shy v White-capped Albatross

To: Birding Aus <>
Subject: shy v White-capped Albatross
From: David James <>
Date: Mon, 11 Nov 2013 14:11:53 -0800 (PST)
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.

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 

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.   

David James

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