Thanks for those extra comments. My start point being my memory of what happened. I add this quote from The GBS Report: Page 57,
in the parrot introductory paragraph “….. there are several records of hybrids of the Eastern and Crimson Rosella but these are not monitored separately in the GBS.”
Thus as at the first 21 years, they were not counted and they were ignored, apart from that comment. Given that Martin now comes up with 69 hybrid observations, it appears
therefore that at some stage after that 21 years, Martin or someone added a code number into the GBS database and may have backdated input of that data, or not. Thus I wonder whether instances from the first 21 years are included in that count or only subsequent
to that year. Martin is actually describing the number of observations, not the number of records of these birds. Thus just my suggestion but I would think almost certainly that the great majority of those 69 observations (not records) are repeat sightings
of the same individual(s) over subsequent weeks of the same year at the same site. (A record being a species at a site on a year - so a record can have from 1 to 52 observations – this word use was derived from database terminology). So a count of records
would surely be closer to the number of individuals over that time.
Just from my site, it would be a very rare week over all the years that does not include both rosella species. That does not mean
they are socialising, although they certainly compete vigorously over possession of the nest box most years.
I suspect Martin meant to type “one possible explanation of the relatively more
common observation of hybrids with Crimsons…….”
From: Martin Butterfield [
Sent: Wednesday, 20 November, 2019 1:59 PM
To: Philip Veerman
Cc: Con Boekel; canberrabirds chatline
Subject: Re: [canberrabirds] Hybrid Crimson x Eastern Rosella
I have looked at the GBS dataset to year 30. There are 65097 records for Crimson Rosella, 46238 records for Easter Rosella and 69 records for the hybrid. Of the 69 hybrid records all have Crimson
Rosella in the same Year/week/site. However 28 of the Year/week/site "records" also have Eastern Rosellas, suggesting that Eastern Rosellas are usually in the area, if not actually hanging around with the hybrid.
I have read the species account in Forshaw "Australian Parrots" and it appears that in most cases a pair of Crimson Rosellas stay together. and both care for the offspring for at least a period
of 3-4 weeks after fledging. It wasn't clear if the same ex-nest care was provided by Easterns. However one possible explanation of the relatively more common observation of hybrids with Easterns could be that the male parent of the hybrds tends to be an
Eastern and the hybrid is then looked after by a pair of Crimsons including the promiscuous female.
On Wed, 20 Nov 2019 at 13:29, Philip Veerman <> wrote:
I agree with you about the hybrid. I see no reason though to suppose (based on plumage - or anything else) that it indicates an aviary bred bird, rather than a wildling hybrid. These hybrids happen often enough
from wild birds, to not evoke captive origin. Not saying it isn't, but (presumably) being a hybrid, then being captive bred or not would not change its appearance.
The other thing of interest is these hybrids seem to always associate with Crimson Rosellas, rather than Eastern Rosellas. I wonder how that happens and if we are missing something here.
Philip
-----Original Message-----
From: Con Boekel [
Sent: Wednesday, 20 November, 2019 11:22 AM
To: canberrabirds chatline
Subject: Hybrid Crimson x Eastern Rosella
This image was taken at the ANBG on 19 November 2019. The hybrid was moving in company with a single adult Crimson Rosella.
I assume that the plumage indicates an aviary bred bird rather than a wildling hybrid. But I am not sure about.
regards
Con
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