• Share to Facebook
    • Twitter
    • Email
    • Print
  • Alt text hereDownload PDF

July 9, 2012

HSI Releases Report on Success of Immunocontraception in African Elephant Populations

Humane method of birth control manages growth rates

Humane Society International

  • In South Africa, elephant population growth needs to be controlled humanely. Icarus Images/iStockphoto

Durban, South Africa — Humane Society International released a new report that recaps 12 years of exciting and conclusive research into the field application of an immunocontraceptive that controls population growth rates of free-ranging African elephants. The report was released on the first day of the International Wildlife Management Congress held in Durban, South Africa.

"After more than a decade of research and practical field application of elephant immunocontraception, we are pleased to present the results in this report," said Andrew Rowan, Ph.D., president and CEO of HSI. "Managers of elephant populations in reserves and parks in Africa will find the information useful, and they can use this non-lethal, science-based, humane and effective alternative to culling as they tackle elephant population growth in a pro-active way."

In question and answer format, the document describes the science behind elephant contraception and its successful use in the management of populations of African elephants in 14 reserves and parks in South Africa.

Using a vaccine that currently treats more than 112 mammals, including deer and wild horse populations in the United States, immunocontraception occurs in female elephants who receive a dose of the protein porcine zona pellucida. PZP is delivered via dart guns and causes no pain or stress. It stimulates an antibody response that blocks sperm penetration into the egg and hence prevents fertilization and pregnancy. In field trials to date, the vaccine has proved to be remarkably effective but females must receive an annual booster dose.

The report, Free-ranging African Elephant Immunocontraception: A new paradigm for elephant management [PDF], was written by elephant immunocontraception experts Dr. Henk Bertschinger, a veterinarian and professor at the University of Pretoria, South Africa; Audrey Delsink Kettles, an African elephant behavioral specialist and field director for HSI in Africa; and JJ van Altena, a wildlife management specialist with Global Supplies Inc. of South Africa.

Among the research findings documented in the report are that:

  • The technique is reversible as females not vaccinated in subsequent years become fertile again. This allows managers flexibility when dealing with different elephant populations.
  • The vaccine is not a hormone and no behavioral abnormalities have been observed in vaccinated females.
  • Males in populations where the breeding females are vaccinated behave normally.
  • Females who are pregnant when vaccinated give birth to normal calves.
  • HSI and its parent affiliate The Humane Society of the United States have funded research and development in African elephant immunocontraception for more than a decade, and HSI continues to fund its application. The report contains firsthand accounts from some of the managers of parks and reserves where the method is being used. Wildlife managers in Africa are dealing with questions surrounding the need to slow the growth of elephant populations, especially in smaller parks and reserves, to prevent loss of biodiversity, ecosystem function and resilience, and harm to human lives or livelihoods.


    Media Contact: Rebecca Basu, 301.258.3152, rbasu@humanesociety.org

    HSI's report on elephant immunocontraception can be read here [PDF]

    Follow HSI on Twitter.

    Humane Society International and its partner organizations together constitute one of the world's largest animal protection organizations—backed by 11 million people. For nearly 20 years, HSI has been fighting for the protection of all animals through advocacy, education, and hands-on programs. Celebrating animals and confronting cruelty worldwide—On the Web at hsi.org

    • Sign Up

      Sign up to receive news and action alerts about helping animals

    • Take Action
    Media Contact List2