I think it's pretty well accepted that only breeding Shy have the yellow,
while White-capped and non-breeding Shy don't have it.
On 12 November 2013 14:31, David James <> wrote:
> Sure, those birds all have a hint of yellow which I acknowledged, and I
> think the photos are from January 2010. My point was that the colour is
> seasonal (because it is faded compared with the pre-breeding flush in
> Aug-Sep) so it is likely to completely disappear outside the breeding
> season. What would the bill of adult Shy look like in the middle of a gap
> year between breeding events? My guess is just like adult White-capped. I
> agree that we need more data to confirm these sorts of ideas.
>
> Cheers,
> David James
> Sydney
> ==============================
>
>
>
> On Tuesday, 12 November 2013 2:16 PM, Jeff Davies <>
> wrote:
>
> I agree Mick,
>
> None of the birds in that link could be confused with steadi, all have
> noticeable yellow at ridge base to bill.
>
> Cheers Jeff.
>
>
>
> -----Original Message-----
> From:
> On Behalf Of Mick
> Roderick
> Sent: Tuesday, 12 November 2013 1:50 PM
> To: David James; Birding Aus
> Cc: Roger McGovern
> Subject: Re: [Birding-Aus] shy v White-capped Albatross
>
> Thanks David,
>
> The images of the birds on the link you provide still show some yellow
> flush
> though and more than one would ever expect from a White-capped as you
> suggest...so they are not ambiguous. It is those birds that have 'zero'
> yellow on the base of the culminicorn that present the ID problem. I wonder
> how many adult Shy's have this yellow flush during the period Aug-Oct and
> if
> perhaps this could be used to at least make a closer judgement on an adult
> Shy-type lacking any yellow observed in mid-NSW waters during that time as
> being more likely a White-capped?
> Your observations in your trans-Tasman travels David are relevant too.
> Where does the line "...as foraging ranges of breeding birds do not appear
> to overlap" (re: steadi / cauta) in Onley and Scofield stem from does
> anyone
> know? This would be another clue that could contribute to helping get close
> to an ID on adult birds at certain times of the year if the information is
> reliable.
>
> The "fresh juvenile test" seems to make a lot of sense, even if it isn't
> backed up by hard science. I like Christine's suggestion of us being
> 'citizen scientists' out there on pelagics and I'm sure you agree to some
> extent Nikolas! ;-) Of course, this is further confused by the possibility
> of juvy Salvin's Albatrosses as well, which fledge at the same time as
> Shy's (e.g. the candidate Salvin's off W'gong 13th Aug 2011 discussed on
> SOSSA). How many juvenile birds called in the past as Salvin's may have
> been
> juv White-capped? The discussions on the SOSSA threads show that it is not
> a
> straight forward ID issue again and I'm not sure for how long the 'messy
> leading edge' has been used as feature to pick a young Salvin's.
>
> Mick
>
>
>
> On Tuesday, 12 November 2013 9:11 AM, David James <>
> wrote:
>
> Nice summary of the complicated issue of identifying Shy (cauta) albatross
> from Tasmania versus White-capped (steadi) albatross from Auckland
> Islands at sea by Mick and Nikolas. I was looking closely at all the
> Shy-types on Saturday's Sydney pelagic, trying to unravel this puzzle.
>
> Firstly, I counted 6 different juveniles that were all White-capped in my
> opinion. Chicks of Shy fledge in April whereas chicks of white-capped
> fledge
> in August (Heather & Robertson 2000). Off Sydney we see few juvenile
> shy-types until August, but in August and September we see large numbers of
> fresh plumaged (i.e. newly fledged) juveniles that must be White-capped.
> They are also more grey-headed on average than juvenile Shy. It is possible
> to track the different White-capped and Shy cohorts as their plumage begins
> to wear and moult. By October the White-capped are a little worn, but not
> yet moulting. And by Nov 11th the 2013 cohort of White-capped were
> moderately worn but still not moulting. On a Sydney pelagic in Oct this
> year (a private charter) there were some very worn and moulting juveniles
> that would be Shy rather than White-capped, but none like that in
> November.
>
> The adults are more problematical as Mick and Nikolas noted already. There
> were 4 adults on the Nov 11th pelagic. None of these had any trace of
> yellow
> at the base of the upper mandible (culminicorn). Nikolas documents
> that shy-types seen by him during Eagle-hawk Neck pelagics always show a
> bright yellow base to the culminicorn, and he assumes that they are Shy
> from
> the nearby Mewstone and Pedra Branca colonies, as well they may be. Nikolas
> and Mick posed the question in different ways, can adult Shy from Tas lack
> the yellow culmicorn base. The answer is definitely yes. My old NPIAW
> "Seabirds of Australia" (Lindsey 1986) has a photos of many Shy at the
> colony on Albatross Island in which I can't see any yellow, but the photo
> is
> poor. A quick search of the internet, however, returns unambiguous photos
> of
> Shy at the breeding grounds showing only a faint hint of yellow culminicorn
> base, e.g.
>
> http://www.anaspidesphotography-blog.com/journal/2010/2/14/tasmanian-seabird
> s-field-trip-albatross-post-2.html
>
> This indicates that the yellow base is a seasonal flush, probably at it's
> height during the courtship period in Aug-Oct and already faded by December
> -Jan. So of course, Shy can lack the yellow away from the breeding grounds.
> But can white-capped ever show a trace of yellow? I've not seen any
> evidence of this.
>
> Adult white-capped may be slightly greyer about the face than Shy on
> average, but it varies with age and individually and is seemingly not
> diagnostic. Adult White-capped may have slightly more black at the base of
> the primaries, but again there appears to be lots of variation and some
> overlap.
> White-capped is larger (longer wing and bill) by about 5% on average.
>
> In February and March 2013 I made 6 crossings of the Tasman on cruise ship,
> four of which were NZ from and to Melbourne, i.e via Bass Strait. I would
> expect that in NZ waters the most numerous would be White-capped and the in
> Bass Strait it would be Shy. Unfortunately, I could not see any difference
> in the underwing or bill patterns either side of the Tasman (but admittedly
> a big cruise ship is not ideal because I was too high off the water and
> conditions were often difficult). What is more, the distribution of Shy's
> was pretty much continuous across the Tasman, i.e. there was no point to
> suggest a gap between the 2 ranges. BUT, there are about 75,000 pairs of
> White-capped and only 5,000 pairs of Shy. This suggests that the majority
> of
> adult birds in the mid Tasman will be White-capped and also the majority of
> birds in the north-western edge of the Tasman (i.e. off NSW) will be
> White-capped too.
>
>
> Cheers,
> David James
> Sydney
> ==============================
> ===============================
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