Hello Andrew,
You asked, Thu, 13 Mar 2003:
>
> What is the maximum lifespan of Superb Lyrebirds?
>
Len Smith writing of Sherbrooke Superbs in "The Life of the Lyrebird"
(Heinemann, 1988), at page 17, says of lyrebird longevity:
"There are few authentic records on the subject, but it is known that
'Timothy', the bird which occupied the firebreak area from the early 1930s
to the spring of 1953, was 25-26 years old when he died. His successor in
the firebreak, 'Spotty', was 21-22 years old at death. The cause of death is
not known in either case, but the prevalence of foxes in the area suggests
that both birds could well have been victims of this scourge of the forest."
(Len then discusses the early demise of certain banded birds - probably fox
predation.)
He continues:
"The evidence from other sources is less conclusive, but the information
about the lyrebirds which were kept in the London Zoo suggests that a
life-span of thirty-six to forty years might be possible under favourable
conditions. Such conditions no longer exist in the Australian mainland
forests, which are virtually overrun by foxes and feral cats."
It is relevant to note that such favourable 'fox-free' conditions did exist,
and probably still do, for the Superbs in Tasmania. The areas to which
they were introduced or which they have since colonised, are in the south of
the State, with the recent fox records being in the east and north, I think.
(BTW, does anyone know how the fox eradication efforts are going in
Tasmania?)
Authentic records of Superb longevity are few. Records for Albert's are
simply non-existent. There is however one piece of evidence indicating a
similar life-span.
In the O'Reilly's section of Lamington N. P., there is one known individual.
Glen Threlfo, O'Reilly's naturalist has, over many years, gradually got
"George" as he calls him, to accept discreet human observation. No other
male will remain in view, so there is no doubt about his identity.
I first tape-recorded that individual on 30 June, 1984, and in a number of
years since. 1984 was some years before Glen 'tamed' him, but from his
behaviour, the display platforms he used, etc., I feel sure that it is the
same individual. Glen agrees that it is the same individual, and further,
he tells me that Peter O'Reilly (snr) knew him as an individual for a couple
of years before 1984.
Len Smith records that for five banded male Superbs, the age at which they
first acquired a full set of filamentary tail feathers ranged from 6 to 9
years. There are no data for Albert's, but it seems likely that they too
would be slow maturing.
George occupies the best territory in his lek group. It is reasonable to
suggest that he must have been fully mature before he was able to occupy and
defend it against all other males.
George was alive and well last breeding season - winter 2002. Thus I have
known him for 18 years. Add another 2 years that Peter has known him,
brings him up to 20 years, plus however many years it took him to reach
maturity.
So one might reasonable suggest that George is at least 25 years old,
posibly nearly 30, and still going well - I hope. I haven't checked with
Glen since last winter. This would be consistent with Len's figures for
Superbs.
Syd
> From: (Andrew Taylor)
> Date: 14:50:01 +1100
> To: Dean Portelli <>
> Cc:
> Subject: Re: [BIRDING-AUS] Lyrebird Mimicry
>
> On Thu, Mar 13, 2003 at 12:16:25PM +1100, Dean Portelli wrote:
>> .... To illustrate: Superbs introduced to
>> Tasmania (1930-40's) continued to include mimicry of Eastern Whipbirds and
>> Pilotbirds in their song (up to at least the 1980's after which it
>> apparently was barely detectable, 1940-1980 is a period greater than the
>> lifespan of a singing adult male i.e. this provides evidence for ?cultural
>> transmission? of mimicry) but have since been noted to mimic several
> What is the maximum lifespan of Superb Lyrebirds?
> The correlation between weight and longevity in passerines would suggest
> a maximum lifespan of tens of years. They are largely ground dwellers
> which I assume is associated with reduced longevity but this maybe
> counterbalanced by the Tasmanian birds as an introduced species being
> free of some factors which reduce longevity.
>
> Andrew Taylor
>
> Birding-Aus is on the Web at
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>
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to
ted with mating though I have no visual observations to support that.
However, I have suggested a test to show what the situation is. Tape-record
(or simply write notes) to list all the mimicked sounds from all the members
of one lek. If I'm right, they will all have the same suite of mimicked
sounds. Go to it, Dean.
Syd
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