Îlot C (QC026)

Îlot C (QC026)

Îles-de-la-Madeleine, Québec

Site Description

Îlot C is an artificial sand islet that was formed between 1980 and 1982 from sand deposits dredged out of the channel between Dune du Sud and Grande Entrée. Coastal vegetation, dominated by Short-liguled Ammophila (Ammophila breviligulata) has covered a large portion of the islet and contributes to the stabilization of the sand. Red Fescue and other grass and rush species are also present. The islet, however, remains vulnerable to erosion.

Birds

Îlot C became a significant nesting area for large numbers of Common Terns, some Arctic Terns, as well as threatened species such as Piping Plovers and Roseate Terns. Common Terns were the most abundant species, and observers suggest that they comprised at least 95% of the tern population at this site. Over a four-year period from 1987 to 1990, an average of about 1,000 Common Terns was recorded nesting at this site (just over 1% of the estimated North American population). In 1993, the year of the last recent count, surveyors recorded 1445 Common Tern nests.

During the late 1980s and early 1990s, Roseate Terns (identified as nationally endangered) were also consistently recorded at this site. Nesting pairs may have been present in 1987, 1990, and 1993. Since the national population of this species is so low, the regular presence of even one nesting pair represents about 1% of the estimated national population. In the Magdalen archipelago, the nesting Roseate Terns seem to shift back and forth among the three largest tern colonies.

Since 1994, no gulls or terns have been recorded as nesting on Ilot C because of fox predation.

Nesting Piping Plovers (globally vulnerable, nationally endangered) have also been recorded regularly on Îlot C since its formation. During the late 1980s and early 1990s, 5 pairs were recorded each year (about 2% of the estimated Atlantic Canada population). However, from 1993 to 1996 only one pair was present, and in 1997 through 1999 breeding plovers were absent.

In addition to the terns and the Piping Plovers, Herring Gulls (441 pairs in 1993) and Great Black-backed Gulls (505 pairs in 1993) have also nested on Îlot C. Northern Pintail, Horned Lark, Spotted Sandpiper, Savannah Sparrow and Semipalmated Plover are all occasional breeders on the islet.

Conservation Issues

Due to the presence of threatened species, much attention has been directed at this site. The Canadian Wildlife Service has been conducting research on the endangered Piping Plovers in this area since 1987. This information is being used to develop programs that help to increase resident/tourist awareness of the threats facing the threatened Piping Plovers. Due to the sensitivity of these nesting populations, the island should only be observed from a distance, or visited during the non-breeding season.

Efforts are also directed toward the conservation of the nationally endangered Roseate Terns. In the Magdalen Islands, this species of tern nests at only two other locations: the islets off Pointe-aux-Loups, and on Île aux Cochons. Protective measures have been taken at the three colonies to curtail predation by foxes. Electric fences were erected around two colonies, and platforms designed to serve as nest shelters have been set up in each colony to induce the terns to breed.

The nesting birds are also at risk from oil spills, due to the frequent boat traffic travelling through the Gulf of St. Lawrence.

Fish Habitat

Located in a sandy area, the sector is mainly defined by the presence of salt marshes that are home to many marine fish and invertebrates. As the banks of lagoons generally have a gentle slope, the fine particles suspended in seawater, rich in nutrients, are deposited, promoting the development of these swamps gradually as the bottom of the lagoon rises. Around the islands, lagoons are used for aquaculture, shellfish harvesting and recreational activities. The slow current in eelgrass beds makes them a suitable environment for small fish such as stickleback and Atlantic silverside, the tautog tench, the mummichog and for benthic species, including the common crab. The crangon, also called sand shrimp, occupies an important place in the community. By their situation, their connections with the sea and the shallowness of the water collumn, lagoons are the favored growing habitats of American lobster and a spawning site used by many other marine species such as herring, flounder, Atlantic tomcod and rainbow smelt.

The main pressures on lagoons and fish habitats are related to human activities that have increased in recent decades: aquaculture, boating, recreational fishing and road infrastructure are some examples. The discharge of waste and silting are also issues of concern to the quality and sustainability of these habitats.

Major species present:
American eel
American lobster
Atlantic silverside
Atlantic tomcod
Common crab
Crangon (sand shrimp)
Mummichog
Rainbow smelt
Stickleback
Tautog tench
Winter flounder

IBA Criteria Habitats Land Uses Potential or Ongoing Threats Conservation Status

• Northern Gannet1,700 (max.)
• Piping Plover11 (max.)
• Roseate Tern2 (max.)