Here are some ideas for your volunteering holiday ecotourism arrangements - I have picked these out as being suitably ecotourism related

Try volunteering with Animals .:. Ecovolunteers Peru .:. Ecologia Peru Manu - where you can volunteer with Animals, Travel Agency Atalaya, focuses primarily on offering trips to the jungle of Manu, with the aim to understand and protect this forest which offers us, if you come as eco-volunteers, and volunteering to care out flora and fauna of Manu - peru

.......... volunteering holidays ecotourism ..........

Consider a conservation project on a private game reserve in South Africa where you also take a Game Warden training course. Consider your adventure holiday in Ghana on a worthwhile volunteer project.

.......... volunteering holidays ecotourism ..........

Live and work with one of the communities on the beautiful Miraflor Nature Reserve in Nicaragua. By teaching English you could make a valuable contribution to this coffee growing region's conservation & revitalisation programmes in areas such as eco-tourism, youth development and organic farming. Demand for English is high - it enables them to share their special way of life and hospitality with all visitors and enhances young people's skills.

.......... volunteering holidays ecotourism ..........

Work as part of a structured team on pioneering international projects. With projects all over the world you can join expeditions as diverse as Rainforest Expeditions in the Amazon, Wildlife Research Expeditions in Africa and Marine Research Expeditions in Mexico.

.......... volunteering holidays ecotourism ..........

Join a Nepal volunteer organization that has been formed to address the health and educational needs of the Nepalese people. The organization's activities include fundraising, upgrading medical and educational capabilities and creating opportunities for volunteerism. Be a volunteer with a customised program that enables you to make an important contribution to the people of Nepal, while gaining an in-depth experience of the Nepali language and culture. The INFO organisation provides training and then places volunteers in communities and schools across Nepal where they may be involved with English teaching, environmental awareness, developing income generating programmes, health care education or assist in orphanages, children's homes etc.

.......... volunteering holidays ecotourism ..........

Try adventure sailing holidays for able-bodied and disabled people. The JST is a UK based charity that aims to promote the integration of able bodied and disabled people through adventure sailing holidays. The JST welcomes people from all over the world onto its two specially designed tall ships, the Lord Nelson and Tenacious.

.......... volunteering holidays ecotourism ..........

Working ecotourism volunteering holidays in National Trust locations in England, Wales and Northern Ireland. These include historic buildings as well as countryside, coastal, woodland and farm locations. Many different types of holiday aimed at a wide variety of interests and age groups.

.......... volunteering holidays ecotourism ..........

The Pattaya Orphanage in Pattaya, Thailand, provides a loving home, residential care and education for 180 orphans, up to 100 street children, 220 deaf or blind children and 200 disabled young people. Opportunities for gap year / working holidays teaching English and jungle trekking charity expeditions.

.......... volunteering holidays ecotourism ..........

Raleigh International is a youth development charity set up to inspire people from all backgrounds and nationalities to discover their full potential by working together on challenging environmental and community projects around the world. The training concentrates on personal development, cultural awareness, global issues and preparing people for expedition life.

.......... volunteering holidays ecotourism ..........

Dynamic marine ecotourism volunteering positions available in Madagascar, researching threatened coral reefs ecosystems.

more details of the above here and here