Growth of nototheniid fish, Trematomus bernacchii and Pagothenia borchgrevinki reared in aquarium

Antarctic nototheniid fish, Trematomus bernacchii and Pagothenia borchgrevinki were reared in the aquarium at the Kamogawa Sea World, Japan. Two T. bernacchii and 4 P. borchgrevinki individuals survived for about 2000 days in good condition. Growth in the body length and body weight of both species was observed. One individual of T. bernacchii spawned once a year since 1984. During about 1 month before spawning the fish stopped feeding. The similar behavior in feeding was observed in the other individual of T. bernacchii

Long-term culture of Antarctic seaweed, Phyllophora antarctica (Rhodophyta), sampled at Syowa Station

Fronds of the Antarctic seaweeds, Phyllophora antarctica and Phycodrys antarctica fronds, attached to sea urchins (Sterechinus neumayeri) caught with a bait-trap, were collected from ice-covered shore of Kita-no-seto Strait near Syowa Station during the 1982 summer. For about three months, Phyll. antarctica fronds were maintained at approximately 0℃ in the refrigerator of the icebreaker FUJI. After April 1982,they were maintained in a glass culture tank at Kamogawa Sea World, Chiba, Japan. Aerated seawater was supplied through a closed re-circulation system; water temperature was kept between -1.9 and 1.5℃ The tank was illuminated with a 10W day-light fluorescent tube (12h light, 12h dark). Phyll. antarctica survived in the tank for 16 years. Producing new growth at the margin of the original fronds, the old parts decayed. Consequently the biomass of fronds increased 20-30 times. It was noted that the biomass increase was greater with the cohabitation of such animals as fish, echinoids, asteroids, gastropods and nemertineans than that when the seaweeds were maintained without animals. In the 1985 summer, fronds of the same Phyll. antarctica were again collected by the same method. The fronds were taken to the Usa Marine Biological Institute, Kochi University, Japan. Those fronds were cultivated in 200ml of enriched seawater with SWII medium in dishes (500ml). The fronds were kept in an incubator 5℃ in fluorescent light ranging from 5-50μE・(cm)^・s^(12L/12D). The fronds survived for 3 years under the lower light conditions, but their growth was lower and their size was smaller than the fronds cultured in Kamogawa Sea World. Newly collected fronds were also maintained in dark conditions at 0-5℃ The fronds survived well for one year but then died after de-colarization of fronds after 3 years. We concluded that the survival of Phyll. antarctica was better at 0℃ than at 5

EGGS RELEASED BY THE NOTOTHENIID FISH TREMATOMUS BERNACCHII BOULENGER IN CAPTIVITY (Eleventh Symposium on Polar Biology)

In the morning of 24 April 1988, eggs were released by a single fish of the nototheniid Trematomus bernacchii which were reared in an aquarium of the Kamogawa Sea World, Chiba Prefecture, Japan. The 4811 eggs were liberated on sand. Eggs were adhesive, semi-transparent, milk-white in color, and 4.4-4.7 mm in diameter. The 1988 results were compared with those of the preceding 4 years