Rosa María fled Bolivia during the military dictatorship of the 1970s. Studying in the United States, she gained a clearer idea of how national parks can be used to protect an area. She returned to Bolivia permantly in 1983, and began travelling – by foot, mule and balsa raft – to the remote villages and settlements in the region where she had spent her childhood, seeking support from the indigenous residents for a park. In most cases, it was the first time anybody from the outside had sought their opinion.

For years, Rosa María lobbied the Bolivian government to create a park, armed with three years of her own research on how people lived and used the land, censuses, resource maps, hydrology reports, signed petitions, a management plan, and detailed maps that outlined proposed boundaries for the park. Finally, in September 1995, her efforts paid off:  the president of Bolivia signed legislation that established Madidi National Park.