Hot air and OBP's

To: Dave Torr <>
Subject: Hot air and OBP's
From: Carl Clifford <>
Date: Wed, 6 Sep 2006 21:09:45 +1000
Don't Forget that these figures are for Migratory birds. Australia does not have the anywhere near the number of birds passing through as the USA has transiting from the North American Palearctic regions to the southern USA and Central and South America, but it would still be an amazing figure.
Carl Clifford

On 06/09/2006, at 8:47 PM, Dave Torr wrote:

Wow - so (excluding cats) say 230m a year - which would scale to around 20m a year in Aus I would guess. Windfarms are totally insignificant overall, but of course different structures would get different types of bird - windows would mainly affect urban birds which tend to be common and/or feral. Pesticides would be more widespread. Windfarms would probably "target" specific species dependant on location of course.

On 06/09/06, Carl Clifford <> wrote:
The US Fish and Wildlife Service has a Fact Sheet on migratory bird mortality which gives estimates of deaths from impacts etc. which are rather astonishing. I quote the lower estimates for the worst causes
of death.
Building window impacts - 97 million
Communications towers -4 to 5 million
Cars - 60 million
Wind turbines - 33 thousand
Pesticides - 72 million
Oil and Wastewater pits - 2 million
Cats - no national figures, but they give estimates for the state of Wisconsin of mortality by rural domestic cats - 39 million These figures are the lower estimates, the upper estimates are up to 10 fold.

I make no further comments on these figures, except that I would be very intersted in seeing extrapolations of them for Australia
Carl Clifford
On Wednesday, September 06, 2006, at 07:07PM, Dave Torr <> wrote:

>I recall an estimate (in Handbook of the Birds of the World - can't recall >the volume) that in the USA alone between 500k and 5m birds a year died in >building collisions, and I would assume that our data would be pro- rata, so
>after adding in roadkills etc I guess that windfarms are a very minor
>Of course we will probably never know whether the birds "saved" through less
>greenhouse gases are more or less than those lost through collisions!
>There is I think too much focus on wind and solar (which are intermittent >technologies) and not enough on energy conservation and storage (needed to >cope with wind and solar) - we need a balanced approach to reduce our impact >on the planet. There are also technologies such as extracting energy from >hot rocks that seem to have a lot of promise (and minimal impact) but have
>little publicity.
>On 06/09/06, Greg <> wrote:
>> Hi Evan,
>> Thanks for your reply. As someone involved in the industry do you have >> access to accurate data on the numbers of birds and bats killed by wind >> farms each year? I appreciate the fact that some impacts can be mitigated >> but still believe that solar would have the least impact on ecosystems.
>> I am strongly anti-nuclear so am not a pro-nuke person opposing wind farms >> from that direction. I just don't want us to replace one technology that >> has an adverse impact on the planet with another that, potentially, can
>> have
>> a major impact. The noise and visual pollution are minor issues compared >> with the potential bird and bat kill impacts. I agree that there are a >> number of other structures and machines (motor vehicles, planes etc.) that
>> kill birds and bats but wind farms are now an additional hazard for
>> migratory birds and bats to deal with. So if we want wind farms we have
>> to
>> be sure that the level of kill is low enough to not adversely impact on
>> populations or whole species.
>> I think that people presenting the argument that it is a choice between
>> coal
>> or wind farms are over-simplifying the issue. There are other viable
>> options.
>> Greg Clancy

<Prev in Thread] Current Thread [Next in Thread>

The University of NSW School of Computer and Engineering takes no responsibility for the contents of this archive. It is purely a compilation of material sent by many people to the birding-aus mailing list. It has not been checked for accuracy nor its content verified in any way. If you wish to get material removed from the archive or have other queries about the archive e-mail Andrew Taylor at this address: andrewt@cse.unsw.EDU.AU