Re: Kermadec/Herald Petrel

To: "Birding-Aus (Forum)" <>
Subject: Re: Kermadec/Herald Petrel
From: Chris Corben <>
Date: Sun, 06 Dec 1998 02:51:49 -0800
I would note that the white primary shafts are not always easy to see on
Kermadec. I think Rod Gardner is quite correct in suggesting that they will
be harder to see in a bird with its wings sharply angled, partly because the
effect of white shafts is greatly enhanced when white on the inner webs of
the primaries shows through, and this won't happen when the wings are held
closed up. The same effect can be seen in Jaegers (Skuas, whatever).

Also, how obvious the primary shafts are depends very much on the light. I
once watched a Kermadec for several minutes before being able to get the
slightest indication of white on the primary shafts, because the bird was
partly backlit. As soon as the angle between bird and sun exceeded 90
degrees, the white shafts became obvious.

In my experience, there is nothing unusual about a Kermadec showing white
extending inwards along the median coverts, though not all have it (the
greater coverts are basically the same color as the secondaries). Typically
the white under the primaries shows as a larger patch than on Solanders,
because it extends further out along the outermost primaries. I would expect
that Kermadec would most often show a larger patch than either Solanders or
Herald, though maybe someone with more experience of Herald could comment on

When flying in low winds, Kermadec looks rather odd for a Pterodroma, with a
somewhat more Shearwater-like flight, broader, straighter wings than a
Solanders and a tail which looks too small, both short and narrow. But in a
stronger wind, it can arc up much higher and with the wings more angled it
looks more like a real Pterodroma.

Chris Corben
PO Box 2323
Rohnert Park
CA 94927-2323

<Prev in Thread] Current Thread [Next in Thread>

The University of NSW School of Computer and Engineering takes no responsibility for the contents of this archive. It is purely a compilation of material sent by many people to the birding-aus mailing list. It has not been checked for accuracy nor its content verified in any way. If you wish to get material removed from the archive or have other queries about the archive e-mail Andrew Taylor at this address: andrewt@cse.unsw.EDU.AU