Lawrie
Interesting observations. I can't say that I've seen anything like that.
However, I do have a memory of you identifying a Blackbird call in the
background soundtrack of a play about William Buckley!
Cheers
David
Sent from my iPad
> On 22 Apr 2017, at 10:15 pm, Lawrie Conole <> wrote:
>
> Thanks Philip.
>
> That's where simple abundance measures from a location don't really tell
> the whole story. The relative abundance of resident blackbirds in Tylden is
> the same today as it was yesterday - except that a significant number of
> non local birds moved through and out. If I hadn't been out walking the dog
> I'd be none the wiser!
>
> There are various locations around here that are 100-300m higher in
> altitude (so up towards 1000m). I surmise that any blackbirds that are on
> the move have come from altitude.
>
> Regards
>
> Lawrie
>
>
>> On Sat, 22 Apr 2017 at 21:45, Philip Veerman <> wrote:
>>
>> Abundance of the Common Blackbird is almost constant in Canberra. Minimal
>> change through the year (as from the results of 21 years of our Garden
>> Birds
>> Survey, as in my book). And that variation is entirely explainable by
>> changes in levels of conspicuousness. No suggestion of any regular
>> movements
>> in or out of our region. Similar results from the ACT Bird Atlas. In marked
>> contrast to the many native species that show very strong seasonal or
>> monthly changes in abundance due to migrations.
>>
>> Philip
>>
>> -----Original Message-----
>> From: Birding-Aus On Behalf
>> Of
>> Lawrie Conole
>> Sent: Saturday, 22 April, 2017 1:22 PM
>> To:
>> Subject: [Birding-Aus] Blackbird migratory behaviour in Australia?
>>
>> Hi birders
>>
>> Back in 2004 on Birding-Aus I wrote this:
>>
>> "... /Some musing on that feral pest the Common Blackbird (Turdus
>> merula) in Victoria, Australia ..../
>>
>> /A couple of observations this Autumn have me wondering whether some
>> proportion of the Victorian Blackbird population might be migratory -
>> even if its just the kind of altitudinal migration seen in various
>> indigenous birds here. Let me elaborate .../
>>
>> /At two sites I've visited in the last fortnight, I've come across
>> groups of Blackbirds (about 10 birds in each case) roosting/resting in
>> isolated patches of vegetation in farmland during the day. In one case
>> the patch was a cluster of pines in a vast dry grassy paddock, no
>> understorey - very un-Blackbird-like habitat (Craigieburn, northern
>> Melbourne). The others were laid up in a mess of Spanish Heath (Erica
>> lusitanica) underneath remnant Swamp Gums (Eucalyptus ovata) in farmland
>> (south of Colac, northern Otway Ranges foothills). Both sites were at
>> about 200m above sea level, and perhaps less than 50km from more upland
>> forest (>500m ASL). In both cases they flushed in groups, and didn't
>> give the characteristic Blackbird cackle that usually accompanies such
>> disturbance./
>>
>> /This seems vaguely like migrant behaviour to me. Thrushes like these
>> often migrate at night in their natural range, and lay up in various
>> copses of vegetation during the day. In the Craigieburn example, several
>> migrant Grey Fantails were noted in an adjacent patch in the paddock./
>>
>> /I'd be interested in any comments on this matter. Does anyone live in
>> an upland kind of place with fluctuating Blackbird numbers which might
>> suggest regular short - medium distance movements? Any other similar
>> observations? The 'big picture' data presented in the New Atlas
>> publication are not finely resolved enough to address this question -
>> particularly if only some Blackbirds are migrating/moving/ ...".
>>
>>
>> There wasn't much of a response, and nothing to corroborate my musings.
>> So until today I hadn't thought about it much since. This morning
>> pre-dawn when I went outside briefly (Tylden, central Victoria, ~600m
>> above sea level) there was an unusual amount of Blackbird noise - more
>> than I'd expect from our apparently resident pair. Out walking with the
>> dog a few hours later, around 10am, I saw what could only be Blackbirds
>> migrating. Over a period of about 5 minutes, I estimated about 40
>> Blackbirds passed through in a loose stream, going N/NNE (and therefore
>> down in altitude) - much as you see with Yellow-faced and White-naped
>> Honeyeaters when they're migrating - moving from one copse of trees to
>> another, stopping briefly before heading on. In this case both males and
>> females.
>>
>> So why does it matter? Just a feral pest. It has been frequently stated
>> in the literature that Australian introduced populations of Blackbirds
>> are all sedentary. In their native range some populations are migratory.
>> Does that reflect here then that the source populations are from
>> different populations in Europe with respect to migration, or are local
>> environmental conditions just triggering latent migratory behaviour? I
>> can't help but be interested ...
>>
>> If anyone else sees anything similar this autumn, I'd love to hear from
>> you.
>>
>> regards
>>
>>
>> --
>> address.html
>>
>>
>> <#*dr.-lawrie-conole*>/Dr. Lawrie Conole/
>>
>>
>> Tylden 3444, Victoria
>> Australia
>>
>> lconole[at]gmail.com
>>
>>
>> --
> Dr. Lawrie Conole
> Tylden 3444 Australia
>
> lconole |at| gmail.com
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