ANTARUTIC BENTHOS
161
and Pearse (1962) reported on investigations carried out near White
Island (about 22 km from the summer ice face in McMurdo Sound) and
in the vicinity of the Koettlitz Glacier (about 28 km from the summer
open sea). Collections from White Island were made at depths of 43
and 75 m, and from the Koettlitz Glacier at 40 m. Collections from the
bottom showed a wide range of animals, including Foraminifera,
sponges, hydroids, Alcyonaria, Actiniaria, Nematoda, Ectoprocta, polychaetes, pycnogonids, copepods, isopods, tanaids, gastropods and
echinoids. Specimens of the amphipod genus Orchomenella (probably
plebs Hurley) were caught in thousands in baited traps. The ice in these
areas is thick enough to prevent enough light penetration for diatom
production. Animals presumably must rely on detrital material transported under the ice as a primary source of nutrients. Littlepage and
Pearse noted that a number of very common shallow water McMurdo
Sound animals were missing from these collections, e.g. Limatulu
hodgsoni, Odontaster validus, Lineus corrugatus, and Trematomus
bermcchii. Wohlschlag later (1964, p. 53) records this latter fish species
from beneath the Koettlitz Glacier at Heald Island.
A multi-discipline international project is being discussed under the
title " Ross Shelf Drill-hole Project ", to investigate the effects of ice
cover and isolation from open water on the physical and chemical
properties of the underlying sea water and the associated plant and
animal life. Preliminary investigations along the edge of the ice shelf
were initiated during 1970 at McMurdo Sound.
Four benthic communities in moderate depths at the Haswell
Islands, near Mirny in the Davis Sea, were described by Propp (1970).
1. On rocky ground from 2 to 10 m a community of diatoms, the
sea-star Odontaster validus and the hydroid Tubularia ralphi Bale
occur. The diatoms develop a layer several centimetres thick on the
bottom in spring and summer. The bottom is covered by anchor ice.
Some 20-40 species have been recorded. Total animal biomass reaches
between 20 and 25 g/ma,
2. Between 6 and 26 m a community is dominated by the red alga
Phyllophora antarctica, calcareous algae and the sea urchin Sterechinus
neumyeri. Anchor ice forms to a less extent in this area. The total
number of animal species increases to between 40 and 60. The total
animal biomass is 460 g/ma.
3. Between 25 and 30m the bottom community is characterized
by Alcyonaria. The associated fauna is extremely varied reaching
numbers of 70 or 80 species. Total biomass reaches 1 000 g/ma.
4. I n depths below 30 m a community with the sponges Rossella
racovitzae and Scolymastra joubini, the hydroid Oswaldella antarctica
161
and Pearse (1962) reported on investigations carried out near White
Island (about 22 km from the summer ice face in McMurdo Sound) and
in the vicinity of the Koettlitz Glacier (about 28 km from the summer
open sea). Collections from White Island were made at depths of 43
and 75 m, and from the Koettlitz Glacier at 40 m. Collections from the
bottom showed a wide range of animals, including Foraminifera,
sponges, hydroids, Alcyonaria, Actiniaria, Nematoda, Ectoprocta, polychaetes, pycnogonids, copepods, isopods, tanaids, gastropods and
echinoids. Specimens of the amphipod genus Orchomenella (probably
plebs Hurley) were caught in thousands in baited traps. The ice in these
areas is thick enough to prevent enough light penetration for diatom
production. Animals presumably must rely on detrital material transported under the ice as a primary source of nutrients. Littlepage and
Pearse noted that a number of very common shallow water McMurdo
Sound animals were missing from these collections, e.g. Limatulu
hodgsoni, Odontaster validus, Lineus corrugatus, and Trematomus
bermcchii. Wohlschlag later (1964, p. 53) records this latter fish species
from beneath the Koettlitz Glacier at Heald Island.
A multi-discipline international project is being discussed under the
title " Ross Shelf Drill-hole Project ", to investigate the effects of ice
cover and isolation from open water on the physical and chemical
properties of the underlying sea water and the associated plant and
animal life. Preliminary investigations along the edge of the ice shelf
were initiated during 1970 at McMurdo Sound.
Four benthic communities in moderate depths at the Haswell
Islands, near Mirny in the Davis Sea, were described by Propp (1970).
1. On rocky ground from 2 to 10 m a community of diatoms, the
sea-star Odontaster validus and the hydroid Tubularia ralphi Bale
occur. The diatoms develop a layer several centimetres thick on the
bottom in spring and summer. The bottom is covered by anchor ice.
Some 20-40 species have been recorded. Total animal biomass reaches
between 20 and 25 g/ma,
2. Between 6 and 26 m a community is dominated by the red alga
Phyllophora antarctica, calcareous algae and the sea urchin Sterechinus
neumyeri. Anchor ice forms to a less extent in this area. The total
number of animal species increases to between 40 and 60. The total
animal biomass is 460 g/ma.
3. Between 25 and 30m the bottom community is characterized
by Alcyonaria. The associated fauna is extremely varied reaching
numbers of 70 or 80 species. Total biomass reaches 1 000 g/ma.
4. I n depths below 30 m a community with the sponges Rossella
racovitzae and Scolymastra joubini, the hydroid Oswaldella antarctica