CCAMLR

Polynyas accelerate oceanic and atmospheric processes. We additionally think polynyas influence biological activity. We pursued daily transition of polynyas in the Ross Sea, Antarctica from 1978 through 1994 using images of sea ice concentrations by the satellite microwave observations. A typical polynya existed in the inner area of the Ross Sea in November of the each year. The shape of the polynya changed remarkably in several days. The polynyas have the range of approximately 500 km from the bottom to the entrance of the Ross Sea. The polynyas usually open to the northern oceanic water late in December in each years except 1982, 1988 and 1992.

Acoustic data from the Polish FIBEX survey in the West Atlantic were examined to check the consistency of krill abundance estimates against the results of the other FIBEX survey vessels. The results indicated that there was a high level of consistency between the results from the Polish vessel and those from the other vessels that operated in the Peninsula region and in the West Atlantic.

Size fractionated chlorophyll-a concentrations of surface seawater was measured (pico-, nano-, and micro-size fractions) during commercial krill operations in the waters north of the South Shetland Islands from late December, 1991 to mid-February, 1992. The proportion of green krill had significant regressions with chlorophyll-a concentrations in micro and nano- size fraction. This result shows the importance of micro- and nano-size phytoplanktons in terms of food source for the Antarctic krill in the natural environment.

The CEMP Standard Methods for monitoring foraging trip duration in Macaroni Penguins recommend using only males. However, males attend the chicks at the nest during most of the brooding period, while the females make frequent foraging trips. We analysed data from 17 males instrumented with VHF-transmitters in the middle of the brooding period (chick age 12-18 days) and 17 females instrumented at the start of the creching period (chick age 25-30 days). Males made their first foraging trips at the start of the creching period. The first trip usually lasted several nights, whereas the subsequent trips were shorter (average 21.8 h). Female foraging trips averaged 27.2 h. No apparent changes in the foraging trip duration of either sex as a function of date were recorded during the creching period. Female attendance periods in the colony where shorter (average 11.9 h) than those of males (average 21.4 h), and females made more foraging trips than males. These results suggest that females might be more appropriate than males as the subjects when monitoring foraging trip duration. In addition, the fact that females spent more time foraging and conducted more foraging trips than males might suggest that female foraging trip duration is more sensitive to changes in prey availability.