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.
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.
BirdLife International (2020) Important Bird Areas factsheet: Îlot C. Downloaded from http://www.birdlife.org on 16/07/2020.