Habitat "Guidelines" Without Scientific Support

This post contains a group of letters and documents on the subject of range-practice advice for the Western ranges of Desert Mule Deer.  This advice was given by the Mule Deer Working Group and Texas Parks and Wildlife.

This current range advice, which recommends complete destocking, or low-density set-stocking, is responsible for the decline of our Western ranges.  These are desertifying, i.e. the grasslands and savannahs are shifting to brush and bare ground across the West.

TPWD Mule Deer Habitat Advice

I was surprised to learn at a TPWD mule deer seminar that the way we graze cattle at Circle Ranch harms plants and water function. So I read all the studies on which these conclusions were based and found they did not study what they claimed to study. I wrote this letter to the authors…

Mule Deer Working Group Response to Chris Gill

This is the response I received from Dr. Heffelfinger on behalf of the Authors and Sponsors of Habitat Guidelines for Mule Deer.

Chris Gill’s response to the Mule Deer Working Group regarding Habitat Guidelines for Mule Deer advice against planned grazing.

Rather than send a long, separate response, I decided to try an  interlined response, dealing with these points one at a time.  I hoped that doing it this way would get the authors to focus point-by-point.

Briske et al. Synthesis Paper

In this paper, highly-respected Texas A&M range scientists Dr. David Briske et al. conclude that planned grazing has been disproved, and that low-density set-stocking is the best grazing protocol.  The paper reaches seven basic conclusions:

1.   In spite of overwhelming evidence to the contrary, rotational grazing continues to be promoted as the only viable grazing strategy.

2.    Continuation of costly experiments under conventional protocols will yield little additional information.

3.    Continuous grazing produced better plants in 87% of the studies, compared to rotational grazing.

4.    Animal performance was better under continuous grazing in 92% of the studies compared to rotational.

5.    Several effective strategies exist, but none have the unique properties that makes it more ecologically effective.

6.    Different outcomes are dependent on management.

7.    Advocacy for any form of rotational grazing is based on subjective perception and anecdotal interpretation.

I read Dr. Briske’s studies and found that the studies he relied on in reaching these conclusions had not tested planned grazing.  Instead they tested       what are known as short-duration grazing-rotational systems (SDG’s).  SDG rotational systems are not, and have never been, recommended by Allan Savory.  This error of testing SDG’s instead of planned grazing is commonplace among conventional range scientists, as the exchanges in this section demonstrate.

Chris Gill’s Response to Briske et al. Synthesis Paper

I had already read the Briske paper and realized that it tested Short Duration Grazing systems and not planned grazing.  But when the Authors of Habitat Guidelines for Mule Deer offered it as proof of their conclusions against planned grazing, I wrote Dr. Briske this letter and copied the Authors.  Neither Dr. Briske nor the Authors replied to this letter.

Steve Nelle to Mule Deer Working Group June 2009

Steve Nelle is one of the leading NRCS scientists practicing today.  We tried to get the authors of Habitat Guidelines to visit Circle Ranch and meet with Savory, who journeyed from Zimbabwe for this purpose.I even offered to pay airfare.  None attended.  One author is a TPWD employee who, based in part on the faulty range science of the Heffelfinger conclusions, is the architect of the elk removals discussed on this website.

Chris Gill to Authors & Sponsors of Habitat Guidelines for Mule Deer, Concerning ‘Corrections’ Made in Response to My Letters

In September 2009, I was in Department headquarters in Austin, when I ran into one of the Authors of Habitat Guidelines for Mule Deer.  I asked him to explain the faulty science of the Book, and he responded that the PDF version had been corrected.  I was delighted… until I downloaded and read the ‘new’ version.  There was not a single material change to the book.  The range advice remains the same.  With respect to planned grazing, no scientific evidence is alleged to support the conclusions and recommendations which are identical.  The bibliography continues to list the studies:  the new version does not say these support the conclusion but the reasonable inference from their inclusion is that they do so.  So now, the representations that planned grazing harms plants and water function is offered without support.

This document was amended in 2009.  It is dated 2006, but contains, for example, references to the Briske, et al. paper published in 2008.  Its conclusions are identical to the unamended version.

Richard Teague et al. on Benefits of Planned Grazing

This paper by Richard Teague, Fred Provenza et al. challenges the conclusions of Dr. Briske.

Of Mule Deer and Paradigms

I wrote this for Holistic Management International’s semi-monthly publication In Practice, discussing the Mule Deer Working Group’s unwillingness to amend its conclusions which misstated the scientific basis for their advice against planned grazing.

Doing What Works: Range Magazine

Here is the summary of two years of correspondence with the Mule Deer Working Group, my futile attempt to get them to change the sloppy-science-based range advice which so harms desert habitats and wildlife.  What this shows with respect to the range science on which wildlife practices are based, is 20 wildlife agencies ignoring science in favor of what they already ‘know’.

Posted by Chris Gill

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