An interesting discussion on cats and their impact on the environment. Many years ago I too owned a cat – I was outvoted by 3 other family members – and it was a “birder”. It originally belonged to the people next door who have a terrible records with cats and dogs. We started to feed it and, well the rest is history. It was de-sexed which was the only smart thing the neighbours did. Unless people are registered breeders (especially for show animals) I suggest that all cats and dogs should be de-sexed and a VERY big fine be imposed on owners who do not comply with this “law”. There are too may irresponsible breeders and owners out there.
I agree with David on the use of bells on cats. We had two bells and as David says the cat learned very quickly how to move without making them tinkle. I did threaten to put Big Ben on the cat but couldn’t find anything big enough.
Just out of curiosity I will run a small poll to see what people think is the worst predator – Dingo/feral dog, fox or cat (either feral or “house cat”). If I get enough replies I will give the result of the poll. The species listed are in no particular order other than biggest to smallest.
From: David Rees [
Sent: Friday, 29 August 2014 10:46 AM
To: Harold Schranz
Cc: Linda Beveridge; Canberra Birds
Subject: Re: [canberrabirds] How Many Birds Are Killed By Wind, Solar, Oil, And Coal?
re threats to birds and other wildlife
Think we need to be careful re energy sources, we are all at fault with our cars, need for gas, electricity and the like. I would rather see more solar, algal diesel plants etc.etc. in this sunny country even if a few birds are killed than the alternative - coal, fossil oil, oil shale etc.etc. In Canberra we don't have to face the reality of those industries on a daily basis so we get a bit negative when anyone builds anything - such as a solar farm - the one down on the Monaro probably has less impact on the environment than the DFO and actually will provide something useful.
Re cats - I think their impact on birds is over-done in Australia (unlike NZ), except for sea-bird and wader colonies and birds (and small mammals) already made critically rare by other means - mainly direct human - and where they have a significant effect on population recovery. Impact on other creatures, such as small reptiles is probably much greater, and under worked. The Forde/Bonner test could provide data for impact on suburban birds relative to suburbs nearby where no such controls are in place. Would be interesting reading, my bet is that little difference will be seen to populations of species usually found in suburbs in terms of species diversity and density, though birds will get seen to be taken. Wonder about the skink populations though? But then there are currawongs and collisions with cars etc. etc. - i.e. we live in a dynamic environment. Yes, some blue wrens which now live at my place probably get eaten by local cats, however the only reason they are there is that gardens (mine certainly does) now provide them cover and, in spite of predation, they thrive. They were unlikely have been here in the middle of a open sheep paddock that was here 10 years ago. In other words its dynamic. None of like seeing a blue wren eaten by a domestic cat - but that act in isolation may make little difference to the outcome for the population in a Canberra suburb relative to all the other things going on.
I do support the containment policy there as it will reduce number of prowling animals in Mulligans Flat and it improves animal welfare. Disclosure - I own two desexed, chipped, rescued moggies from the RSPCA which are contained even though I live in a Gungahlin suburb where they don't need to be, Currently they are both setting, one each side, watching me pen this email - one of the many reasons why folk have them.
Re cat bells - cans learn how to move silently - I've got one (ex feral kitten) who is a master, bells and all. Would love to know what sound frequency the 'sonar beeper' is expected to work at for birds - given that cats have highly attuned high frequency hearing - for the hunting of mice and the like.
On Wed, Aug 27, 2014 at 4:23 PM, Harold Schranz <> wrote:
"... the Australian Wildlife Conservancy (AWC), which runs private conservation reserves across the nation, released a report in December which estimated the impact of the 5-18 million feral cats on native species such as bilbies and numbats.
Each cat takes 5-30 animals a night, says the AWC, so (using a conservative population estimate of 15 million) they conclude that a minimum of 75 million native animals are killed daily. In a country struggling to conserve its unique fauna, the scale of this figure should not be underestimated."
"Across the Tasman in New Zealand it is birds rather than mammals that have suffered, many of them flightless ground-dwellers. There's the lamentable story of the Stephens Island wren, one of only three flightless songbirds ever known. It was discovered by lighthouse keeper David Lyall in 1894, only to be hunted to extinction by his pet cat and a number of others shortly after."
So while foxes are too a problem, the cat problem, especially in urban areas bordering green space is very significant. No doubt this is why newer suburbs such as Forde and Bonner bordering Mulligans Flat Nature Reserve etc have the Domestic Animals (Cat Containment) Amendment Act (passed into law in 2005) which requires residents in Forde and nearby Bonner to keep any cats indoors or in an outdoor enclosure 24 hours per day."
As the above article states: all "Cats should also wear a collar with a bell, or, even better, a sonar beeper that produces high-pitched tones, which doesn't bother cats, but alerts birds to their presence." It would be interesting to study how effective a measure that is!
On 27 August 2014 14:11, Linda Beveridge <m("bigpond.net.au","gkljbev1");" target="_blank">> wrote:
Thank you for these references, Harold.
... and cats don't seem to kill as many as natural life cycle, natural predators and foxes....
From: Harold Schranz [mailto:m("gmail.com","harold.schranz");" target="_blank">]
Sent: Wednesday, 27 August 2014 12:13 PM
To: m("canberrabirds.org.au","canberrabirds");" target="_blank">
Subject: [canberrabirds] How Many Birds Are Killed By Wind, Solar, Oil, And Coal?
Hi Bird Folk
I came across a USA Study on "How Many Birds Are Killed By Wind, Solar, Oil, And Coal?" which is partially related to the recent August thread in m("canberrabirds.org.au","canberrabirds");" target="_blank"> on the "Potential impact on birds by large solar plants that concentrate the sun's rays".