In 1924, a herd of fourteen American bison was introduced to Catalina Island to provide the backdrop for the production of a film. The herd remained on the Island after filming was complete and since its creation in 1972, the Conservancy has accepted the responsibility of maintaining a healthy herd, while minimizing their impact on the important wildlands habitat of Catalina Island. The Conservancy is also committed to recognizing the free-ranging bison’s significance on Catalina as a heritage herd woven into the Island’s cultural and economic fabric.


A primary consideration in this balance is the size of the herd. Based upon previous scientific study, the Conservancy has determined that the Island can support a healthy bison population of no more than 150 individuals. 

To counter a growing herd size, the Conservancy initiated a contraception program in 2009 as a cost effective and humane approach to maintaining the bison population at sustainable levels. This program has been extremely successful and no additional bison calves have been born since 2013. Contraception halted temporarily in 2015 and the Conservancy hopes to see bison calves on the Island again soon!

Once Conservancy biologists evaluate the number of new calves, the sex of the calves and the number of remaining fertile female bison, they will determine when the contraception program needs to be re-initiated for some or all of the females. Careful monitoring of the bison herd will be required as the young are born and mature.


Catalina Island may be welcoming two more bison to the herd in the future! This thoughtful decision preserves the historical and cultural importance of bison to Catalina Island with a consideration toward the overall health of the Island.

Read the Conservancy's press release about the new additions.

Benefactor Board Member Dr. Tony Michaels provided some context about bison on the Island and the latest decision.  View the video below:

Be aware that the bison on Catalina Island are a free-roaming, undomesticated herd.  As such, they can act out defensively if they feel threatened or provolked.  Interactions with bison may result in serious injury or worse.  



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