Park Service Shares Results of Assateague Pony Census

There were 21 males and 57 females in the herd this month, according to a report posted today by WMDT-47 in Salisbury, MD.  Sounds about right, what’s the problem?

Well, the proportion of males seems low.  Alternatively, the proportion of females seems high.

The expected proportion of males is .50.  Ditto for females.  But those are properties of herds that are indefinitely large.

For herds of 78 animals, the observed proportions should fall within calculated limits, namely, .50 plus or minus an amount attributable to random variation.

Using p-chart limits, with n = 78 and p = .5, the proportion of males (or females) in the herd should fall between .33 and .67.  The observed proportion of males is 21 / 78 = .27, which is assignably low.  The observed proportion of females is 57 / 78 = .73, which is assignably high.

What is happening to the Assateague ponies?  A special cause should be sought.

Bands of free-roaming stallions might be bad for tourism so maybe they are the subject of an outplacement program.

Could it be that the fertility control program is screwing up the herd by interfering with natural breeding patterns?  Why would mortality favor males?

What might this portend for other herds where PZP is administered?

RELATED: Baby Boom Next Year on Assateague Island?

USFS Considers Increase to Big Summit AML

The Forest Service has tried to keep number of horses at Big Summit WHT between 55 and 65 according to a management plan established in 1975.  Today the population is around 150.

Advocates say the herd should contain at least 150 animals for genetic viability.

The territory sits between a grazing allotment to the east and highway 26 to the west so others will want the herd maintained at its historic level.

Big_Summit_WHT_Map-1

Refer to this report dated 11/18/18 by The Bulletin of Bend, OR.  The WHT covers 27,300 acres east of Prineville, OR in the Ochoco National Forest.

Baby Boom Next Year on Assateague Island?

NPS has been darting mares with PZP for several years to reduce the number of wild horses on the barrier island but the herd is now at the low end of the desired population range so the effort was suspended.

Biologists are now testing their poop to determine how many mares are pregnant, which will help them predict the size of next year’s foal crop.  Refer to this story, posted today, by the Maryland Coast Dispatch.

BLM to Gather Silver King Horses After Thanksgiving

Helicopters will be used to remove 980 ‘excess’ wild horses from the Silver King HMA, beginning 11/26/18, according to a BLM news release issued today.  The roundup will be open to public observation.

Captured animals will be taken to the Indian Lakes off-range corrals in Fallon, NV, where they will be checked by a veterinarian and prepared for adoption.  Given that the system has been flooded with 12,000 wild horses and burros removed from western rangelands in 2018, most will end up in segregated long-term holding.  No family, no foals, no legacy.

The HMA covers 575,460 acres and has an AML of 128, for an aimed-at population density of 0.22 horses per thousand acres, almost nothing.  The post-gather population will be 244 horses, according to the announcement.  The HMA is in eastern Nevada.

Silver_King_HMA_Map-1

The stated reason for the roundup is overpopulation.  The real reason may forage losses.

This map, which appears at the BLM page for livestock grazing in Nevada, indicates the HMA is subject to several grazing allotments.

Silver_King_Allotment_Map-2

Three hundred wild horses were pushed off the Eagle HMA, immediately east of Silver King, in September.  Perhaps this roundup will finish the job and clear the way for more livestock in 2019?

Anything for the public-lands ranchers.™

UPDATE: Gather stats and daily reports will be posted to this page.

Forest Service Ends Devil’s Garden Roundup

Helicopters were grounded on 11/08/18, with 932 wild horses shipped from the Devil’s Garden Plateau WHT.  Refer to this USFS news release.  Gather stats were not provided:

  • Number of horses removed from the range
  • Number of horses returned to the range
  • Number of horses injured or killed in the traps
  • Number of horses euthanized and reasons therefor
  • Number of livestock harmed by the operation

Approximately 250 horses will be offered for adoption this weekend, according to a story posted yesterday by the Herald and News of Klamath Falls, OR.  They have probably been hand-picked for the event.

An advocacy group argued that the adoption should be cancelled due to an outbreak of pigeon fever that could spread to domestic horses.

Another 650 horses were taken to the BLM Litchfield Corrals where they will be placed into an adoption program that has been flooded by roughly 12,000 horses and burros already gathered from western rangelands in 2018.

A roundup of similar size is planned for 2019.

RELATED: CBS Covers Roundup at Devil’s Garden WHT.

Rangelands in Southeast Oregon

This map, sourced from the WHB maps page, shows Herd Areas and Herd Management Areas in southeast Oregon.  The HMAs, which are managed for wild horse and burros, have blue borders.  The HAs, which may or may not contain HMAs, have red borders.

Jackies Butte HA includes Jackies Butte HMA plus some additional land to the north that is not managed for WHB.  The Warm Springs HA has the same boundaries as the HMA.  The Diamond Craters HA has no land managed for WHB, although horses and burros were found there when the WHB Act became law (that’s the definition of a HA).

SE_Oregon_HMAs-1

Herd Areas are not managed for horses and burros because they don’t have adequate resources, according to the BLM.  Go to 08:30 in this video.

This map, sourced from Data Basin, shows grazing allotments in the same area.  HMAs from the map above have been added in red.  Allotments are shaded green.

SE_Oregon_Allotments-1

Most of the land in this part of the state is subject to BLM grazing permits.  Same for the HMAs.  Some HMA boundaries coincide with allotment boundaries.  Which came first?

Note that lands outside the HMAs also fall within permitted grazing allotments—lands that can’t support horses and burros.  But they can support cattle and sheep?

Would the situation be any different in Nevada?  Utah?  Wyoming?

If the Wild Horse and Burro Program is not run by ranching interests for the benefit of ranching interests, what would be done differently it was?

RELATED: Population Densities on Western Rangelands.