SYDNEY PELAGIC TRIP REPORT - SATURDAY MAY 12, 2012
OVERVIEW
Birders who go out regularly on pelagic trips tend to develop theories which
would explain how conditions are likely to affect the number of birds or
species seen on a particular day. Most of these theories are empirical and
usually turn out to be specious as well, such as "the further we go out
beyond the shelf break, the more species we are likely to see". We have
debunked that one on a few occasions along with any number of theories on
"unseasonably warm water" and "unseasonably cold water", although these
theories do still get a regular run on the Halicat. However, on this trip,
we debunked one of the really strongly held theories which says that, when
it is cold, windy and rough, it may be unpleasant for the birders but you
will always see heaps of birds. We had strong south westerlies all day with
quite an unpleasant short period chop and our total species count was 12,
our lowest for at least two years. This is not to say that it was an
uninteresting day on the water (that is never the case!) as we had short but
good views of a Black-bellied Storm-Petrel, extended views of a pod of
hunting False Killer Whales and a close up view of Australasian Gannets
diving into a bait ball.
Surface water temperatures were a little cooler than they were a month ago
being 18.8degC at Sydney Heads and rising to 19.9degC off the continental
shelf. We departed from Rose Bay at 7.10am and returned at 3.45pm. With a
strong south westerly of 20 - 25knots blowing all day, sea conditions became
more uncomfortable as we headed further east with a 1.5m southerly swell and
an unpleasant 2.0m sea on top of that. As a result of these conditions there
were a few cases of sea sickness on the boat.
TRIP SUMMARY
We headed out of the harbour with a complement of 18 passengers on board and
with David James back at the berley table after his trip to Christmas
Island. With all the shearwaters having left for their winter quarters, it
was difficult to get any great interest in the berley trail as we left the
heads but we did have the strange phenomenon of the Silver Gulls staying
with the boat all the way to Brown's Mountain, the first time that we could
recall this happening. After encountering a small pod of Short-beaked Common
Dolphins just off the heads, we had a fairly quiet ride out to the shelf
break, seeing a few Australasian Gannets, an increasing number of
Black-browed Albatross, a Fluttering Shearwater and a couple of Short-tailed
Shearwaters.
As we reached the continental shelf drop off, we saw our first Providence
Petrel of the day and, surprisingly, we saw very few more during the trip.
We set up a berley slick near Brown's Mountain and soon attracted good
numbers of Black-browed Albatross which were joined by smaller numbers of
Yellow-nosed Albatross. A Sooty Shearwater fed around the boat for a while,
a White-faced Storm-Petrel was seen at some distance and did not linger, and
a Southern Ocean Sunfish (Mola Raysayi) was seen making its way across the
slick. After motoring back up the slick and starting a second drift failed
to attract any new species, we moved inshore by a couple of kilometres and
started another berleying session. Again, the same group of birds seemed to
move to the new location to join us but, in addition, a single Great-winged
Petrel added to the species count.
We then commenced a slow run back to Sydney against the south westerly wind
and almost immediately encountered a 'fregetta' storm-petrel which gave only
brief views before it headed away from the boat. Fortunately, Raja obtained
a very good diagnostic photo showing the bird to be a Black-bellied
Storm-Petrel which avoided the need to show only 'fregetta (sp)' in the trip
report. Probably the most absorbing event of the day was when we encountered
a pod of about 30 False Killer Whales which appeared to be hunting. There
were a few Short-beaked Common Dolphins in the vicinity but it was unclear
whether they were prey or were just associating with False Killers. The last
event of the day was the discovery of a circular, bright red, bait ball
several metres in diameter near to the water surface. A few Australasian
Gannets gave us a close view of them spearing into the bait ball and
catching the long beaked fish. See Raja's photographs at
http://www.adarman.com/Pelagics/2012-May-12-Sydney-Pelagic/22950158_75vHZz#!
i=1844330711&k=5PjzfvQ
Except for those who were seasick, it was a very enjoyable day on the water
with plenty to keep interest levels high. By the way, I have new theory
which goes "When it is cold, windy and rough you see a lot more birds than
on a calm day BUT only when the wind is onshore (i.e. from the eastern
quadrant)......"
BIRD LIST
(Note that the numbers in parentheses represent the maximum number of that
species in view at one time)
Great-winged Petrel 1 (1) gouldi
Providence Petrel 6 (2)
Sooty Shearwater 2 (1)
Short-tailed Shearwater 4 (2)
Fluttering Shearwater 3 (1)
Black-browed Albatross 26 (15) two impavida
Indian Yellow-nosed Albatross 3 (2)
White-faced Storm-Petrel 1 (1)
Black-bellied Storm-Petrel 1 (1)
Australasian Gannet 17 (6)
Silver Gull 90 (50)
Crested Tern 7 (2)
OTHER
Short-beaked Common Dolphin 8
False Killer Whale 30
Southern Ocean Sunfish 1
The next Sydney pelagic trip will be on Saturday 9 June 2012 departing
Mosman Ferry Wharf at 6.45am and Rose Bay Ferry Wharf at 7.00am. Call Hal at
0411 311 236 to make a booking.
Cheers
Roger McGovern
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