Who Affects Rangeland Health?

The Livestock Probability Map, supplied with other scoping documents for permitted grazing on the Sonoran Desert National Monument, says this about the “limited mobility” of cattle on page 5 (citations omitted):

The location of water and salt play a large role in the movement of cattle across a landscape.  In general, livestock do not travel more than 2 miles from water on flat terrain and no more than 1 mile in rough terrain.  Distance from water and slope are two common variables used to predict livestock distribution in almost every environment.  Furthermore, range condition is generally related to the distance from livestock water points.

And you thought only wild horses and burros were responsible for rangeland impacts near water sources?

What about the last statement ?  How does rangeland health vary with respect to distance from water?  The farther the better?

If that’s true, animals with greater mobility (and lower stocking rates), such as wild horses and wildlife, would be expected to have a smaller impact.

RELATED: Management of Western Rangelands in 2018.

Suggestion for the Big-Name Advocacy Groups

Many of the areas currently set aside for wild horses and burros are managed primarily for cattle and sheep, privately owned of course.

Other areas, where horses and burros were found in 1971, don’t have enough food and water to support them, although other users of public lands seem to do quite well.

Paragraph 1332(c) of the WHB Act says the land will be devoted principally for horses and burros.

CFR 4710.3-2 says “We’ll do that if we feel like it.”

Which viewpoint prevails?

Only four of the areas currently designated for wild horses and burros are managed primarily for them, out of roughly 200 areas so designated (HMAs and WHTs).

Here is the issue in a nutshell:

Can a federal regulation supersede a duly enacted statute?

Can the unelected bureaucracy override the legislative process?

That is for the court to decide.

A ruling in favor of the advocacy groups wouldn’t improve anything: It would only put things back where they should have been in the first place.

After that, the hard work begins.

How to Compute ‘Horses Denied’

Yesterday’s post about wild horses denied a spot on their home range only considered areas currently designated for horses.

What about areas no longer designated?  There are many of them, but let’s take a look at the Caliente Complex in eastern Nevada, which consists of nine former HMAs.

An estimated 39,920 AUMs per year have been diverted to privately owned livestock.

How do you determine the number of horses that the resource could support?

Horses graze twelve months per year, so divide the livestock AUMs by 12.

In this example, 3,327 horses have been denied a place on their home range.

That brings the total in yesterday’s post to 40,000, which accounts for 80% of the horses in off-range holding.

Contraceptives are not the answer.  The problem is public-lands ranching.

PSA 12-07-19

Hypothesis Revisited

This statement appeared on these pages back in November:

The number of wild horses and burros in off-range holding (around 50,000) can be explained by the misappropriation of forage on just a few dozen HMAs.

How’s the theory holding up?

Let’s look at the numbers for the areas reviewed in a series of posts called ‘Short End of Stick’ (refer to sidebar on the right).  All calculations were based on horses and cow/calf pairs, even in areas designated for burros and sheep.

Short End of Stick Calcs-1

In the seventeen areas reviewed so far, 36,692 wild horses have been denied a spot on their home range because of privately owned livestock.  That’s about 73% of the horses in off-range holding.

How many more areas would need to be reviewed to bring the total to 50,000?  If the pattern holds, only about six.  So the theory seems to be correct.

Note that livestock receive 85% of the forage overall, with 15% to the horses—on land set aside for the horses.

If livestock were removed, the total AML (for the 17 areas) could be increased from 6,371 to 43,063.  A warrant for contraceptives can not be found in these data.

Thriving Ecological Balance Rev 2

Assateague Herd Declines in Latest Census

WBOC News of Salisbury, MD reported this morning that the March 2020 survey yielded 21 stallions and 51 mares, for a total of 72, compared to 76 in March of 2019.

One new foal was observed but its sex was not provided.  A few more foals may appear in the coming weeks.

The herd (Maryland side of the island) is subject to humane management practices and has been cited as a paragon of wild horse management by some ‘advocates.’

Assateague Census Chart March 2020-1

The chart tells you that the latest results cannot be produced by a simple random process centered at 50% males / 50% females.  Accordingly, one or more assignable causes should be sought.

Why is the sex ratio skewed in favor or females?  Why do males have a high mortality rate?  Is the management program making things better for the horses or worse?

The upper and lower limits of the chart are computed from basic statistical formulas, where p-bar = .50 and n = 72.

RELATED: New Assateague Foal.