Jeff makes a really good point about how changes in the environment can
sometimes trigger population explosions of exotic species. The Laughing
Turtledove was introduced into the Perth suburbs at the end of the 19th
Century and, although, its range spread slowly throughout the greater Perth
area over the next 30 years, this species' range and abundance increased
markedly into the South-west Wheatbelt area in the 1930s & early 1940s,
coinciding with increased bulk grain-handling. The Laughing Turtledove and
Barbary Dove belong to the same genus (Streptopelia spp.) and have similar
ecological niches. So if the Laughing Turtledove can suddenly increase its
range and abundance under the right environmental conditions, then I believe
that the Barbary Dove can too. Therefore, I am in favour of controlling the
Barbary Dove population in SA before a potential ecological problem occurs.
Stephen Ambrose
Ryde, NSW
-----Original Message-----
From:
On Behalf Of Jeff Davies
Sent: Friday, 2 October 2009 4:17 PM
To: 'Peter Marsh'; 'birding-aus'
Subject: Barbary Dove
G'day Peter,
I guess my answer to your question is we could accommodate hundreds of
established ferel species in Australia all presenting with "little evidence
of damaging effects" as you describe. But one thing is for certain given
time they will slowly evolve as a better fit to the exotic environment they
find themselves in, some will do it slower than others or just die out, some
will find they are already a good fit and take off like rabbits. There is no
exact time frame for any of this and the experience of a species as an
exotic in one part of the world doesn't necessarily apply elseware, eg.
House Sparrows are finding it hard going in the UK at the moment. There is a
population of Barbary Doves in Los Angeles which is staying put for the
moment, do you suggest we use that as evidence they will never move out of
Adelaide. If Barbary Dove was selectively bred from African Collared Dove
then wild breeding birds under environmental pressure will evolve back to
something similar and have characteristics more suited to Australia actively
selected for, it's anyone's guess how long it would take, but it's a risky
experiment to just sit back and watch played out from the side lines.
Cheers Jeff.
-----Original Message-----
From:
On Behalf Of Peter Marsh
Sent: Thursday, 1 October 2009 6:12 PM
To: birding-aus
Subject: Barbary Dove
Dear Birders,
There are indeed Barbary Dove in the SW suburbs of Adelaide as I saw 2 of
them today in Oaklands Road, Somerton Park.
Can someone outline the reason why this species is considered such a danger
as compared with, say Spotted Dove or Laughing Dove which are both
introduced and appear to do little harm (as far as I know). Birds Australia
and the BIGnet group of bird clubs in NSW are both working on policy
guidelines for dealing with what have been called overabundant or invasive
bird species. In each case there needs to be objective evidence that the
species will cause damage to native animals or plants or to human health
before we go running off trapping, shooting, poisoning or whatever. This
evidence can be local or from overseas. In the case of Canada Geese for
instance there is abundant evidence fron the UK and New Zealand. In the case
of the Common Mynah there is much hysteria but seemingly little scientific
evidence of the damaging effect of this species. By contrast the recent
survey in the Capertee and Holly Parson's work in suburban Sydney show the
inverse correlation between species abundance and Noisy Miner presence but
there seems to be little concern among the public or birders.
Regards
Peter Marsh
==========www.birding-aus.org
birding-aus.blogspot.com
To unsubscribe from this mailing list,
send the message:
unsubscribe
(in the body of the message, with no Subject line)
to:
===========
===============================
www.birding-aus.org
birding-aus.blogspot.com
To unsubscribe from this mailing list,
send the message:
unsubscribe
(in the body of the message, with no Subject line)
to:
===============================
===============================
www.birding-aus.org
birding-aus.blogspot.com
To unsubscribe from this mailing list,
send the message:
unsubscribe
(in the body of the message, with no Subject line)
to:
===============================
|
