Stop Maryland from Using Birth Control to Manage Deer Populations

Target: Paul A. Peditto, Director of Maryland Wildlife and Heritage Service

Goal: Stop Maryland from using the birth control vaccine, GonaCon, to manage deer populations.

In an effort to control the white-tailed deer population in the state of Maryland, the Director of Maryland Wildlife and Heritage Service, Paul Peditto, announced in 2011 that they would be the first state to approve the regulated use of GonaCon, a birth control vaccine intended for use on wild animals. The Environmental Protection Agency approved the use of GonaCon in 2010 for regulated use on female white-tailed deer over one-year of age. This birth control vaccine is registered as a regulated pesticide and any persons administering it need to be certified pesticide applicators. The vaccine needs to be administered with a hand-held syringe, not a dart, in order to be as precise as possible with this immunocontraceptive–and so that unsuspecting persons and other wildlife do not stumble upon a fully loaded dart while out in the woods. We need to stop Maryland from using this sick and twisted method of attempting to control animal populations (that only a decade of study deems safe). It is a cruel abuse of science and we have no way of knowing what the long-term health effects on deer will be.

An immunocontraceptive is a birth control method which uses the body’s immune system to prevent pregnancy. GonaCon, once injected into a body, stimulates the production of antibodies that bind to the gonadotropin, releasing hormone (GnRh) in the body. GnRh then signals the production of sex hormones. By binding to the GnRh, the antibodies limit GnRh’s ability to release the sex hormones estrogen, progesterone, and testosterone. GonaCon is a multiyear vaccine that, once injected, would leave four out of five female deer infertile for up to five years, or as long as there is a sufficient level of antibody activity present.

Because both the vaccine and the antibodies produced are proteins, once ingested by humans or other wildlife, the vaccine and antibodies should be broken down by stomach acids and enzymes–which is why the USDA stated that there is no known danger associated to humans or other wildlife from eating a deer that has been injected with this vaccine. But 12 years is not enough time to deem this vaccine safe for human consumption. Nor is it enough time to monitor what this vaccine does to deer in the long term, especially since half of this study was spent perfecting the vaccine because the first attempt in 1989 to use PZP as a birth control on animals, leaving the female deer in heat for six months instead of one.

Hormones are vital chemicals that carry information and instructions from one group of cells to another. Estrogen, progesterone, and testosterone are hormones that are not simply “sex regulating” hormones; they carry out many other functions in the body. For example, estrogen helps prevent bone loss and works together with calcium, vitamin D, and other hormones and minerals to build bones. Progesterone plays a role in signaling insulin release and pancreatic function, as well as its use as an anti-inflammatory agent which regulates immune response. Testosterone promotes growth of muscle mass as well as bone density. What happens when we limit the production of these hormones in deer for up to five years? What will happen during natural evolution to the one deer out of five that was not effected by the vaccine? Are we just manipulating the deer to evolve to be resistant to this vaccine, thus demanding a stronger vaccine to be created?

We need to demand that Maryland stop the use of this birth control vaccine until sufficient study has been done to provide answers to these questions about the long-term effects of this vaccine on the deer population. Urge the Environmental Protection Agency to conduct further research into the long-term health effects on both humans and animals before granting approval for the use of population manipulating vaccines and pesticides.


Dear Paul A. Peditto, Director of Maryland Wildlife and Heritage Service,

Although the Environmental Protection Agency has approved the use of GonaCon as a birth control vaccine to be used on the white-tailed deer population, we urge you to reconsider the use of this vaccine in Maryland. This vaccine has been approved as the result of only 12 years of study and the long-term health effects on both humans and the deer themselves have not been determined. Without sufficient study, we ask that you halt the practice of using this regulated pesticide as population control for the white-tailed deer in your state.

The health effects of depriving female deer of the essential hormones estrogen, progesterone, and testosterone, which are used in the regulation of insulin release and pancreatic function (progesterone), preventing bone loss (estrogen), and in promoting the growth of muscles (testosterone), for five years while the vaccine stimulates the production of antibodies, have not yet been calculated. Additionally, the vaccine only works on four out of every five deer that are injected, which begs the question: won’t evolution create deer which are immune to the vaccine? In this case, your state will have spent thousands of dollars on buying or making the vaccine, training rangers to become certified pesticide applicators, and then capturing and injecting the deer, only to have them become genetically stronger and more advanced than before.

Please take action to immediately halt the use of this birth control vaccine until further research has been conducted. This vaccine is a short-term solution and a short-sighted abuse of science with a number of paramount possible repercussions.


[Your Name Here]

Photo credit: Becky Gregory via Flickr

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  1. Where have all predators gone?

    They controlled it all so long.

    Where have all pedators gone?

    Killed by hunters every one.

    When will we ever learn?

    When will we ever learn?

  2. doris murmer says:

    This practice has been used in Europe for years without any problems with the animals. Of course, this won’t pass in the USA as we have too many hunters and of course the NRA>

    • To make it clear, I didn’t sign this petition. You’re right and I agree with you that birth control is better than these ongoing mostly cruel hunting methods.

      Just wanted to remind of the fact that all these problems of “overpopulation” are selfmade by human society by disturbing the natural balance just for a pathological pleasure in torturing and killing, greed and profit.

      Thanks Pete Seeger for this wonderful song that’s still as relevant as ever.

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