Study finds Catalina Island Conservancy contraception program effectively manages bison population

December 18, 2013

AVALON, CA -- The wild bison roaming Catalina Island are a major attraction for the nearly 1 million tourists who visit the Channel Island's most popular destination every year. But managing the number of bison so that the herd remains healthy and doesn't endanger the health of the rest of the Island has been a major challenge for wildlife biologists.

A new study by the Catalina Island Conservancy scientists, published in the December supplement of the Journal of Zoo and Wildlife Medicine, reports that the Conservancy's contraception program proved effective in managing the herd's numbers. Previously, more than two-thirds of the cows delivered calves every year. After receiving the contraceptive, the calving rate dropped to 10.4% in the first year and 3.3% the following year.

The Conservancy's study demonstrated for the first time that this type of contraceptive will work in a wild herd, a finding that can help improve bison management programs throughout the United States.

"The success of the Catalina Island Conservancy's bison contraception program demonstrates the innovative approaches our scientists undertake in fulfilling our commitment to being responsible stewards of the land and the Island's resources," said Ann Muscat, Catalina Island Conservancy president and chief executive officer. "By proving the effectiveness of this humane approach to herd management, this research will be a benefit to bison herds throughout the U.S. It also lays the groundwork for further contraceptive studies in other wild species."

The bison were first brought to the Island in 1924 for a movie. Over the years, they became an iconic symbol of the Island's culture. But with no natural predators, the herd grew to some 600 animals. The Catalina Island Conservancy, which protects 88% of Catalina Island, had previously conducted studies that found the Island could support only about 150 to 200 bison. To control the herd's size, the Conservancy had been periodically conducting roundups and shipping bison to the mainland.

"Shipping the bison to the mainland was costly, and it raised concerns about the stress on the animals during shipment and the expansion of the herd beyond ecologically sustainable numbers between shipments," said Julie King, director of conservation and wildlife management and a co-author of the contraception study. "We launched the contraceptive program because it is a humane and cost-effective solution to managing the herd and protecting the Island's resources."

Beginning in 2009, the Conservancy's scientists injected the female bison with porcine zona pellucida (PZP), a contraceptive that had been used for fertility control in zoos, wild horses and white tail deer. In addition to substantially reducing the number of new calves, the PZP had no apparent effect on pregnant females or their offspring. The Conservancy's scientists continue to study PZP to determine if the female bison can regain their fertility after a period of time without the contraceptive.

"The bison contraception program is a good example of trying to reach a balance with cultural, aesthetic or recreational needs and uses and cost-effective natural resource management to maintain the health of the ecosystem," said John J. Mack, chief conservation and education officer. "Because humans have been living and changing the Island for thousands of years, the Conservancy is always seeking new approaches to ensuring the long-term use and ecological health of Catalina Island."
-end-
The Catalina Island Conservancy was formed in 1972 and is one of California's oldest land trusts. Its mission is to be a responsible steward of its lands through a balance of conservation, education and recreation. The Conservancy protects the magnificent natural and cultural heritage of Santa Catalina Island, stewarding approximately 42,000 acres of land deeded to the Conservancy in 1975, 62 miles of rugged shoreline and more than 80 miles of trails. It operates the Airport in the Sky, Wrigley Memorial & Botanic Garden and two nature centers. Twenty miles from the mainland, the Island is home to more than 60 plant and animal species found nowhere else in the world.

Santa Catalina Island Conservancy

Related Health Articles from Brightsurf:

The mental health impact of pandemics for front line health care staff
New research shows the impact that pandemics have on the mental health of front-line health care staff.

Modifiable health risks linked to more than $730 billion in US health care costs
Modifiable health risks, such as obesity, high blood pressure, and smoking, were linked to over $730 billion in health care spending in the US in 2016, according to a study published in The Lancet Public Health.

New measure of social determinants of health may improve cardiovascular health assessment
The authors of this study developed a single risk score derived from multiple social determinants of health that predicts county-level cardiovascular disease mortality.

BU study: High deductible health plans are widening racial health gaps
The growing Black Lives Matter movement has brought more attention to the myriad structures that reinforce racial inequities, in everything from policing to hiring to maternal mortality.

Electronic health information exchange improves public health disease reporting
Disease tracking is an important area of focus for health departments in the midst of the COVID-19 pandemic.

E-health resource improves men's health behaviours with or without fitness facilities
Men who regularly used a free web resource made significantly more health changes than men who did not, finds a new study from the University of British Columbia and Intensions Consulting.

Mental health outcomes among health care workers during COVID-19 pandemic in Italy
Symptoms of posttraumatic stress disorder, depression, anxiety and insomnia among health care workers in Italy during the COVID-19 pandemic are reported in this observational study.

Mental health of health care workers in china in hospitals with patients with COVID-19
This survey study of almost 1,300 health care workers in China at 34 hospitals equipped with fever clinics or wards for patients with COVID-19 reports on their mental health outcomes, including symptoms of depression, anxiety, insomnia and distress.

Health records pin broad set of health risks on genetic premutation
Researchers from the University of Wisconsin-Madison and Marshfield Clinic have found that there may be a much broader health risk to carriers of the FMR1 premutation, with potentially dozens of clinical conditions that can be ascribed directly to carrying it.

Attitudes about health affect how older adults engage with negative health news
To get older adults to pay attention to important health information, preface it with the good news about their health.

Read More: Health News and Health Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.