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--Apple-Mail-2-380746151 Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Content-Transfer-Encoding: 7bit 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 --Apple-Mail-2-380746151 Content-Type: text/html; charset=US-ASCII Content-Transfer-Encoding: quoted-printable <html><body style=3D"word-wrap: break-word; -webkit-nbsp-mode: space; = -webkit-line-break: after-white-space; "><div><div style=3D"word-wrap: = break-word; -webkit-nbsp-mode: space; -webkit-line-break: = after-white-space; "><div>Hi folks,</div><div><br></div><div>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."</div><div><br></div><div>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.</div><div><br></div><div>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!</div><div><br></div><div>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.</div><div><br></div><div>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