Eric Woehler, who is on board the Aurora Australis for her 4th Voyage of
research and exploration, has asked me to pass on his reports to
birding-aus. The information is taken from the Australian Antarctic
Division's Web Page at:
http://www.antdiv.gov.au
Some of you will have visited this site already, but for those without
WWW access, here are the reports:
DAY ONE AT SEA
Seabird obs, Jan 20. Despite a medium swell and plenty of rain, we had
a wonderful day today seeing many new species. At times the spray
from the waves reached the bridge windows, 15 metres above the water!
More than 12 hours of continuous observations were made along 150
nautical miles of transect. The greatest number of birds seen were
Short-tailed Shearwaters, with large flocks flying south west-ward.
We also saw Black-browed, Wandering and Grey-headed Albatrosses,
White-chinned, Kerguelen, Barau's and White-headed Petrels,
White-bellied Storm Petrels and prions.
START OF SEABIRD OBSERVATIONS
Well, we are finally underway! After more than a week of delay, we
sailed from Hobart just after 2pm today (Jan 19th). Within half an
hour of departing we saw our first seabird - a dark phase Arctic Skua.
As we sailed down the D'entrecastaux Channel, we saw many Australasian
Gannets, Short-tailed Shearwaters and White-capped Albatrosses. These
three species breed locally and so we saw many birds feeding to take
food back to their chicks. Many of the shearwaters were feeding on
jellyfish at the sea surface. Other birds observed included
Fluttering and Little Shearwaters, Fairy Prions and diving petrels.
All observations on Voyage 4 will be made by Eric Woehler and
Stephanie Zador. We will be counting all birds within a 300m wide
transect, from approximately 0730 until dark every day. When we are
south near the Antarctic continent, and there will be 24 hour
daylight, we will finish observations at 2400 local.
BIRD OBSERVATIONS 21 JAN 96
Sunday morning we awoke to nearly calm conditions and a low swell. At
8am we commenced a CTD (conductivity & temperature with depth) cast to
3000m, that took 3 hours to complete. During the time that the ship
was stationary, we had an amazing assemblage of albatrosses aound the
ship: 4 Wandering Albatrosses (stages 4,5,6 & 7 of Harrison), juvenile
and subadult Grey-headed and Black-browed Albatross and one adult
Sooty Albatross, 13 in total. Also seen during the CTD were several
White-headed Petrels, a giant petrel, White-bellied Storm Petrel and
shearwaters. In all, a remarkable collection of birds within 200m of
the ship that gave many people on board their first look at many of
these Southern Ocean species. After the CTD cast, the weather
deteriorated, and we have been 'enjoying' 5m seas with winds reaching
30 knots (50km/hr). As a result we have seen few birds throughout the
afternoon, with only an occasional albatross, White-headed Petrel and
shearwaters. We expect to reach the Antarctic Convergence sometime
late tomorrow, so it is likely that we will see some
Antarctic-breeding species tomorrow.
BIRD OBSERVATIONS 22 JAN 96
With decreasing seas we were able to spend more time looking at birds
and less time hanging on! Several new species were seen today,
including Antarctic Prions, Kerguelen and Mottled Petrels, Northern
and Southern Giant Petrels and Wilson's Storm Petrels. We also saw
plenty of Black-browed and grey-headed Albatrosses, and White-headed
Petrels. By the evening the clouds had disappeared and we were bathed
in sunshine - a welcome change from the rain and cloud we had
experienced for most of the previous 2 days.
As of 10pm local time, we were at 54S, but had not crossed the Antarctic
Convergence. Surface water temperatures were approximately 5.4C, and
we are expecting to cross the Convergence during the night. Thus
tomorrow we are expecting to see more ANtarctic seabird species, in
addition to the Wilson's Storm Petrel seen today.
BIRD OBSERVATIONS 23 JAN 1996
Bird Observations, 23 Jan 1996 We crossed the Antarctic Convergence
this morning: at 5am the sea surface temperature was 5.5C and by 8am
it was 3.5C. After 4 days we are in Antarctic water! The weather
today was generally fine, but in the afternoon a storm came through,
with 35knot winds and 3m swells.
Birds seen today were predominantly shearwaters. We has originally
expected to see these birds until the Antarctic Convergence, but today
we saw almost 1000 shearwaters south of the Convergence: it is likely
that we will see them all the way to the ice.
Other birds seen included Black-browed Albatrosses, Mottled,
White-chinned and White-headed Petrels and both Northern and Southern
Giant Petrels. A few prions and diving petrels, and an unknown storm
petrel were also seen.
Late in the evening we saw a flock of approximately 250 shearwaters
diving into the water to feed. The birds circled once then flew
straight into the water. We have seen similar behaviour on previous
cruises, but this was the first feeding flock seen on this cruise.
Tonight we are at 58S 123E, and heading southwest-ward towards Davis.
We are far enough south to have long days - it is light from about 6
in the morning until almost 11pm. Soon we will be having 24 hours of
light per day, so the two of us will be busy! The weather forecast
for tomorrow is good, so we will have another full day on the bridge.
Bird Observations, 26 Jan 1996
Well, Australia Day was certainly a special day for birds! The last 2
or 3 days have been dominated by high numbers of shearwaters, with
more than 75% of daily totals being shearwaters. This morning we came
across a large flock of shearwaters on the water, sitting in a long
line that was 2 nautical miles long - measured by the ship's radar.
There were 2000 birds within 300 metres of the ship - our count area -
so if the same density of birds was present for the entire flock,
there were between 25 and 30,000 birds in the flock. Most
importantly, there was krill in the water 35 metres below the surface,
directly under the birds. We probably disturbed the birds just as
they were about to feed. This was the largest flock of shearwaters
that we have encountered so far, but it was the third time we have
seen the shearwaters and krill together. We will be carefully looking
for more such observations for the remainder of the cruise.
Other species seen in the last few days included White- and
Black-bellied Storm Petrels, Antarctic, Cape, Snow and Mottled
Petrels, Northern and Southern Giant Petrels and prions. So far we
have seen more than 35 species in just over a week, so it has been an
excellent voyage so far - and there are still species to be seen.
BIRD OBSERVATIONS, 27 JANUARY TO 3 FEBRUARY
Bird observations in the last week have been limited by resupply
operations at Davis Station, oceanographic work and poor weather.
However, bird observations have been made whenever conditions and
operations allow, and highlights of the last few days include:
Saturday 27 Jan Poor weather with easterly winds, fog and snow
flurries meant few birds were seen by us. Despite the poor
conditions, we saw our first Snow Petrels and Antarctic Petrels. Snow
Petrels are usually seen with 50 - 80 km of the pack ice, so we knew
that the ice was close. However, in the gloom and poor visibility, we
saw only a few large icebergs.
Sunday 28 Jan Approaching Davis in the morning, many on the ship had
their first looks at Adelie Penguins and South Polar Skuas. As we
approached the harbour at Davis, we saw many Adelie Penguins standing
on ice floes and porpoising through the water. With more than half a
million Adelie Penguins in the Davis region, Adelie Penguins are
major predators of krill and fish in the region. One of the aims of
the seabird component of the cruise is to estimate the quantity of
food these penguins eat in the Antarctic summer. South Polar Skuas
are scavenging seabirds, and are very inquisitive. For almost half
an hour we had two skuas flying barely 3 metres above our heads,
looking for food scraps, or perhaps looking at the incoming summer
scientists....
Monday 29 Jan Heading north along the first leg of the survey, we saw
few birds until later in the evening when we entered a region of sea
ice. Associated with the ice were flocks of Snow Petrels, Adelie
Penguins, Antarctic Petrels and Wilsons Storm Petrels. Wilsons Storm
Petrels are the smallest birds found in the Antarctic, and feed by
'walking' along the surface of the water while holding their wings
out, and pecking at food items in the surface layer of the water.
Late in the Antarctic summer these small birds will migrate to the
Northern Hemisphere (as far as California and Japan) to avoid the
Antarctic winter.
Tuesday 30 Jan and Wednesday 31 Jan Oceanographic work prevented much
bird watching, since we do not count birds while the ship is
stationary. We know that several species of seabirds are attracted to
the ship, mainly because they assume we are a fishing vessel, and the
birds may be able to get a meal. Also some birds are inquisitive, and
come to investigate the vessel. In either case, we do not want to
count these birds, as the counts would be exaggerated or inflated by
these birds attracted to the ship. Most of these two days were spent
waiting for the oceanography to finish before more counts could be
made.
Thursday 1 Feb During the survey we saw three large flocks of
Antarctic Petrels roosting on icebergs. The first flock was
approximately 1 km from the ship on a small iceberg, and was estimated
to contain approximately 4000 birds. The second flock was further
from the ship, on a large iceberg 2km from the ship. This flock was
estimated to contain 8000 birds. However, by far the largest flock
was one estimated to contain between 40 and 50,000 birds! We were too
far from the berg to get an accurate count, but the flock was very
large, and we think our estimates are probably lower than the true
number of birds present. On a previous survey in 1993, I had seen an
immense flock of Antarctic Petrels on a large tabular iceberg. We
measured the iceberg by radar, and it was approximately 1km by 1 km
square. Almost 1 quarter of the iceberg was covered by birds - a
flock we estimated to contain 250,000 birds ! An incredible sight.
Friday 2 Feb and Saturday 3 Feb A combination of fog and snow flurries
has shortened the time spent on survey, and much time was also spent
on station conducting oceanographic research. We are still seeing
shearwaters, but not in high numbers. An occasional White-chinned
Petrel and Blue Petrel around the ship has meant that we have birds
with us all the time.
So, after 2 weeks at sea, we have seen more than 30 species and have
counted more than 16000 birds within our 300m survey transect. In the
next message, we will provide a list of species seen, as well as new
sightings and news of our work. The next 2 days will be busy, as we
expect the weather to improve and we are not scheduled to do any
oceanography for that time. So, we hope to survey the birds without
interruption, and who knows what we will see....
Until next time!
BIRD OBSERVATIONS, 04-08 FEBRUARY
A quiet few days, despite our expectations of higher numbers of birds
on the survey legs. Highlights of these five days are given, as well
as a species list of all birds seen so far:
Sunday 04 February Today we saw several flocks of Arctic Terns
roosting on ice floes. These birds are migratory, breeding in the
Northern Hemisphere close to the Arctic Circle (66 degrees North) then
migrate to the Antarctic to avoid the northern winter. These birds
spend almost 8 months a year flying, and only 4 months at the breeding
grounds. We have seen several flocks of Arctic Terns roosting on
icebergs, mixed with Antarctic Petrels and Snow Petrels.
Monday 05 February An unusual day for the Southern Ocean, with flat
seas and no winds. As a consequence we saw few birds, as many
Southern Ocean seabirds rely on wind to minimise their energy
expenditures and maximise the distances travelled. We saw many birds
resting on the water, waiting for the winds to increase. The most
spectacular flock was a group of 25 Light-mantled Sooty Albatrosses
sitting on the water. Large dark birds, with a 2 metre wingspan,
these birds were conspicuous on the flat sea, and were seen by many of
the scientists on board.
Tuesday 06 February Another day of flat seas, no winds and even fewer
seabirds. We saw flocks of shearwaters resting on the water, and
occasionally flying low over the surface in search od food. Most
interesting was the sighting of several Mottled Petrels amongst the
shearwaters. Mottled Petrels nest in New Zealand, and travel south to
the Antarctic pack ice, and also to Alaska: another long-distance
migratory species. We have seen more Mottled Petrels on this cruise
than on any previous cruise.
Wednesday 07 February Little time was spent counting birds as most of
the day was occupied with oceanographic activities. The most note
worthy sighting was that of Snow Petrels 70 nautical miles from the
pack ice. These birds are strongly associated with the pack, and it
is very unusual to see Snow Petrels so far from the ice.
Thursday 08 February Poor weather conditions (snow flurries) and
oceanographic activities prevented much bird work. Currently we are
at 65 South, 93 East, in an area rarely visited. Tomorrow we will
head towards the coast, and it will be interesting to see which birds
we see in this area.
So far, we have seen the following 37 species: Emperor and Adelie
Penguins Wandering, Black-browed, White-capped, Grey-headed, Sooty and
Light-mantled Sooty Albatrosses Southern and Northern Giant Petrels,
Southern Fulmar Antarctic, Cape, Snow, White-headed, Mottled,
Kerguelen, Barau's, Blue and White-chinned Petrels Narrow-billed,
Antarctic, Fulmar and Fairy Prions Short-tailed, Fluttering and Little
Shearwaters Wilson's, Black-bellied and White-bellied Storm Petrels
diving petrels, Australasian Gannets Antarctic and Subantarctic Skuas,
Parasitic and Pomerine Jaegers Arctic Terns
More soon from Aurora Australis!
BIRD OBSERVATIONS, 9 TO 13 FEBRUARY
Friday 9 February An early call at 5am to the bridge was rewarded with
the sight of approximately 1000 Snow Petrels feeding and roosting on
ice within 20 minutes. These all-white birds are essentially confined
to the pack ice region, but are rarely seen in such numbers. We have
seen Snow Petrels feeding before on the cruise, but never in such
numbers. Snow Petrels are surface feeders, flying close to the
water's surface and picking food from the top few cm of the water. An
incredible way to start the day!
Saturday 10 February Another early call to the bridge, this time to
get our first look at the Shackleton Ice Shelf - a large area of ice
attached to the Antarctic that reaches the sea, with water flowing
underneath the ice. We slowly travelled northward along the western
edge of the Shelf, and saw many large icebergs that had formed by
breaking away from the main part of the Shelf. We saw only a few
Adelie Penguins and an occasional South Polar Skua. We stopped
counting while oceanographic experiments were conducted, but generally
we saw ver few birds for the remainder of the day.
Sunday 11 February Sunday was a gloomy and foggy day, travelling east
along a transect to begin the next leg of our investigations. There
was plenty of fog around, and occasional snow flurries, so we saw only
those birds that flew close to the ship - others were lost in the
gloom. The commonest birds we recorded were shearwaters, travelling
westward, presumably to feed.
Monday 12 February Another quiet day, as we headed south towards the
pack ice. Very few birds were seen, and we believe this is because
there was no food in the water for them. At sunset we were treated to
a rare spectacle - a green flash as the sun disappeared over the
horizon. Many people were on the bridge waiting, and were rewarded
with an emerald-green flash as the sun set. Most had their cameras
ready, and we are all hoping that these pictures will come out!
Tuesday 13 February Clearly the best day weather-wise for the voyage
so far. Back in the ice, with clear blue skies and no wind, many
people were out on deck in t-shirts. Today we saw many Emperor
Penguins, as we had passed two breeding colonies within the last 24
hours. Emperor Penguins normally weigh about 25 kg (55 pounds), but
many we saw today were much heavier, approaching 40 to 45kg (90 to 100
pounds)! A heavy bird!! The penguins have been feeding and laying
down a layer of fat to sustain them during their month-long moult.
During the moult, penguins can not swim as they are no longer
protected from the cold water by their feathers. So they stay on the
ice and shed their feathers before returning into the water to regain
the lost body weight. Two of the Emperor Penguins we saw today had
begun their moult.
More again soon from Voyage 4!!
========================================================
I will send further reports as they arrive
Russell Woodford
Birding-aus List Maintainer
|
