Here is an extract (from page 47) of some of the relevant text from my 2006
book: Canberra Birds: A Report on the first 21 years of the Garden Bird
Survey there is more detail of records under individual species. From which
I can update that the Common Starling and House Sparrow have both declined
drastically since then as has the Myna given the very extensive eradication
program we have had here. The Cockatiel is one of the better survivors local
and that is hardly surprising.
Introduced species and escaped or released pet birds
Some other studies have focused on the hypothesis that exotic species are
better adapted to the urban or suburban environment than are native species.
Long (1981) provided a global overview of this issue. Canberra is
extensively built within mainly native woodland (although often exotic
grassy understorey). There are no extensive areas of absence of native
vegetation and most GBS sites comprise Australian and exotic vegetation.
Pryor & Banks (2001) have described the vegetation. All 10 exotic bird
species with ACT populations (Mallard, Rock Dove, Spotted Turtle-Dove,
Skylark, House Sparrow, European Greenfinch, European Goldfinch, Common
Blackbird, Common Starling and Common Myna) were recorded in the GBS.
However as a group, exotic species do not dominate the bird community.
Canberra does not have any introduced species that are not also well
represented in other major cities of eastern Australia. Canberra is also
lacking in large feral populations of: Spotted Turtle-Dove, Eurasian Tree
Sparrow, Nutmeg Mannikin, European Greenfinch, Red-whiskered Bulbul and Song
Thrush that are well established in some other major cities of eastern
Australia (Chapman 1969). The only dominant species, more than 5% of the
bird population (Huhtula & Jarvinen 1977) in Canberra are the Common
Starling, House Sparrow and recently the Common Myna. Of the rest, two more
are ranked within the top 32 most often recorded species (with the next one
at 113). The 21 years results show that the Common Starling and House
Sparrow have been the two most abundant species, though both are in decline.
The Common Myna has shown a dramatic increase in the same time. The increase
in this species is of concern because of its nest competition with other
birds.
There are many exotic and Australian species of (mainly) parrots, pigeons
and finches that have been recorded rarely. These are often pet birds that
have escaped or their progeny. It is clear that the frequency of these birds
in the GBS (Appendix 1) closely matches the relative frequency at which
these species are kept in captivity (Shephard 1994). For example, the
Budgerigar is by far the most common bird pet and has many more GBS records
than any other species whose presence occurs most often as escaped or
released pets. It is also clear that some species survive much better than
others, post release. Escaped native parrots often associate with similar
sized common native species for extended periods. For a few species that
occur in low numbers naturally in the region, as well as being kept captive,
it is difficult to assess the extent to which these occurrences are natural
(Veerman 1991a).
-----Original Message-----
From: Birding-Aus On Behalf Of
Charles Hunter
Sent: Wednesday, 6 January 2016 9:21 AM
To: Birding-aus NEW
Subject: Lost birds!
Hi all,
I was just posting a sighting on Eremaea of a presumed escapee Cockatiel
that I saw in a reserve Coogee in Sydney.
I did a quick search out of interest of "Lost Cockatiels" and was rather
surprised to see the large volumes of "lost birds" on Gumtree.
The link is
here:http://www.gumtree.com.au/s-lost-found/sydney/lost+cockatiel/k0c18437l3
003435
I wonder how many birds (budgies, parrots, etc.) are actually "lost" each
year and which species would actually survive their escape.
Personally I am not a fan of having birds or animals in captivity.
Cheers,Charles Hunter
<HR>
<BR> Birding-Aus mailing list
<BR>
<BR> To change settings or unsubscribe visit:
<BR> http://birding-aus.org/mailman/listinfo/birding-aus_birding-aus.org
</HR>
|
