Investigations of intensity of krill drift near South Georgia Island

Calculation of drift’s speed (transport with current) of Antarctic krill along the northeastern shore of South Georgia Island (between 54-55S and 34-39W) were carried out. Length of island’s shelf for calculation was assumed about 300 km, but average width of shelf (from shore to 500 m isobate) was assumed about 60 km. Speed of drift in these spatial limits was assumed about 10 cm sec-1. The average density of krill before the beginning of transport along the island’s shore was assumed about 0.1 g m-3.
Total amount of krill immigration on island’s shelf (in above indicated limits) were examined for three main types of water circulation (the typisation according to Maslennikov, 1979).
Duration of krill drift (from the beginning of immigration and to the end of emigration) along the northeastern shore of South Georgia fluctuated from 35-37 days to 75-100 days. For separate cases this duration was valuated as much as 140-150 days (when crustaceans are transported back again on shelf zone at the conditions of the first type of water circulation). The minimal period of krill presence near island is expected for the third type of water circulation, but maximal duration of krill presence here is suggested for the first type of water circulation. Total renewal krill, which is immigrated into shelf waters of island is supposed to take place not less than 2-3 times per year. Peculiarities of accumulation and drift of krill related to the consequence of types of water circulation change are examined.