ARCAS Administrative Structure

Board of Directors

Julio Piedra Santa, President

Julio is a Guatemalan engineer and businessman, who has been on the ARCAS board for over 15 years. He owns one of the largest publishing companies in Guatemala. He is passionate about environmental education, and with ARCAS, developed the “Education is Fun” series on sea turtles, mangroves, endangered species and other themes.

Roberto A. Monterroso, Vice President

Roberto is a Guatemalan dentist with more than 40 years of practice. In addition to being a dentist, he is an avid astronomer, soccer referee, and birdwatcher, and, of course, environmentalist. He is a founding member of ARCAS and held the presidency of the board for more than 24 years.

Juan Francisco García, Secretary

Juan Francisco, better known as “Junior”, is a Guatemalan lawyer who has filled important positions at CONAP and at the Environment Ministry and provides invaluable legal and political advice to ARCAS in its government relations. He joined the ARCAS board in 2019.

Jairo Rodriguez, Treasurer

Jairo is a certified public accountant who worked 25 years at the Central Bank of Guatemala, and gives ARCAS much-appreciated advice in financial management. He is passionate about saving the wildlife of Guatemala, and joined the ARCAS board in 2021.

Rodrigo Llarena, Vocal I

Rodrigo is a mechatronic engineer, with a passion for renewable energy and biodiversity conservation. He joined the ARCAS board in 2019

Michael Bostelmann, Vocal II

Michael is a German businessman who has lived in Guatemala since 1976. Always interested in environmental issues, he served on the board of the local Audubon Society chapter in the 90s. He is a Rotarian, is an important local donor to ARCAS and joined its board in 2019.



  • Miriam Monterroso, Executive Director
  • Colum Muccio, Development Director
  • Luisa Maria Ortiz, Administrative Director
  • Ena Elizabeth Yanes, Bookkeeping
  • Juan Carlos de la Rosa Lucero, Logistical coordinator
  • Julissa Carrillo, Social Media Manager
  • Michaela Mogollon-Weisz, Public Relations


  • Sofia Méndez, Director, ARCAS/Hawaii
  • Mynor Sandoval, Sub-Director ARCAS/Hawaii
  • Manuel Galindo, Sea Turtle and Yellow-naped Amazon project extensionist
  • Mario Crespo, Park Guard (CONAP)
  • Osmundo Cuellar, Park Guard (CONAP)
  • Alex Garcia, Park Guard (ARCAS)
  • Mayra Gálvez, Cook


  • Fernando Martínez, Director
  • Alejandro Morales, Sub-director
  • Oda Ericastilla, Education coordinator
  • Anna Bryant, Biology coordinator
  • Johana Sac, Assistant veterinarian
  • José María Bol, Park guard/Animal care
  • Melvin Álvarez, Park guard/Animal care
  • Cesar Bol, Park guard/Animal care
  • Jorge Chi, Park guard/Animal care
  • Aroldo Suchite, Park guard/Animal care
  • María Guerra, Visitor attention
  • Sindy Mas, Visitor attention
  • Natividad Tiul, Cook

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