Bonaventure Island

Site description (2001 baseline):

Site location and context
Bonaventure Island is located on the Gulf of St Lawrence approximately 3.5 km from the shore of the Gaspé Peninsula. The 416 ha island is roughly circular in shape with cliffs on the southeastern and northeastern shores rising to a height of approximately 75 m. The island lies within the Atlantic Highlands biome with balsam fir and spruce being dominant species. The cliffs and shorelines are generally devoid of vegetation with the exception of some arctic / alpine species that are able to withstand the harsh microclimate. Thus far, 572 vascular plant species have been recorded on the island, including eight that are rare in the province of Quebec and five that are provincially vulnerable or threatened.

Key biodiversity
Bonaventure Island is renowned for its Northern Gannet colony. In 1994, over 32,000 breeding pairs were observed making it the largest colony in North America. Using population estimates from the late 1980s, there may be as much as 9% of the global population and approximately 50% of the North American population present at Bonaventure Island during the breeding season.

In addition to Northern Gannets, equally impressive numbers of Black-legged Kittiwakes and Common Murres also nest on the cliffs. In 1989, over 23,000 pairs of Black-legged Kittiwakes were recorded, representing as much as 9 to 12% of the western Atlantic population. In the same year, almost 28,000 pairs of Common Murre were recorded. This represents approximately 5% of the eastern North American Common Murre population. The island is clearly of global significance for nesting colonial seabirds.

Other seabirds nesting on the island include Double-crested Cormorant, Great Black-backed Gull, Herring Gull, Black Guillemot, Razorbill, Atlantic Puffin, and Leach's Storm-Petrel. In all, ten different seabird species nest on the island. During the summer and early fall Harlequin Ducks from the eastern population (nationally endangered) concentrate around both the island and Percé Rock. Numbers observed have been as high as 118 individuals (early September 1989).

In addition to seabirds, the island supports a typical community of boreal forest birds (Blackpoll Warbler, Boreal Chickadee etc.) and other habitat generalists in the abandoned fields. As of 1985, 218 bird species had been observed within the park.

Conservation responses/actions for key biodiversity
Bonaventure Island was permanently settled from 1787 to 1963. Over this period, much of the island was cleared for agriculture and during the 19th century the seabird colonies were heavily exploited for food and other uses. At the turn of the century declining numbers of seabirds became an increasing concern and resulted in the government declaring the eastern and northern cliffs a federal migratory bird sanctuary (1919).

A few summer residents remained after this date until the Québec Government purchased the island in 1971. The provincial park (Parc de L'Ile-Bonaventure-et-du-Rocher-Percé) was declared in 1985. As a "conservation park," the conservation of ecological features is of prime importance. Currently the park has 15 km of hiking trails, conservation zones where access is controlled, and an "intense conservation zone" which prohibits direct access to some seabird colonies.

The park is a popular tourist destination, with the seabirds being the main attraction. Approximately 60,000 people visit the island each year. Fences, observation platforms, and programs to increase public awareness are used to minimize disturbance to the birds.

Recommended citation
BirdLife International (2023) Important Bird Area factsheet: Bonaventure Island. Downloaded from on 02/10/2023.