In the face of global climate change and coral reef degradation, the Green Fins initiative promotes conservation through sustainable reef-dependent businesses.Climate change is widely heralded as the single greatest threat to coral reefs, frequently responsible for mass ecosystem mortalities through processes such as ocean acidification and coral bleaching. However, the scientific community also recognizes that local-scale impacts have been the primary cause of coral reef degradation during recent decades.
By 2020, the World Tourism Organization predicts that a record 1.4 billion tourists will cross international borders in a single year. Many of these tourists will be divers and snorkelers visiting the world’s most beautiful coral reefs. While this represents a significant economic opportunity, it also carries environmental risk. Irresponsible diver and snorkeler behavior often leads to direct damage to corals. Careless fin kicking causes skeletal damage to corals or breaks them , . Divers or snorkelers may touch corals, leading to tissue abrasion, which makes corals more susceptible to disease and algal overgrowth . Higher levels of coral disease  and lower hard coral cover have been reported on intensively dived reefs , , . Another source of physical damage is boat anchors and chains, resulting in live coral being dislodged, broken, and often killed. Other impacts associated with the marine tourism industry include sewage and chemical discharge, increased marine debris and sedimentation from coastal development. Additionally, divers or snorkelers who harass, touch, or chase marine life will cause them stress, which may interfere with resting, feeding, or breeding and can ultimately lead to death.
Educating the industry in pragmatic marine conservation practices can measurably reduce these anthropogenic impacts. Green Fins is a public-private partnership initiative for environmental stewardship in the marine tourism industry, established by UN Environment and The Reef-World Foundation in 2004. Through Green Fins, more than 500 marine tourism operators have committed, complied with, and shown improvement in 15 areas related to their impacts on the environment and community awareness within major diving destinations across Thailand, Malaysia, Singapore, Indonesia, Philippines, Vietnam, and the Maldives.
A 15-point code of conduct is used to reduce environmental impacts of participating dive and snorkel centers. Performance is evaluated annually using a 330-point system that scores impacts; the lower the score, the lower the impacts the businesses have on coral reefs. Continued participation and Green Fins certification is dependent on centers lowering impact scores from year to year. The system includes criteria to identify high-risk practices above and below the water, offers realistic low-cost alternatives, and is implemented on the ground by resource managers trained and supported by The Reef-World Foundation. A suite of educational materials related to coral reef conservation through sustainable reef tourism is freely available to download from the Green Fins website. In areas where Green Fins is not yet active, these can still be used by individuals, businesses, organizations, and governments to collectively reduce threats to reefs and other marine environments.
Through the support of the US National Fish and Wildlife Foundation, The Reef-World Foundation is now working with the Philippine Department of Environment and Natural Resources (DENR) on a project in the Philippines, which aims to focus Green Fins expansion to reefs that have been identified as climate refugia (Figure 1). Cutting-edge research  has recently determined that these coral reefs will not start experiencing severe annual coral bleaching events until years, or even several decades, after others. To predict the time when corals are most likely to be affected by severe annual bleaching events, scientists use Degree Heating Weeks. This is a measure of the intensity and duration of a warming sea. Widespread bleaching and coral mortality are expected to occur when the scale reaches eight Degree Heating Weeks. This represents eight weeks of ocean warming that is at least 1 degree Celsius above the seasonal average. The last coral reefs to experience this level of ocean warming have the best chance of persisting in the face of global climate change.
The impacts caused by marine tourism industries are among the most severe for coral reefs in many areas of the Philippines, and these industries are rapidly expanding to include climate refugia sites. By prioritizing Green Fins expansion to marine tourism destinations at these sites, conservation efforts are focused on areas that may still have time to adapt to warming seas. Green Fins has already been proven to enhance the environmental practices of marine tourism operators within the five sites where it is currently implemented in the Philippines (Figure 1, red circles). This project will support The Reef-World Foundation to build the capacity of managers to further promote sustainable reef-dependent businesses at four climate refugia (Figure 1, green circles). This will engage an additional 60 dive and snorkel operations in implementation of best industry practice, demonstrated through improved environmental impact assessment scores. It also is expected that the project outputs will enable managers and policymakers to take informed action toward strengthening marine tourism laws and regulations for the benefit of coral reefs and stakeholders. This public-private partnership approach allows for effective collaboration and promotes open communication between sectors for maximum conservation benefit.
Chloë Harvey is the programmes manager for The Reef-World Foundation and has led the team to support Green Fins efforts globally since 2008. Chloë is a professional diver and marine biologist.
Charlie Wiseman holds an MSc in Tropical Coastal Management and has supported Green Fins coordination at various locations throughout the Philippines and Vietnam since 2015.
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