shorebirds (a nationally significant number) can be found along the coastal parts of this site in the fall although total numbers have not been systematically counted. One species often found in large numbers is the Semipalmated Plover. The surveyors of the multi-day Maritime Shorebird Survey noted that in some years 1,000 birds utilized Kent Island alone (perhaps 2% of the global population). Black-bellied Plover, Greater Yellowlegs, and Least Sandpiper are also common species.
In the late winter and early spring Brant are found by the thousands along parts of the coast, especially at: the west side of Kent Island, Cow Passage, Grand Harbour, around Low Duck Island, and in Castalia Provincial Park. Probably at least 1% of the North American Brant population are found here typically (3000 birds), but 10,000 were recorded in April, 1997.
In addition to Razorbills, a few other species winter in notable numbers. Over 350 Purple Sandpipers gather on the rocky shores in small to medium sized flocks. This number is about 3% of North American population of the species. Great Black-backed Gull numbers can also be high (826 were counted in Dec 1997), Common Eiders are common in winter, and the nationally endangered Harlequin Duck is sometimes seen in large numbers (43 off White Head Island). Small numbers of Dovekies, Common Murres, and numerous other species can also be seen in this season.
Kent Island supports a large breeding colony of Herring Gulls which seems to have been declining over the years. A rough estimate of 25,000 pairs comes from earlier in the century, 1,441 pairs were present in 1984, and in 1998, 940 pairs were present. This colony plus others on other islands (including Great Duck, Sheep and West Green islands) total 1910 pairs, or 1.5% of the North American population. In the early 1980s, about 900 pairs of Common Eiders nested on Kent Island (approximately 1% of the dresseri subspecies population), and in addition more eiders nest in other parts of the IBA. About 1000 pairs of Leachs Storm-Petrels also breed here. In total, about 200 bird species have been recorded on this small island.
Grand Manan also hosts large landbird concentrations during migration. On Grand Manan Island, Castalia Marsh, South Head, and North Head are of particular importance to landbirds. The adjacent Kent Island is also used as a landfall by migrating landbirds.
Concerns over the environmental health of the oceanic portions of the ecosystem at this site centre on two general themes: water quality and the harvesting of aquatic organisms. Numerous natural resources are harvested to varying degrees within this site including: herring (using both fixed gear and purse-seining), lobster, scallops, aquaculture-raised salmon, sea urchins, sea-cucumbers, marine algae (both the traditional dulse and the newer harvest of rockweed, Ascophyllum nodosum), and gulls eggs. One or more of these activities may have an effect on the bird populations in the archipelago. For instance one company has applied to harvest 17% of the standing biomass of all brown algae (includes rockweed) on Kent Island. These mats of algae are used by eiders when raising their young, and by migrating shorebirds. Also, salmon aquaculture may be allowed to occur within 160 m of this islands shoreline.
Waters east of Grand Manan Island are part of a shipping route to Saint John, New Brunswick. Thus, as with many oceanic sites, oil spills are a potential threat. Additionally, the water quality may have been compromised by radio-nuclides, chemical and thermal effluents from the Point Lepreau Nuclear Power Plant, and other industrial contaminants from other sources.
Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Grand Manan Archipelago (Canada). Downloaded from
https://datazone.birdlife.org/site/factsheet/grand-manan-archipelago-iba-canada on 27/12/2024.