Sunday, January 31, 2016

North Dakota study shows wind turbines in native grassland to be bad for birds

Jill Shaffer of the U.S. Geological Survey authored the longest-ever study of the effect of wind turbines on prairie grasslands birds

While we wait with fingers crossed for Saskatchewan Environment Minister Herb Cox to release his decision on the Chaplin Wind Energy project (see other Grass Notes stories here), the case against installing wind energy projects on native grassland is gaining ground.

From Saskatchewan Ministry of Environment's web page on the Chaplin Project

A study released last summer by the United States Geological Survey makes it clear that installing wind turbines in native grassland is bad for the birds--not because birds may fly into the turning blades, but because by avoiding the disturbed areas--roads, gravel pads, the massive turbines--grassland birds are displaced and lose their critical breeding habitat.

Here is a report in the Bismarck Tribune, which describes the study as the longest of its kind. Beginning in 2003, the research compares grassland bird data on three sites of native grassland before and after the installation of wind turbines.

Looking at nine species of birds the researchers found that "seven of [them], including the meadowlark and the bobolink, were displaced from good breeding habitat for the study’s duration."

“New wind energy in prime wildlife habitat can influence the distribution of grassland birds for years after construction, including species whose populations are in serious decline,” the report concludes.

this image from the Bismarck Tribune shows one of the three study areas

Thanks to Candace Savage, author of Geography of Blood and Prairie: A Natural History, for alerting me to this report. 

Kevin Van Tighem, well known Alberta conservationist and author, posted this comment online in reference to the study:

"In southern Alberta wind projects have been located too often in large tracts of fescue grassland. The result is to fragment previously continuous habitat, eliminate aerial singers like Sprague's pipit and horned lark, and displace species like long-billed curlew and upland sandpiper that need large tracts of intact prairie. Wind can be green energy, but not when projects are put on the last good tracts of healthy prairie."

Saskatchewan can learn from the mistakes made in North Dakota and Alberta (and on our own native grasslands in the Missouri Coteau) by making sure that from now on, SaskPower and the provincial government will not support or approve wind energy projects on native grassland.

Monday, January 18, 2016

Cattle and the Fate of the Earth, Part II

In last week's post on how livestock grazing will destroy or save the earth, I took a look at the widely ranging field of opinion on climate change and domestic grazing--from the selective truths of Cowspiracy to Tim Flannery to George Monbiot, Hunter Lovins, and Alan Savory.

I ended that post with a promise to provide a bit more insight on Savory's system, which we will get to in short order.

But I want to apologize off the top to anyone who is looking for an unqualified endorsement of Holistic Management (HM). You won't find it here. But neither will you find an out of hand dismissal of it as a viable method of managing grassland. From what I have read on the topic, any management system--continuous, all-season grazing, short-duration intensive grazing, or other forms of rest-rotation--can, in the right hands and with the right stocking rates for the site, produce good results for both beef production and ecological conservation values.

As for the larger claims made by Savory and HM enthusiasts, I am going to lean a little to the skeptic's side of the fence. I am neither a grassland biologist nor a range ecologist nor a rancher. Though I do share some native prairie that we let the neighbour's cattle graze from time to time, I cannot claim any personal experience or knowledge of grazing systems.

I took this photo in the ditch just outside the fence where the cattle in the top photo were grazing--there were lots of lady slippers outside the fence but none inside. Grazing is an important element of grassland management, but there are species that do not do well under intense grazing pressure.

So why am I skeptical of Savory's claims? First, because it just sounds too good to be true and that always makes me suspicious. I can readily believe that in the right landscape with the right soil and climate, a skillful and hard-working grass manager may well increase her production by using HM methods. But I have trouble believing that any system--especially one that has never been proven by independent studies to work on a wide range of grassland eco-types--will sequester as much carbon, and improve water infiltration as Savory claims it will in his Ted talk.

Second, I worry because I do not hear many HM enthusiasts distinguishing between native and non-native grasslands--a vital distinction from a biodiversity conservation perspective. And I worry about people using HM on native grasslands, especially in areas where the land is not terribly productive or resilient.

HM and other methods of "mob grazing" or "short duration grazing," may well be effective for restoring cropland to perennial grasses--if you have the right watering infrastructure and enough labour and skill to make it work the way Neil Dennis has in Saskatchewan. But I have yet to hear of any reports showing that it improves the range condition or biodiversity of native prairie. Until we see at least one independent, peer-reviewed study showing increased biodiversity on native range, increased carbon retention, and improved range condition, I am not sure why we should get enthusiastic about the Savory method and its offspring.

Finally, I am skeptical because people I respect are skeptical. Chris Helzer, whose Prairie Ecologist blog is always even-handed and fair, had this to say about HM and Savory.

Closer to home, I asked Sue Michalsky, Eastend rancher with an MSc in range management, and a director of Ranchers Stewardship Alliance Inc. (RSAI), what she thought of Holistic Management. Here is her response:

"There are several peer-reviewed studies, including a Canadian study with Darcy Henderson as one of the authors, that demonstrate no benefits to biodiversity, carbon storage or even grass productivity associated with high intensity, short duration grazing. To my knowledge (and I watch for these), there are zero peer-reviewed studies that demonstrate a benefit to any of these factors from the use of high intensity, short duration grazing. Despite this lack of evidence, there is an ever-increasing number of people including ranchers, agrologists and environmentalists who are believers. 
What is strange is that the holistic followers view it as a panacea. That is unusual among livestock producers and agrologists. Some of my peers think that holistic grazing may be having a positive effect in severely overgrazed, tame grasslands further south where winter dormancy is not such a huge issue. But not for the reasons that Savory and HMI advertise. Simply because a very short grazing period gives grass a long period of rest that it never had before and tame grasses have been bred to grow aggressively given the opportunity.
The rational viewpoint is that grazing can be good or bad for native grasslands, as can fire. Most of the RSAI ranchers run moderate stocking rates and may rotate pastures, but usually in a low intensity situation. In wet years, they utilize less of the production than they could get away with which likely means that some carbon is sequestered in those years. In successive dry years they may utilize more grass than what is produced, also using stockpiled grass from previous years. However, it is likely that carbon is NOT sequestered in these years and may even be released as root systems die back. There is some research supporting the variability of carbon sequestration on native grasslands and I think it is by Dr. Ed Bork from U of A. 
Historically speaking, it is obvious that grazing and carbon sequestration are not mutually exclusive or grasslands in the northern great plains would not have been able to sequester such huge carbon stores in only a few thousand years. However, the bison did not graze every acre every year. I believe every 8 to 32 years was the estimate for the northern mixed grassland. In addition, it is fallacy that the bison mob grazed. There is a Nature Conservancy (TNC) study (unpublished) that looks at explorer records and aboriginal knowledge to get a handle on this. In most cases, the bison roamed locally in small family units of 20 to 50 head. They did not migrate, but they did move in large numbers away from drought and harsh winters. And possibly away from disturbances such as lots of homesteaders. Under historic conditions, high intensity, short duration grazing rarely occurred. And under those conditions, grasslands stressed by drought or winterkill of grasses did not get grazed, thereby reducing the chances that soil-stored carbon would be released.
I am not saying there are no positive effects from grazing. There are. Grazing stimulates grasses to increase primary production in the same way that exercise builds human muscle and makes us a point. In both cases there is a point beyond which the stress produces negative results. There are many studies that demonstrate increased production under grazing - an S curve model - and even some long term studies which demonstrate that production and therefore economics are better under moderate grazing than either heavy or light grazing / non-use. Moderate grazing stimulates the presence of forbs in a grassland when the climax condition is a few species of old growth grass. Many grassland wildlife species including insects respond positively to moderately grazed habitat.
To make sense of when grazing is good or bad, one need only go back to the range management basics: timing, intensity and duration. Timing in the northern great plains where winter dormancy is an overriding factor means 'at what point during the growing season'. The benefits of deferred grazing are well established. The rule of thumb is that for every day you defer grazing in the spring, you gain 2 - 3 days of grazing in fall or winter. Duration (the length of time) and intensity (the number of animal units per area) are interdependent. This is where Savory is right. He teaches that what is most important is the rest interval. In the northern mixed-grass, there are two relevant measurements. Jim Romo has some research that shows native grasses in SK need more than 400 days of rest to fully recover their root systems from a grazing event. SK Ag keeps referencing some research that I have been meaning to track down that says 'between 50 and 70% of leaf material must be left behind to continue plant growth on native grasslands'. 
In the end, Alan Savory may not be wrong in what he preaches, but preaching is different from practice. The problem is that it is a delicate balancing act to ensure that native rangelands have sufficient rest and recovery before another grazing event and most livestock producers do not have the flexibility or the intricate knowledge required to ensure only ever positive results."

birds like this LeConte's Sparrow need moist tall grasses and sedges. They would not be able to nest in an area levelled by "mob grazing." 

After last week's post many people contacted me with comments on Savory, grazing management and carbon sequestration. One reader recommended a web page and new book on carbon farming--which you can find right here.

Another reader used this web site on grass-fed beef to make the excellent point that if we would keep our livestock out of feedlots and on grass, the results would be better for storing carbon and protecting water.

Thanks to those who wrote in with their thoughts. This is an important discussion if we are going to find ways to make animal agriculture work in a carbon-conscious world where biodiversity and source water protection are public goods that we must all share responsibility for.

Sunday, January 10, 2016

Cattle and the Fate of the Earth, Part I

Depending on who you listen to, livestock are either destroying the planet or saving it. 

For those who argue that livestock are a dead loss to the planet, the primary source of data has always been the 2006 United Nations Food and Agriculture Association report called "Livestock's Long Shadow," which, among other things, blames cattle production for a high proportion of the planet's greenhouse emissions. 

That single document has cast its own long shadow on every subsequent discussion of whether the world would be better off without ruminant livestock. 
from the Cowspiracy website

Then along came Cowspiracy, a popular documentary that stepped up the anti-livestock argument with Indiegogo crowd-funding, a Michael Moore-style narrative, and an all or nothing conclusion that promotes veganism as not merely an environmentally-sustainable lifestyle, but a panacea for our ailing planet.
Cowspiracy, now on Netflix, claims to have used the best science available--or at least the best science supporting their black and white thinking. We can assume that one piece of research they gave a miss was this study published in Nature conducted by a group of scientists working at 40 sites on six continents, including the University of Guelph's Andrew MacDougall. 

The study showed clearly that grassland biodiversity depends upon grazing. In all of the study sites around the world – from the Serengeti to small grasslands in eastern North America -- plant diversity proved to be higher where herbivores, wild or domestic, were able to graze normally.

They also did not check with Tim Flannery, scientist, author of The Weather Makers, and chief commissioner of the Australian Climate Change Commission, who is on record saying that livestock grazing today is a sustainable use of grassland: "If we get the stocking levels right, we get the management techniques right and the management of water and of biodiversity right, I think we can have a very sustainable system of livestock management."

Allan Savory on TED
Meanwhile, early in 2013, holistic grazing guru Allan Savory gave a controversial Ted talk with more than three million views online in which he describes his own panacea for the climate's woes--more grazing. But not just any kind of grazing. Savory is famous for promoting his “holistic range management” brand of grassland management, in which densely packed groups of livestock graze an area for a short duration and then are moved to let it recover—a practice that many livestock producers are adapting under the name “mob grazing.”

In August 2014, however, British pundit and environmentalist George Monbiot, interviewed Savory and dismissed his theories in an article in The Guardian.

Shortly after that, Colorado sustainability promoter Hunter Lovins shot back with her own Guardian op-ed in defence of Savory and “holistic range management”.

OK—let’s stop right there. Following this debate over the past decade has given me a bad case of tennis-spectator neck.

All of the experts make compelling arguments. Even the Cowspiracy film makers have their charm and some of what they say about feedlot agriculture is undeniably true. But they did not look at the wider ecological issues for natural grasslands that scientists and writers like Flannery have explained vis a vis the role livestock plays in replacing absent native grazing animals.

And, as much as I agree with Allan Savory that grazing livestock is an important way for us to restore carbon to our grassland soils, I am not entirely convinced that his system of intensive grazing works everywhere. I may not like the way Monbiot cherry-picks in his critique and dismisses Savory as a quack, but I agree with him on several points about the problems with Savory’s grazing theories. But then I read Hunter Lovins’ defence of Savory and am confused all over again.

That was when I decided to abandon the experts from far away and look for a local one. In part II of “Cattle and the Fate of the Earth”, I ask Saskatchewan rancher, conservationist, and biologist Sue Mihalsky for her thoughts on Savory and his holistic range management system.

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