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September 19th

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🗓2018 statistics: more than 80 foals born, currently 69 surviving
🗓2019 statistics: more than 100 foals born, currently 83 surviving.
🗓2020: 15 foals born, currently 15 foals surviving.


2020 is the first year of results of our PZP fertility control program: 15 foals as opposed to the expected 130 foals we would have had without birth control.
The herd was growing exponentially and many horses would have had to be removed, because there is only limited space for them. It is this reduction of the growth rate that affords the entire herd their continued freedom.
Additional benefits we are seeing:
*The mares are in much better condition this year than last year. (unpregnant)
* The mares have remained with their family bands and all of the foals are strong and appear to be looked after better.
* All foals are surviving, which is a surprising side effect.
* PZP is safe for pregnant mares and lactating mares: all foals were born out of mares that were treated while pregnant.
* We have darted over 600 treatments to over 200 mares and have never missed the correct spot on the mare’s hindquarters.
* No horse has ever been injured or died.
* 29 abscesses have been noted of which 27 were small and 2 were large. This is less than 5% out of 600 treatments, and the abscesses always resolve very fast.
* Unfortunate incidents of dead births, mares that die during labor, and mares under 2 that foal, have been prevented also.
* Next year we are expecting fewer than 10 foals and the natural death rate will start exceeding the birthrate from there on.


The average lifespan of a Salt River wild horse is 21 years. Each year the number of Salt River wild horses will be evaluated and the genetic viability taken into account.


We are reducing the population gradually and humanely, as opposed to removals, which we believe are inhumane and unfeasible as well as ineffective in the long run.


This program is a result of an intergovernmental agreement (IGA) between the Forest Service and the Arizona Department of Agriculture (AZDA) and the contract and cooperation between AZDA and SRWHMG.

We are very proud of our certified darters and our record keeping administrators.

Thank you for your support for our important work. SRWHMG.


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