Characteristics of the Oithona similis (Copepoda: Cyclopoida) in the White and Barents seas

Spatial variations in reproductive characteristics of the small copepod Oithona similis in the Barents Sea

“…These CS were similar with the summer values recorded in other Arctic and temperate regions including the southern Barents Sea, the White Sea, the Kara Sea, the Clyde Sea, the North Sea and the Irminger Sea (Marshall 1949, Fomin 1989, Nielsen & Sabatini 1996, Castellani et al 2007, Dvoretskii 2007, Dvoretsky 2008, Dvoretsky & Dvoretsky 2009b. The results of the regression analyses showed that in 2006 temperature and salinity were correlated with CS whereas in 2007 there was no significant correlation (Table 4).…”

“…An increase in body size with latitude and decreasing temperature has been noted for many marine crustaceans including copepods (Clarke 1983, Timofeev 2000. The mean PL of O. similis females found in the present study was higher than in the Greenland Sea, Gulf of Alaska , and the White Sea (Shuvalov 1965, Dvoretskii 2007), but lower than in the North Sea (Nielsen & Sabatini 1996) and comparable with values noted for the Irminger Sea (Castellani et al 2007). According to Shuvalov (1975), populations of O. similis may be classified into different groups (based on female PL), with females from the northern Barents Sea being referred to the ArcticOkhotsk Sea group and individuals from the southern zones being similar to the Atlantic-White Sea group.…”

Morphological plasticity in the small copepod Oithona similis in the Barents and White Seas

“…However, some data on female size variation in Arctic regions is available (Shuvalov 1965, Nielsen et al 2002, Dvoretskii 2007). We found that female PL varied from 450 to 570 µm in the Barents Sea.…”

“…Oithona similis Claus 1866 is widely distributed in the Barents and White seas, forming up to 60 to 80% of the average zooplankton abundance (Prygunkova 1974, Pedersen et al 1995, Dvoretskii 2007. The species plays an important role in the functioning of pelagic ecosystems.…”

“…The species plays an important role in the functioning of pelagic ecosystems. The distribution and life cycle of O. similis were partly studied previously in the Chupa inlet of the White Sea and in the coastal parts of the southern Barents Sea (Prygunkova 1974, Fomin 1978, Dvoretskii 2007). Many aspects of O. similis biology, however, have not been investigated to the same extent.…”