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More on this.
Seeing JAG's comments on my
message (fearing for my fine reputation, as he put it on 22-2-2002), has
inspired me to write down one additional speculation of mine. True I don't know
for certain that what is described for N Qld is this disease but it is a pretty
fair guess.
That speculation of mine being that one of many factors that
just may have contributed to the documented huge increase
in abundance of Sulphur-crested Cockatoos, Crimson Rosellas
and Australian King-Parrots in Canberra over the last 20 years (the larger two
species are susceptible to PBFD, I don't know about Crimson Rosellas, I haven't
seen that), is the decline in incidence in PDFD in Canberra during that time. In
the mid 1980s, many people noticed infected and sick birds all over but there
have been very few reports in recent years. In the same time Eastern Rosellas
and Galahs have remained stable in numbers. Demonstrating a connection is very
difficult.
Philip
-----Original Message-----
From:
Philip A. Veerman <>
To:
Graham <>; birding aus
<>
Date:
Sunday, 24 February 2002 13:42
Subject: [BIRDING-AUS]
Sulphur-crested Cockatoos & PBFD
Re: my previous note. It says that "The
following is a quick summary from Shephard (1994) Aviculture in
Australia." However, I misled you a bit by adding sentences in the
wrong sequence. That book is about captive birds. My statement "It
tends to run in wild populations for a few years then decline" is NOT
derived from that book. It is just an opinion based on my impression of when I
have encountered it in wild populations.
Philip
-----Original Message-----
From:
Philip A. Veerman <>
To:
Graham <>
Date: Friday, 22 February 2002
13:54
Subject: Sulphur-crested Cockatoos
A summary:
What you observe is very likely what is known as
psittacine beak and feather disease (PBFD). It affects parrots (including
cockatoos). I had not heard any suggestion before that it is related to the age
of birds. The following is a quick summary from Shephard (1994) Aviculture
in Australia. He suggests it mostly occurs in young birds, having
been passed on by infection from parents. It is a contagious viral disease with
no cure. It is probably terminal to birds that get severe symptoms, if not due
to direct impacts, then due to impact of loss of feathers or deformed beak or
claws. It tends to run in wild populations for a few years then decline, It is
also characterised by excessive growth and often deformation of the
beak.
Philip
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