Conversation about fertility control with Brett Hass, retired biologist previously with NSA (part 1)

Don’t let pesticides like Gonacon™, PZP or SpayVac® manage native wild horses to extinction. The Spin Dr.’s and some ignorant horse advocates are pushing fertility control on underpopulated wild horses. Know the truth and expose those spewing the spin.

PM Gonacon Pesticide Fact Sheet

Read the entire Gonacon™ Pesticide Fact Sheet


John Cox: Brett, you’re a retired biologist, previously with the NSA for how many years?

Brett Hass: 46 long years John. We met in Vietnam, when we a lot younger my friend (smiles). We were doing wildlife and vegetation studies in your AO (area of operations). That was my first assignment with the NSA, as a matter of fact.

John Cox: Let’s cut through all of that. What do you think of Gonacon™ and some of the other fertility controls BLM is using?

Brett Hass: As usual, and as government agencies do and BLM and DOI are extremely guilty, they pretend that science guides its wild horse and burro management strategies. So the agencies involved go forth and resolve issues, supposedly, with experimental drugs–in this case GonaCon™. The question is, in reality, does it resolve anything at all, or is it simply to further experimentations with this drug and the wild horses the most expendable of situations currently?

The problem is very obvious, with the first-time use of an experimental drug, they act like children with a new toy–but this toy is extremely dangerous, to not only the horses and actually lead them to extinction, but the environmental consequences are apparently neglected entirely? (shakes his head negatively). . .

But let’s get real, the very absence of science contradicts any time of sound reasoning for its use whatsoever. So once again we have a government agency, using a Nazi-Type experimental fertility drug on horses and other wildlife–without knowing, or even acknowledging for that matter, what the long-term consequences are–or in perception–the problems that will arise in its actual use.

There is no resolution, as I reviewed the population situation and see first hand there is no over-population if wild horses just within the BLM numbers alone; but livestock, that is a completely different matter, in reality.

John Cox: In your appraisal of the information you’ve read, would you, as a tenured Wildlife Biologist for over 50 years, use this drug?

Brett Hass: Absolutely not! There is no pertinent reasoning to use it right now and especially on wild horses or much of anything else for that matter. Our wildlife and environment is simply too important to be so frivolous with such activity, especially an unknown situation, as fertility drugs used in our natural environment. But as you say, ignorance is quite something, and our government seems to portray ignorance quite well, and frankly the only situation they seem to be competent to accomplish.

Much more on this discussion with Brett Hass later . . .


Below is the original PZP Pesticide Fact Sheet before HSUS seems to have lobbied the EPA to make changes to the chemical class. It’s still only approved as a pesticide to manage pests. PZP is made from slaughterhouse pig ovaries mixed with modified freund’s complete adjuvant.

PM PZP Test mares

(American wild horses used in fertility control experiments)

© John Cox, printed with permission

John Cox is a Vietnam Vet, living in the mountains of the Pacific Northwest who writes about the environment. He’s passionate about saving America’s wild horse herds and wolves. 

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Have you read about the Gonacon™ Experiment on the Water Canyon herd and the UNLUCKY 11 orphans? It all started as a PZP proposal and went down the slippery slope. . .  Read about it here: