Witless Bay Islands (NF002)
Mobile, Newfoundland and Labrador
Latitude 47.223°N
Longitude 52.792°W
Altitude 0 - 86m
Area 62.08km²
The Witless Bay Islands are located 4 km off the east coast of the Avalon Peninsula, approximately 35 km south of St. John's, Newfoundland. The site consists of four small islands: Green, Great, Gull, and Pee Pee. All are rocky, with low cliffs and steep, grassy slopes. The two larger islands, Great and Gull, also support coniferous forest communities.
The Witless Bay Islands support a globally significant colony of breeding seabirds. Great Island, in particular supports the largest colony of Atlantic Puffins in eastern North America. A breeding population of more than 216,000 breeding pairs (some on Gull island as well) was estimated in 1994. This represents approximately 3.6% of the global population and possibly as much as 57% of the eastern North America population.
Also present on the Witless Bay Islands are impressive numbers of Leach's Storm-Petrels, Common Murres, Black-legged Kittiwakes and Herring Gulls. Nearly 780,000 pairs of Leach's Storm Petrels have been recorded in the area (the majority breeding on Great and Gull Islands). This estimate represents approximately 9.5% of the global and 16% of the western Atlantic population. Approximately 77,500 pairs of Common Murres have also been reported (almost 2% of the Atlantic and over 13% of the eastern North American breeding population). Black-legged Kittiwakes also breed on the islands. Approximately 43,500 pairs have been estimated, which represents as much as 16 to 22% of the western Atlantic breeding population. Approximately 7,000 pairs of Herring Gulls (approximately 5% of the eastern North America population) have also been recorded. Other species of seabirds nesting on these islands include Great Black-backed Gulls, Black Guillemots, Thick-billed Murres, Razorbills, and Northern Fulmars. The marine areas surrounding the islands are also important for migrating sea ducks such as White-winged and Surf Scoter, Oldsquaws, and Common Eiders.
The Witless Bay Seabird Sanctuary Ecological Reserve, which includes Gull, Green, and Great Islands, was established in December, 1983 under the Wilderness and Ecological Reserves Act. As a result, the islands are shielded from most direct threats. There is however, increasing concern about the levels of ecotourism. During the peak of the season, as many as 10 to 15 tour boats per day visit the area. The auks, in particular, appear to be sensitive to the disturbance.
The colony is a base for a series of long-term ecological studies of seabirds, sponsored by the Canadian Wildlife Service and Memorial University of Newfoundland.
IBA Criteria Habitats Land Uses Potential or Ongoing Threats Conservation Status
Hosted by Bird Studies Canada
NatureCounts monthly abundance barchart
Razorbill500,000 (max.)
Atlantic Puffin500,000 (max.)
Common Murre800,000 (max.)
Leach's Storm-Petrel1,560,000 (max.)
Black-headed Gull20 (max.)
Black-legged Kittiwake87,000 (max.)
Herring Gull13,990 (max.)
Globally Significant:
Congregatory Species
Colonial Waterbirds/Seabird Concentrations
Coastal cliffs/rocky shores (marine)
Coniferous forest (boreal/alpine)
Rocky flats & barrens
Sedge/grass meadows
Nature conservation and research
Oil slicks
Other increased mortality
Ecological Reserve (provincial)
IBA Conservation Plan written/being written
750 - 500,000 2014 Summer
1,000 2010 Summer
200 1985 Other
8,000 - 100,000 2017 Fall
100,000 2017 Summer
10,000 - 100,000 2017 Spring
8,000 2016 Fall
50,000 2016 Summer
10,000 2016 Spring
15,000 - 20,000 2015 Summer
20,000 - 500,000 2014 Summer
15,000 2013 Fall
9,000 - 10,000 2003 Summer
250,000 2017 Spring
250,000 - 500,000 2016 Summer
100,000 2014 Fall
155,000 1985 Other
Leach's Storm-Petrel
1,560,000 1994 Summer
Black-headed Gull
20 2012 Summer