I have just had a quick look in HANZAB, where your food questions are answered in some detail. Yes they eat a lot of thistle seeds but also a wider range including
some insects. Does that help control thistles? Well maybe as every seed eaten is not going to grow. It is also possible that seed production by thistles far exceeds what these birds can eat and maybe thistles are limited by other factors more than seed eating
by birds. It is probably by good luck that they do not impact much on native species in that they have favourite foods that are introduced weeds. HANZAB does mention some feeding along with Diamond Firetails and other finches and associating with Flame Robins
but this looks like being not much more than incidental. HANZAB mentions their common flock size and has some reports of flocks of hundreds. They are not a threat in terms of nesting (like Mynas are) because they build their own nest, rather than occupy the
limited available tree hollows. As to whether they are pretty or charming. Well yes and that is why the acclimatization society imported them here. The acclimatization society in the 1860s did not think a lot about the impact of introductions on native species.
As for me describing the particular pair of Goldfinches I had in an aviary in the 1970s as obnoxious, I stand by that but that does not mean they all are or that wild free living Goldfinches are also obnoxious.
Philip
From: John Harris [
Sent: Friday, 19 August, 2016 9:38 AM
To: 'canberra birds'
Subject: Re: [canberrabirds] European Goldfinch
This thread about Goldfinches is quite interesting at many levels. I sort of started it off I think by responding to a goldfinch comment and asking if they were a threat to any native species.
There seems to be more acceptance of goldfinches out there than of starlings and other ferals and part of this may be the tendency to favour pretty birds. What would we think if Common Mynas were blue and yellow with a pretty song? Having said that I found
it thought provoking that the goldfinches feed only(?) on thistles. If they do feed ONLY on an introduced weed, then they are a valuable control species and should be welcome. So do I understand my knowledgable colleagues to be saying that they do NOT compete
and are actually useful?
If that is the case, given the coming moist spring, there should be a lot of thistles and we should see a further increase in goldfinches. Cheers
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