Jennifer Marohasy

a forum for the discussion of issues concerning the natural environment

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Managing our Rangelands (Part 1)

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I am passionate about Australia’s rangelands. They cover about 75 percent of the land area of this continent – according to a website that I’ve just discovered.
The Australian Burea of Statistics (ABS), from memory, suggests about 60 percent of Australia is rangeland under pastoral lease.

I am not sure how these vast areas should be managed. I know they are changing – always changing.

Some in the rangelands subscribe to a book published by Allan Savoy in 1999 titled ‘Holistic Management’. I can’t get my mind around much of what Savoy writes, but I do think he raises some important issues.

While I have posted some pieces at this blog that promote the use of fire, Savoy has a very different perspective. He suggests,

“The world was not terribly overgrazed before modern humans, despite animal numbers that are unimaginable today, due to the constant movement of large herding herbivores. Constant movement was brought about by one of the defense mechanisms large grazing herbivores developed to coexist with high numbers of pack-hunting and other predators in a functioning whole. Most herding herbivore females do not have horns or other means of defense. Males generally use their horns for dominating other males and defending territory rather than protecting females and young. So to survive, females of herding herbivores seem to have developed similar strategies – drop all young over a very short period to overwhelm predators, and combine in large herds, which predators fear.

What had the bunching into very large herds to do with minimizing overgrazing of plants and maintaining plant and soil health? This is easy to understand if we look at plant physiology research rather than range research, as the Frenchman Andre Voisin (1988) did over 50 years ago.

What Voisin discovered was that overgrazing of plants is a function of time of exposure and re-exposure of plants and not a function of animal numbers. Concentrated herds of grazing animals feeding with their mouths close to the ground, dung and urinate in high concentration and thus are obliged to move off any ground within a short time and not return at least until weathering has cleaned their feed.

No creatures normally will feed on their own feces, or that of closely related species. Such constant movement, involving short periods of plant exposure followed by a longer period during which plant recovery could take place, would have minimized the overgrazing of plants (only individual plants, not whole ranges, can be overgrazed). And in fact this is just what we experience with holistic planned grazing (described in Holistic Management: A New Framework for Decision Making (Savory and Butterfield, 1999), which simulates nature’s grazing of old.

I believe, as we build our knowledge, we will come to understand that just as soil cannot develop without life, so grassland soils could not have developed without grass, and that grass was mostly as animal-dependent as the animals were grass-dependent. Nature only functions in wholes and patterns. With vast numbers of herbivores, as there simply had to be for the world’s grasslands and their soils to have developed, most vegetation would be grazed by year’s end, leaving little combustible material at the time of most frequent lightning.

Today not only is burning by humans more widespread and frequent than probably at any time in history, but I believe lightening fires are more prevalent in grasslands than would have been the case before humans killed off most herbivores. Where rapid biological decay previously prevailed, today we see gradual chemical/physical breakdown providing billions of tons of highly inflammable material over vast areas of rangeland and certain forests in the U.S., Australia and elsewhere. Toward the season of most lightening, much of the land is a tinderbox simply waiting to be ignited. In addition, the more we humans use fire as a tool to maintain grasslands or forests, the more fire-dependent and flammable the vegetation becomes.”

The Land (June 16, 2005)

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I write a fortnightly column for The Land; the NSW Rural Weekly.

Last week I wrote about drought and Jared Diamond and I have got lots of positive and negative feedback.

The Land doesn’t put a lot of stuff on the web, but the piece is up at the IPA website, click on http://www.ipa.org.au/files/news_981.html.

In the same edition of The Land, Michael Thomson made some comment about the new environemnt group that I’m involved with, the Australian Environment Foundation (AEF), a version of the same was published in the Queensland Country Life click on http://qcl.farmonline.com.au/news.asp?editorial_id=62846

Whales & Climate Change

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As Environment Minister Ian Campbell laments the playing of politics at the International Whaling Commission meeting in Ulsan (South Korea) today, I wish we had a better idea how population numbers of the different whale species are fairing – and also the ecosystems they are a part of.

For perhaps two weeks now the Australian media has diligently reported the Minister including while he has traveled the world rallying against whaling, but the average Aussie would still not have much of an idea about their ecology.

There is a theory in a research paper published in 2003 by Alan Springer et al (Proceedings of the National Academy of Sciences of the USA) that commerical whaling has resulted in the decimation of populations of seals, sea lions and sea otters because killer whales have not had enough ‘regular whales’ to feed on. The abstract to this research paper includes:

We propose that decimation of the great whales by post-World War II industrial whaling caused the great whales’ foremost natural predators, killer whales, to begin feeding more intensively on the smaller marine mammals, thus “fishing-down” this element of the marine food web. The timing of these events, information on the abundance, diet, and foraging behavior of both predators and prey, and feasibility analyses based on demographic and energetic modeling are all consistent with this hypothesis.

According to John Whitfield writing in 2003, “The finding points to the importance of whales in the entire ocean ecosystem, and supports the International Whaling Commission’s decision to ban hunting until whales have returned to their original numbers.”

And I wonder, so what was the original number of regular whales? (I would be interested in links/references to estimates of whale population numbers.)

The same article by Whitfield quotes Andrew Trites of the University of British Columbia, Vancouver, suggesting that “It’s a compelling story, but it’s also a flawed one.” Trites believes that climatic shifts, leading to changes in fish populations, are behind the sea mammals’ decline.

What does he mean by this?

I thought of a piece written about the Pacific Decadal Oscillation and salmon that I read sometime ago by Ned Rozell from Geophysical Institute, University of Alaska Fairbanks. It includes:

Flipping through old issues of fishing journals, Steven Hare of the International Pacific Halibut Commission was struck by the correlations he saw between Alaska and Pacific Northwest fisheries. In 1915, a reporter in Pacific Fisherman wrote that Bristol Bay salmon packers returned to port early due to a lack of fish. At the same time, the chinook salmon run up the Columbia River that borders Oregon and Washington was the best in 25 years. In 1939, the Bristol Bay salmon run was touted as “the greatest in history,” while the chinook catch down south was “one of the lowest in the history of the Columbia.”

The salmon disparity occurred again in 1972, then most recently in 1994, when Alaska fisherman broke a record for salmon harvest while Washington and Oregon managers were forced to close the chinook fishery on the Columbia because so few fish were returning. The current woes of Pacific Northwest salmon fishermen are not due to salmon’s preference for a northern life; Alaska and Pacific Northwest salmon rarely mingle, and many are of different species. So why the correlation between good years here, bad years there?

Ocean conditions must affect the fish. That’s the theory of Hare and Nathan Mantua, an atmospheric scientist at the University of Washington. Simply put, the Gulf of Alaska and Bristol Bay since 1977 have been better places for salmon to be than the northern Pacific off the coast of California, Washington and Oregon. In the twenty years before 1977, years when Alaska’s fisheries were struggling, the northern Pacific were the better waters for salmon.

The researchers think the pattern has to do with a climate phenomenon similar to El Nino. Instead of El Nino’s recurrence pattern once every two to five years, the one that may affect salmon has phases that last 20 to 30 years. This Pacific Decadal Oscillation, as the researchers call it, has its strongest effect in the North Pacific Ocean, while El Nino’s more widespread effects originate closer to the equator.”

This is the third in a series of posts on whaling, see also
https://jennifermarohasy.com.dev.internet-thinking.com.au/blog/archives/000653.html (June 10)and
https://jennifermarohasy.com.dev.internet-thinking.com.au/blog/archives/000646.html (June 7)

Running on What?

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Just last month the PM announced the appointment of a taskforce to “examine the latest scientific evidence on the impacts of ethanol and other biofuel use on human health, environmental outcomes and automotive operations” (quote not at above link).

Is Australia lagging behind the rest of the world in promotion and use of alternative fuels?

New York Times Columnist Thomas Friedman suggests that the answer to the US’s dependence on oil imports is powering cars with electricity and ethanol.

Friedman suggests that, “It costs only about $100 a car to make it flex-fuel ready. Brazil hopes to have all its new cars flex-fuel ready by 2008. …if you combined a plug-in hybrid system with a flex-fuel system that burns 80 percent alcohol and 20 percent gasoline, you could end up stretching each gallon of gasoline up to 500 miles.”

With grain a source of ethanol, could our wheat belt produce the energy to power Australia’s cars?

WA grain grower and 2003 Nuffield Scholar, Aaron Edmonds, has suggested that wheat will not be profitable in the future because of the vast amounts of energy required for production – referring to the energy required to produce nitrogenous fertilisers.

Edmonds has written (not at above link) that, “Given this staunch illogical opposition to transgenic crops by a vocal minority and the huge emerging problem of expensive fossil fuels, it is not surprising to hear some amongst the grains industry proclaim that the whole (GM) argument will be won over the issue of energy. After all, you don’t eat diesel. The US soybean industry, over 80% GM, is processing more and more oil to produce biodiesel. New GM soybean varieties are being bred to improve oil qualities to better fuel performance. Government mandates are being set and it is likely that as the crude oil situation unfolds, crop values will be dramatically increased if they can help satisfy our insatiable demand for energy.”

I might make this Part 4 of my ‘GM Food Crops’posts. Part 3 was posted on 14th June.

End of an Era

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The 170-year tradition of grazing cattle in Victoria’s high country is over according to the Victorian Shadow Minister for Agriculture Philip Davis. In a press release last Friday he said, “In one fell swoop, the Bracks Government this afternoon successfully displaced generations of mountain cattlemen and their families, simultaneously erasing an essential part of Australia’s heritage.”

The day before, on Thursday 16th June, I received the following poem from Duane L Langley.

It was dark and cool in the vast of night when God decided now to strike
From within the dense and massive clouds he threw his multiple lightening pike
It hit the ground with blinding speed and sought the tinder bush
The searing heat completed it’s feat and the flames headed North with a push

The stockman astride his well worn saddle saw this display of might
The sparks they flew from his horse’s shoe as he pounded down through the night
He knew at once that he must ride hard to his mates at camp below
At the camp he reined in hard and fast, with “fire!” being his only bellow

The stockmen knew what they had to do as they climbed their mountain steeds
They raced as a group on back to the coop where the cattle had had their last feed
Two thousand head were soon being led to a two mile wide burnt scree
For it was hear that the land had been burnt as a plan for needs be the animals can flee

With the smoke and the sparks filling the air from the South the cattle were again on the move
For the flames were high on the ever glowing sky, but the cattlemen were now in a groove
They cracked their whips with lightening speed and drove their charges to flee
By mornings light by way of their flight they were all in the lea of the scree

For here the grass was green and lush and fire was stopped in it’s tracks
The cattle were safe and horses relieved as the mountain men alighted their backs
All around wildlife roamed, safe from the wild red steer
Thanks to man and his managing hand, the fire was no longer a fear

2003 came another lightening spree, but the cattlemen were no where to be found
The wildlife headed again to the scree where safety and sanctuary abound
But a sign here stood from a greenie hood that lambasted the Mountain man caste
Wilderness area is now proclaimed for this spot so damaged in the past

As the animals read with a feeling of dread, the sign from modern man
They mourned the day that had passed their way, of the man with the management plan
They hunkered down, too tired to hop, knowing that all was lost
Their last thoughts as they burnt to death, where’s the Mountain man, oh! what cost