Save the mice!...  

An interesting response to the anti-meat position - at least for Australia.

Published figures suggest that, in Australia, producing wheat and other grains results in:

• at least 25 times more sentient animals being killed per kilogram of useable protein
• more environmental damage, and
• a great deal more animal cruelty than does farming red meat.

How is this possible?
Agriculture to produce wheat, rice and pulses requires clear-felling native vegetation. That act alone results in the deaths of thousands of Australian animals and plants per hectare. Since Europeans arrived on this continent we have lost more than half of Australia’s unique native vegetation, mostly to increase production of monocultures of introduced species for human consumption.
Most of Australia’s arable land is already in use. If more Australians want their nutritional needs to be met by plants, our arable land will need to be even more intensely farmed. This will require a net increase in the use of fertilisers, herbicides, pesticides and other threats to biodiversity and environmental health. Or, if existing laws are changed, more native vegetation could be cleared for agriculture (an area the size of Victoria plus Tasmania would be needed to produce the additional amount of plant-based food required).
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Most cattle slaughtered in Australia feed solely on pasture. This is usually rangelands, which constitute about 70% of the continent.
Grazing occurs on primarily native ecosystems. These have and maintain far higher levels of native biodiversity than croplands. The rangelands can’t be used to produce crops, so production of meat here doesn’t limit production of plant foods. Grazing is the only way humans can get substantial nutrients from 70% of the continent.
In some cases rangelands have been substantially altered to increase the percentage of stock-friendly plants. Grazing can also cause significant damage such as soil loss and erosion. But it doesn’t result in the native ecosystem “blitzkrieg” required to grow crops.
This environmental damage is causing some well-known environmentalists to question their own preconceptions. British environmental advocate George Monbiot, for example, publically converted from vegan to omnivore after reading Simon Fairlie’s expose about meat’s sustainability. And environmental activist Lierre Keith documented the awesome damage to global environments involved in producing plant foods for human consumption.
In Australia we can also meet part of our protein needs using sustainably wild-harvested kangaroo meat. Unlike introduced meat animals, they don’t damage native biodiversity. They are soft-footed, low methane-producing and have relatively low water requirements. They also produce an exceptionally healthy low-fat meat.
In Australia 70% of the beef produced for human consumption comes from animals raised on grazing lands with very little or no grain supplements. At any time, only 2% of Australia’s national herd of cattle are eating grains in feed lots; the other 98% are raised on and feeding on grass. Two-thirds of cattle slaughtered in Australia feed solely on pasture.
To produce protein from grazing beef, cattle are killed. One death delivers (on average, across Australia’s grazing lands) a carcass of about 288 kilograms. This is approximately 68% boneless meat which, at 23% protein equals 45kg of protein per animal killed. This means 2.2 animals killed for each 100kg of useable animal protein produced.
Producing protein from wheat means ploughing pasture land and planting it with seed. Anyone who has sat on a ploughing tractor knows the predatory birds that follow you all day are not there because they have nothing better to do. Ploughing and harvesting kill small mammals, snakes, lizards and other animals in vast numbers. In addition, millions of mice are poisoned in grain storage facilities every year.
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Each area of grain production in Australia has a mouse plague on average every four years, with 500-1000 mice per hectare. Poisoning kills at least 80% of the mice.
At least 100 mice are killed per hectare per year (500/4 × 0.8) to grow grain. Average yields are about 1.4 tonnes of wheat/hectare; 13% of the wheat is useable protein. Therefore, at least 55 sentient animals die to produce 100kg of useable plant protein: 25 times more than for the same amount of rangelands beef. [More]

I was vaguely aware of the problems in Australia due to a lack of predators to control introduced species like the famous bunny problem. But I did not know they were still battling occasional mice population explosions.

These calculations may be of little value to our grain-fed beef industry, but the new research in methane accounting and measurement could be altering even those numbers.

New CSIRO research indicates that the amount of methane emitted from cattle fed on tropical grasses in northern Australia is up to 30 per cent less than previously believed.

Current greenhouse gas accounts indicate that methane from the northern cattle industry contributes about 4.5 per cent of Australia's greenhouse gas emissions

CSIRO research leader Dr Ed Charmley says he hopes the new data might allow current estimates of the industry's contribution to Australia's greenhouse gas emissions to be updated.

"Measurements from cattle in CSIRO's custom-built respiration chambers show that Brahman cattle fed a wide range of tropical grasses emit up to 30 per cent less methane than previously determined," he said.

"While you always have to be cautious in extending lab data to the field and across an industry, we have been able to cross-check our findings with methane detecting laser systems used in the field. [Only a little more]

Again, I can't find anything to match this assertion for corn-fed meat, but as better methods for measurement are developed, perhaps those numbers, too will move us on from the caw-fart presumption of GHG contributions of meat.