From Field and Study: Aberrant Plumage in Western Australian Seabirds

2012·1.1 MB·English

by  Kevin Coate

FROM FIELD AND STUDY
Aberrant Plumage in Western over the island. Clustered along
Australian Seabirds - Aberrant the shoreline were many almost
plumage in seabirds on islands fledged juveniles.
off the Western Australian coast
2. On 30 July 2004 at Adele Island
is rarely reported. Over many off the Kimberley coast about 100
years of visiting seabird breeding
km north of Cape Leveque, 1
islands 1 have recorded three
photographed an oddly
instances, (1) an albino Brown plumaged Brown Booby likely to
Booby Sula leucogaster; (2) a Brown be leucistic (Johnstone, R. pers.
Booby showing leucistic or
com.). The bird was a fully fledged
schizochroism plumage; and (3) a juvenile capable of flying a short
leucistic Lesser Noddy A nous
distance. The bill, legs and feet
tenuirostris. I provide photo¬ had a pinkish tinge and where
graphs and details of them.
the normal plumage of an adult
1. On a long range excursion Brown Booby is dark brown, in
along the Kimberley coast in this instance there was a barely
perceptible faint light-fawn wash.
August and September 2006
with the Western Australian In photographs several of the
Naturalist’ Club, a visit was made primary wing feathers appear
with a light chestnut tinge, but
to the Lacepede Islands - a group
of four important seabird and this may have been due to the
turtle breeding islands lying light. The eye ring was pink and
the iris of the eye was blue
about 30 km off the mainland
instead of being yellow or olive.
about 120 km north of Broome.
While observing Brown Boobies 3. On 3 December 1989 during
on Middle Island on 4 September filming for the documentary
2006 an adult albino Brown “Wilderness Regained” on the
Booby was seen flying from the Abrolhos Islands about 60 km
breeding area (see photo on off the mid west coast of
cover). The plumage of the Western Australia, an albino
Brown Booby is normally a Lesser Noddy A nous tenuirostris
uniform dark brown apart from chick was found on Wooded
a white lower breast and belly. Island by fellow naturalist Bob
However the plumage of this Goodale. The bird’s entire
bird was entirely white with pale plumage was white with faint
skin around the throat and pink traces of a darker colour on the
eyes. The bill and feet were a pale breast and tips of wings and tail.
greyish colour with a pinkish The flight and tail feathers were
tinge. Although late in the not fully developed. In contrast
season and the breeding cycle to the black bill and dark legs
almost completed, there were usually associated with the
still a number of large fluffy Lesser Noddy, these were of an
chicks and juveniles scattered orange yellow colour as was the
310
Western Australian Naturalists on the Lacepede Islands and an Albino Brown
Booby - September 2006. Photo Jim Everett.
Aberrant plumage in a juvenile Brown Albino Leucistic Lesser Noddy -
Booby - Adele Island - July 2004. Wooded Island - Abrolhos Islands -
Photo Kevin Coate. December 1989. Photo Kevin Coate.
A normal plumaged Brown
Booby and chick - Lacepede
Islands 1995. Photo Kevin
Coate.
skin around the eye. The eyes very diluted normal colour
had a pinkish tinge and the showing. He is also inclined
partial eye rings above and below toward calling the plumage of
the eye were white. The chick the Brown Booby on Adele Island
was perched with a normal leucistic as well. However the
plumaged adult, presumably a term schizochroistic which
parent, beside a nest in dense covers a variety of plumage
mangroves A vicennia marina abnormalities arising from the
about 2 m from the ground. loss of one or more pigments
could also apply. The term
Ron Johnstone curator of
leucistic is the most commonly
ornithology at the Western Aus¬
used.
tralian Museum, describes the
plumage of the Lesser Noddy as All three birds appeared to be
being leucistic as there is some healthy and in good condition.
KEVIN COATE, 11 Peak View,
Canning Vale, W.A. 6155
312