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.
Bonaventure Island is famous for its Northern Gannet colony. In 2012, more than 51,700 breeding pairs were observed making it the largest colony in North America and the world.
The cliffs of Bonaventure Island and Percé Rock are also home to an equally impressive number of Black-legged Kittiwakes and Common Murres. In 2013, approximately 8200 pairs of Black-legged Kittiwakes were recorded, making this colony one of the largest in the Gulf of St. Lawrence; nearby Forillon and Anticosti Island also support large numbers of Black-legged Kittiwakes. These three colonies combined are home to about 70% of the breeding population within the Gulf. In 2008, 17, 272 pairs of Common Murres were observed, which corresponds to about half of its population within the Gulf.
Eleven species of seabirds breed here, the most common being Double-crested Cormorant, Great Cormorant, Great Black-backed Gull, Herring Gull, Black Guillemot, and Razorbill. Harlequin Ducks can also be found frequenting the waters surrounding this IBA during the summer and early fall. Harlequin Ducks (eastern population) are listed as a nationally endangered species.
In addition to seabirds, Bonaventure Island IBA supports a typical community of boreal forest birds such as Blackpoll Warbler and Boreal Chickadee along with other habitat generalists that frequent the fallow fields. In total, 218 species of birds have been recorded here.
Note: species shown in bold indicate that their population level (as estimated by the maximum number) exceeds at least one of the IBA thresholds (national, continental or global). The site may still not qualify for that level of IBA if the maximum number reflects an exceptional or historical occurence.
Bonaventure Island was permanently settled from 1787 to 1963. Over this period much of the island was cleared for agriculture. 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 the Canadian government declared the eastern and northern cliffs a federal migratory bird sanctuary in 1919. By 1963, just a few summer bird residents remained which prompted the Québec government to purchase the island in 1971, and in 1974 Percé Rock was added to this nature reserve. In 1985, this area became a provincial park, Parc de l'Île-Bonaventure-et-du-Rocher-Percé, where preservation of ecological features is key. 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.
Since 2010, the breeding success of the Northern Gannet is declining at an alarming rate. In 2013, the chicks survival rate was 36%, which is superior to the rate recorded over the past two years, but far away from the historical average of 70%. Several research teams are trying to improve understanding of the root causes. A potential cause is the warming of the Gulf's surface waters leading to changes in the distribution of the fish stocks on which the Northern Gannet is feeding.
The IBA Program is an international conservation initiative coordinated by BirdLife
International. The Canadian co-partners for the IBA Program are Bird Studies Canada and Nature Canada.