Michael,
Off Sydney and Wollongong we find that Wedge-tailed Shearwaters are always the
first to follow the boat when we throw scraps over the side such as suet and
pilchards. On almost all trips off Sydney and Wollongong in the summer months
we will have WTS with us all day. However when there are large concentrations
of small fish on the surface it is a different story. All the shearwaters
including FFS will often stay with the live fish. In tropical waters I have
found that this happens a lot more frequently. In fact it is difficult to
keep anything behind the boat in tropical seas such as those off SE Queensland
and Broome. Personally I don't think there is a difference in behaviour just
a more plentiful supply of preferable natural food i.e small live fish.
Other factors such as birds migrating will come into this though. Birds that
are migrating even short distances will often not take any notice of boats.
Short-tailed Shearwaters and Mottled Petrel etc will often shoot straight past
in numbers.
Best regards
Tony
>To:
>From: Michael Craig <>
>Subject: WTSs and boats
>
>Tony,
>
>I read your report on the pelagic trip from Sydney and was very interested
>by your comment "We had difficulty keeping even Wedge-tailed Shearwaters
>behind the boat" given the experience I have had on pelagic trips off W.A.
>I read in the HANZAB that WTSs generally ignore boats and this is certainly
>my experience from the Houtman Abrolhos where you can fly right through the
>middle of a large feeding flock (1000+) and none of the birds ever pay any
>attention to the boat. This is also my experience off Perth where if you
>stand at the front of the boat you tend to see WTSs whereas if you stand at
>the back of the boat all you see are Flesh-footed Shearwaters. When the
>boat stops all the FFSs come in but never any WTSs although the do sometime
>pass by about 50 m from the boat but never seem to pay much attention. It
>would appear from the Abrolhos experience that it is not the FFSs that are
>driving them away.
>Anyway I was interested in whether there was a difference in behaviour
>between W.A. and N.S.W. birds and was wondering what your experience was
>over east.
>
>Mike Craig
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