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Le gisement de Rimouski est le plus grand et Kamouraska suit avec 1,8 km2. Les gisements Îlets D'Amours (0,1 km2), Anse aux Coques (0,1 km2), Baie Hâtée (0,2 km2) et Capucins (0,2 km2) n'occupent, pour leur part, que des surfaces restreintes.
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In 2005 and 2006, a little over 19 km2 of foreshore were surveyed on the south shore of the St. Lawrence Estuary, between Kamouraska and Capucins. Fourteen sites were sampled in 2005 and three of them, Pointe des Riou, Rimouski and Capucins, were revisited in 2006. Survey results show that these beds cover an area varying between 0.1 to 4.5 km2. The Rimouski bed is the largest followed by Kamouraska, which measures 1.8 km2. The beds at Îlets D'Amours (0.1 km2), Anse aux Coques (0.1 km2), Baie Hâtée (0.2 km2) and Capucins (0.2 km2) cover smaller areas. Work conducted at Anse des Méchins (Petits-Méchins) failed to locate any clam aggregation there. The size of the beds surveyed often differs from what is presented in the literature. Part of the discrepancies recorded could be on account of methodological differences or changes in environment or habitat. Most of the sampled beds are located in proximity or at the mouth of rivers and are usually exposed to north winds (NW, N and NE). In 2005, legal size clams (≥51 mm) were absent from Kamouraska, Anse au Persil and Îlets D'Amours beds. In the other beds, the mean density of legal size clams varies from 3.4 individuals/m2 at Batture de Tobin to 32.5 individuals/m2 at Capucins. Maximum densities recorded for this category of clams vary between 25 and 150 individuals/m2. Results from 2006, at Pointe des Riou, Rimouski and Capucins differ from 2005. These differences could be explained by very small scale changes in abundance and demographic structure, seasonal and annual variations of these two parameters and by the methodologies used. The maximum size of clams is less than 60 mm on the beds located west of the surveyed area, but reached, except for Baie du Ha! Ha! and Anse aux Coques, nearly 80 mm over those located east of Batture de Tobin. Results from work conducted on a few experimental plots suggest a more rapid growth at Pointe des Riou, intermediate at Capucins and weaker at Rimouski. Comparisons of allometric relations for each of these three beds, relations that are determined using specimens collected over larger areas suggest however, that for the same lenght, clams coming from Rimouski have a whole weight and a weight of dry viscera higher than to the others sites. Among all the sampled sites in 2005 and 2006, Rimouski and Capucins stand out on account of, among other things, their easy access, good protection of winds, strong clam abundance, a high percentage of colonized area and a demographic str
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