Mystery Bird No 3, the answer?

To: "birding-aus" <>
Subject: Mystery Bird No 3, the answer?
From: "Robert Inglis" <>
Date: Thu, 30 Nov 2000 16:00:51 -0800
Hello all,

The response to MB3 has been very gratifying.
As well as very interesting.

I have tried to answer as many of the responses I received but I fear I missed a
couple due to other distractions.

So, what is it?
(Note: The following are my own opinions and have been formulated from personal
observations and my interpretation of text and illustrations from the
publications described elsewhere in this article. Comments from respondents to
the puzzle have sometimes helped me in this. Fair criticism of my comments is

The suggestions were:
Common Tern
Little Tern
Whiskered Tern
White-winged Black Tern
Others were mentioned but only in the context of comparisons and by way of

The most popular suggestion was Little Tern.

Rather than eliminate each candidate one-by-one, I will be daring and scratch
all except one in one fell swoop!

The two other birds in the picture are undoubtedly adult breeding Little Terns.
That is the only tern species in Australia (possibly the world depending on how
Saunders's Tern is classified, a race of Little or a separate species) with that
combination of bill and head/forehead colour/pattern. (That could generate some
Particularly note: yellow bill with black tip; head/forehead pattern and black
line through eye to base of bill.

Given the distortion often created by telephoto lenses, MB3 appears to be the
same size and shape as the other two birds.
This, plus the black bill, the dark shoulder 'smudge' and the fact that it is
with Little Terns suggests it also is:

--- Little Tern but in non-breeding plumage ---

It could be an adult non-breeding but the hint of 'scaling' on the wings and the
slightly different colour could mean it may be a juvenile moulting to a 1st
immature non-breeding.
I would welcome comments on that statement.
Perhaps this could also explain the apparent lack of the black in front of the
eye that is said to be a diagnostic point in this species in non-breeding
The illustrations I have seen of Little Tern seem to show distinctly more black
in front of the eye in adult non-breeding than in 1st imm. non-breeding.

Common Tern, which also has dark shoulder 'smudge' would be much bigger than the
other two birds.

Whiskered Tern is marginally bigger than Little and non-breeding Whiskered lacks
the shoulder 'smudge'.
It is interesting to compare the illustrations of non-breeding Whiskered Terns
in all the Australian field guides with those in HANZAB.
HANZAB's could almost be a different bird!
The beachfront habitat makes Whiskered less likely.

White-winged Black Tern's non-breeding head pattern is distinctive and therefore
rules it out.

Other comments:
Breeding and non-breeding birds together:
It appears that Little Tern flocks in Australia can be made up of birds from two
populations, Asian-breeding population and Australian-breeding population.
Little Tern is recorded as breeding in SE Queensland Aug to Nov.
This picture was taken in March and Little Tern is supposed to moult up to three
times a year (a detailed description of this is given in HANZAB).
So, which of these birds is Australian-breeding and which is Asian-breeding.
In fact, are they from the same or different populations?
I don't know.
Who does?

Saunder's Tern:
Harrison, in 'Seabirds an Identification Guide' says that this tern may be a
race of Little or a separate species; either way it is restricted to the Red Sea
and NW Indian Ocean. It does not appear to be accepted for Australia (noted as
an unlikely record in
RAOU's 'The Taxonomy and Species of Birds of Australia and Its Territories',

Field guides:
For this species Simpson and Day 6th edition is poor (Oh! No! Rocks on the roof
- Pizzey and Knight 1997 is fair except that the bills seem to be rather long;
- Morcombe, 2000, is better than Simpson and Day (More rocks!!)
- Slater 1986.... I think he improved with his illustrations for the same
species in HANZAB.
- Seabirds, Harrison, 1983 (is there an updated version?) is disappointing.
It is interesting how field guides seem to work ok in the field but become
dismally frustrating when really accurate identification is required.

Other books
HANZAB (Handbook of Australian, New Zealand and Antarctic Birds) Vol 3 is the
way to go if you can afford it.
(Not too handy in the field though.)
Shorebirds, National Photographic Index of Australian Wildlife has soon
reasonable photos of terns but not enough of each in varying plumages to be a
real 'gem'.

Interestingly, the last mentioned publication puts terns in amongst the

Finally, apart from HANZAB (which probably will not be in everybody's collection
due to the cost) I don't have what I would call a 'good' book on the terns of
Can anyone recommend a good (Australian) tern book?

As my identification of MB3 is really based on the fact that I took the photo
and was able to identify the bird at the time, I would welcome any constructive
criticisms or suggestions before I add this 'Answer' to my web-site.

Bob Inglis
Woody point SEQld, Australia.
27 deg 15min S; 153 deg 5 min E

Birding-Aus is on the Web at
To unsubscribe from this mailing list, send the message
"unsubscribe birding-aus" (no quotes, no Subject line)

<Prev in Thread] Current Thread [Next in Thread>
  • Mystery Bird No 3, the answer?, Robert Inglis <=

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