Great suggestions folks. A couple of examples. Not all that many
observations of Blue-winged Parrots in Aug/Sept but lots in April/May. The
same for Gang-gang Cockatoo. I am still fumbling around with Budgerigar
and Cockatiel to find more of a concrete pattern with those. But even so
might I suggest that there are larger flocks milling about in April/May
rather than Aug/Sept?
Thanks to you folks I am beginning to think the following:
1. More parrots are breeding so less visible
2. More wonderful Aussie folks are out and about looking at and recording
their activities and posting the info on E-bird.
Open to other suggestions but I think I am on to something here.
Thanks so much!
Don
On Mon, Dec 18, 2017 at 8:31 PM, Martin Butterfield <>
wrote:
> Taking Sonja's point a step further, another possibility is that a lot of
> birds die over Winter.
>
> When I lived in the Eastern US someone authoritative expressed this in the
> following terms (not rigorous but I think the concept works) :
>
> 1. At the start of a breeding season there are x birds in the US.
> 2. Each pair of them rears on average 2 young (which is another 'x').
> 3. Thus at the end of Summer there are 2x birds.
> 4. However by the start of the next breeding season there are only x
> birds again.
> 5. Why isn't the US knee-deep in dead birds?
>
> The answer offered to the final question is that a lot of them don't make
> it across the Gulf of Mexico! The timing of point 3 in Australia would be
> April-May and the timing of point 4 is pretty much September-October.
>
> Martin Butterfield
> http://franmart.blogspot.com.au/
>
> On 19 December 2017 at 15:15, Sonja Ross <> wrote:
>
>> Hi Don,
>>
>> One reason in Victoria is that September and October tend to be our
>> wettest months so birders may possibly spend less time out birding. It
>> could also be that if the birds are breeding in our spring, at least for
>> part of the time, one of a pair could be sitting one eggs.
>>
>> Another could be that April is often Easter when people are often out
>> camping and birding. Successful breeding would also show up in increased
>> numbers then before winter.
>>
>> Sonja
>>
>> On 19 December 2017 at 13:38, Donald G. Kimball <>
>> wrote:
>>
>>> Sorry Martin but are you suggesting there should be more parrot sightings
>>> in Sept/Oct? I thought there were more records and birds present in
>>> April/May. Perhaps I need to scrutinize my findings more. Thanks for
>>> your
>>> imput mate!
>>>
>>> Don
>>>
>>> On Mon, Dec 18, 2017 at 1:37 PM, Martin Butterfield <
>>> >
>>> wrote:
>>>
>>> > Donald
>>> >
>>> > Are you adjusting for the total number of checklists submitted? If
>>> there
>>> > are more lists in Apr/May than Sep/Oct one would expect more records of
>>> > parrots.
>>> >
>>> > Martin
>>> >
>>> > Martin Butterfield
>>> > http://franmart.blogspot.com.au/
>>> >
>>> > On 19 December 2017 at 07:42, Donald G. Kimball <>
>>> > wrote:
>>> >
>>> >> I use E-bird a good deal like many I suspect. I have noticed a
>>> pattern in
>>> >> parrot data. I looked at aproximately 30 species of parrots in NSW,
>>> VIC,
>>> >> NT and noticed that there are more recordings/sightings for most
>>> species
>>> >> in
>>> >> April/May as opposed to Sept/Oct.
>>> >>
>>> >> I have my own ideas as to why this is so but would love some input
>>> from
>>> >> local Aussies.
>>> >>
>>> >> Thanks very much!
>>> >>
>>> >> Don Kimball
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>>> >>
>>> >
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>>
>
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