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New Zealands are required to feed the dogs found in This is a multi-part message in MIME format. ------=_NextPart_000_0009_01CA61EE.3103E510 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable How can you compare a dog eating meat and cereals, which can be linked = to growth on an area of farmland, with a motor vehicle burning = hydrocarbons formed 300 million years ago and built in a modern plant = using electricity ( produced how?) plus plastics, etc..=20 Boy this argument doesn't make sense at all. I noted months ago an article about the Halifax market refurbishing a = building to be a green model. It cost millions. Where do people think = money like that is generated? Most does not come in green manner. So with respect Chris, I have a lot of problems with the calculations = you have provided and with other examples we see of greener living. I'm not a model of such myself - but I try in a modest way. Pete Hope - owner of 2 medium sized dogs and 2 largely housebound cats ( = 3 of the 4 are neutered - the other is very old) PS I do believe the predation arguments made regarding pets=20 ----- Original Message -----=20 From: Christopher Majka=20 To: naturens@chebucto.ns.ca=20 Sent: Tuesday, November 10, 2009 9:47 AM Subject: [NatureNS] How green is your pet? Hi folks, In an article published 23 October 2009 in NewScientist entitled "How = green is your pet?", Kate Ravilious looks at the ecological impact of = pets. The results of her research are fascinating. Part of the article = is based on a recent book by Robert and Brenda Vale at Victoria = University of Wellington in New Zealand, entitled "Time to Eat the Dog: = The real guide to sustainable living." The Vale's analyzed the ingredients of pet food and calculated the = ecological footprints of pets. For example, a medium-sized dog consumes = about 164 kilograms of meat and 95 kilograms of cereals a year. It takes = 0.84 hectares of farmland a year to generate that much food. For a large = dog such as a German shepherd, the ecological footprint is 1.1 hectares. Meanwhile, an SUV (the Vales used a 4.6-litre Toyota Land Cruiser in = their comparison) driven a modest 10,000 kilometres a year, uses 55.1 = gigajoules, which includes the energy required both to fuel and to build = it. One hectare of land can produce approximately 135 gigajoules of = energy per year, so the Land Cruiser's eco-footprint is about 0.41 = hectares, less than half that of a medium-sized dog. So, a large dog has = about 2.5 times the environmental impact of a gas-guzzling SUV! Similar calculations show that the ecological footprint of a cat is = 0.15 hectares (slightly less than that of a VW Golf); a hamster's is = 0.014 hectare; a canary 0.007 hectares; and even a goldfish has a = fin-print of 0.00034 hectares (3.4 square metres), about the same energy = usage as two cellphones. The United States, which tops the list for cat and dog ownership, is = home to over 76 million cats and 61 million dogs. Taking the estimated = cat population of the top 10 cat-owning countries, the Vales calculated = that the land required just to feed these cats is over 400,000 square = kilometres. That's equivalent to 1.5 times the area of New Zealand. A = further five New Zealands are required to feed the dogs found in the top = 10 dog-owning countries! Ravilious also examines other effects of pet ownership. For example, a = recent article (Mammal Review, 2002, volume 33, page 174) indicates that = cats annually kill 188 million wild animals in Great Britain, i.e., = circa 25 birds, mammals, and frogs per cat per year (and surveys in = Australia and the United States have shown similar numbers). Also, cat = excrement is particularly toxic. In California a decline in sea otters = has been linked to a brain disease caused by the parasite, Toxoplasma = gondii. It is found in cat faeces and ends up in rivers due to cat = owners who flush their cat litter down the toilet or allow their cats to = defecate outside. Dolphins and whales have also been affected [this is = from a study by Gloeta Massie and Michael Black presented in 2008 at the = annual meeting of the American Microbiology Society]. Dogs also cause problems by disturbing wildlife in wild areas where = they are allowed to run off-leash. In Australia Peter Banks and Jessica = Bryant of the University of New South Wales (Biology Letters, volume 3, = page 611) showed that areas frequented by dogs had 35 per cent less = avian diversity and 41 per cent fewer birds overall compared to areas = where dogs were not allowed. Studies in Great Britain link the decline = of some species of birds, such as European Nightjar (Caprimulgus = europaeus), to disturbance by dogs (The Ibis, volume 149, page 27). A quick calculation I did from some of the data in the article shows = that the ecological footprint of an average person in Great Britain is = is ~ 7.5 hectares/year. Thus, a large dog would comprises about 15% of = that value. David Mackay, the United Kingdom government's new energy = adviser is quoted as saying, "If a lifestyle choice uses more than 1 per = cent of your energy footprint, then it is worthwhile reflecting on that = choice and seeing what you can do about it." The full NewScientist story is available at: = http://www.newscientist.com/article/mg20427311.600-how-green-is-your-pet.= html Cheers, Chris Christopher Majka 6252 Jubilee Rd., Halifax, Nova Scotia, Canada B3H 2G5 c.majka@ns.sympatico.ca "The further backward you can look, the further forward you can see." = - Winston Churchill ------=_NextPart_000_0009_01CA61EE.3103E510 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META content=3D"text/html; charset=3Diso-8859-1" = http-equiv=3DContent-Type> <META name=3DGENERATOR content=3D"MSHTML 8.00.6001.18852"> <STYLE></STYLE> </HEAD> <BODY=20 style=3D"WORD-WRAP: break-word; -webkit-nbsp-mode: space; = -webkit-line-break: after-white-space"=20 bgColor=3D#ffffff> <DIV><FONT size=3D2 face=3DArial>How can you compare a dog eating meat = and cereals,=20 which can be linked to growth on an area of farmland, with a motor = vehicle=20 burning hydrocarbons formed 300 million years ago and built in a modern = plant=20 using electricity ( produced how?) plus plastics, etc.. = </FONT></DIV> <DIV><FONT size=3D2 face=3DArial></FONT> </DIV> <DIV><FONT size=3D2 face=3DArial>Boy this argument doesn't make sense at = all.</FONT></DIV> <DIV><FONT size=3D2 face=3DArial></FONT> </DIV> <DIV><FONT size=3D2 face=3DArial>I noted months ago an article about t