Preliminary survey of Boulder Island An Overview of documented Species on and around Boulder Island and proposed future measures of improvement A preliminary survey conducted by the Team of Project Manaia – Association for Ocean Conservation April 2016 Preliminary survey of Boulder Island 1 Table of Contents 1 Table of Contents 2 2 Location 4 3 Current state 6 3.1 Marine survey 6 3.1.1 Objective 6 3.1.2 Observed species 6 3.1.3 State of the Boulder Island Reefs 12 3.1.4 Dynamite fishing around Boulder Island 13 3.2 Terrestrial Surveys 14 3.2.1 Objective 14 3.2.2 Observed species 14 4 Suggested Measures 17 4.1 Water based measures 17 4.1.1 Permanent moorings 17 4.1.2 Reef top protection 18 4.1.3 Coral care 19 4.1.4 Coral garden / reef rejuvenation 19 4.1.5 Proposing a No-take Zone 20 4.1.6 Long term observation 21 4.2 Land based measures 21 4.2.1 Regular Beach cleanups 21 4.2.2 Wind and weather monitoring 22 4.2.3 Fresh water supplies 22 4.2.4 Salt water flushing for toilets 22 4.2.5 Suggestions for other bungalows 22 4.2.6 Gardening 22 4.2.7 Micro grid solar power 22 4.3 Other Suggestions 23 4.3.1 Up cycling trash found on beaches 23 4.3.2 Research collaborations 23 4.3.3 Hiking paths across the island 23 4.3.4 Resting areas/viewpoints 23 4.3.5 Provide guests with garbage bags on arrival 23 4.4 Research Barge 23 4.4.1 Securing option A 24 4.4.2 Securing option B 24 5 Literature 25 6 Table of Figures 26 7 Appendix 27 7.1 Species lists 27 7.1.1 Coral 27 7.1.2 Anemones 27 7.1.3 Fishes 28 7.1.4 Echinodermata 29 7.1.5 Molluscs 29 7.1.6 Others (marine) 29 Project Manaia – Association for Ocean Conservation 2 Preliminary survey of Boulder Island 7.1.7 Plants 30 7.1.8 Birds 30 7.1.9 Mammals 31 7.1.10 Reptiles 31 7.2 List of endangered species in Myanmar 32 Project Manaia – Association for Ocean Conservation 3 Preliminary survey of Boulder Island 2 Location Boulder Island is located within the Mergui Archipelago in southern Myanmar (Fig 1). Fig 2 shows the general overview of Boulder Island with the key bays and various hiking paths. Figure 1 - Overview of Mergui Archipelago & Boulder Island Project Manaia – Association for Ocean Conservation 4 Preliminary survey of Boulder Island Figure 2: Satellite imagery of Boulder Island with key labels. Brown lines indicate hiking trails Project Manaia – Association for Ocean Conservation 5 Preliminary survey of Boulder Island 3 Current state 3.1 Marine survey 3.1.1 Objective To survey the present species around the island and propose a dedicated area for reef rejuvenation in Boulder Bay and suggest immediate steps for better protection of the existing coral. 3.1.2 Observed species Coral A large variety of various coral species (Fig 3-5) were found throughout the sampling area, with two species prominent in the waters around Boulder Island. Heliopora coerulea (Fig 4) appears very prominent in Boulder Bay as well as Sisters Bay. This species is identified by the IUCN as vulnerable at this stage and the abundance of it around Boulder Island helps to make a strong case towards protecting this area. Heliopora coerulea is particularly susceptible to coral bleaching due to its shallow distribution and therefore greater risk of disappearing within one generation and consequently is closely observed in many regions. The second highly abundant species is Montipora tuberculosa (Fig 3), which represented more than 50% of the coral in Moken Bay during the survey period. Though it is listed as Least Concerned from the IUCN, this coral in Moken Bay is well established, but also under the threat of coral bleaching. As its habitat is in shallower water, which is more sensitive to temperature changes, this put additional stress on the coral and the potential of becoming endangered. During the survey we identified several IUCN Red Listed coral species, though without long-term survey and more rigorous observations, the exact species could not be identified. These species and several coral types are in desperate need of protection (Appendix 7.1.1). Even with only a few species identifications and a relatively brief survey, the coral around Boulder Island should be able to make a strong point towards a No Take Zone designation and lay the groundwork towards more detailed research work (genetic IDs, collecting samples, laboratory identification, etc.) in the future. There are more than 400 coral species documented for the Indian Ocean alone, therefore is difficult to create full species identification. For a more complete survey and listing of all coral species in the survey area, a long-term observation with full SCUBA gear would be necessary. This would allow sufficient time for documenting and collecting detailed observations on the coral and the associated species of fish and crustaceans. Figure 3: Montipora tuberculosa coral Project Manaia – Association for Ocean Conservation 6 Preliminary survey of Boulder Island Figure 4: Heliopora coerulea coral Figure 5: Turbinaria patella coral Project Manaia – Association for Ocean Conservation 7 Preliminary survey of Boulder Island Anemones Several large accumulations of anemones were observed throughout the surrounding waters of Boulder Island. The largest was found on the eastern side of the island with several colonies of Heteractis magnifica (Fig 6) located on top of big coral blocks and boulders at 2 to 7 meters depth. Sisters Bay had the second high densities of Heteractis magnifica in place. Entacmaea quadricolor (Fig 7) was only found in Boulder Bay with only single individuals and no larger colonies were observed. However, this particular kind of anemone is home to Amphiprion amphippion, which was present in the observed samples of Entacmaea quadricolor. This would indicate that there are more individuals in the area than we could initially find. Single individuals of all species (Appendix 7.1.2) were observed throughout all the bays of the island. Figure 6: Heteractis magnifica anemone Figure 7: Entacmaea quadricolor anemone Project Manaia – Association for Ocean Conservation 8 Preliminary survey of Boulder Island Even though anemones and the associated anemone fish are a major attraction for snorkeler and divers in tropical waters, none of the observed species are listed in the IUCN or other organizations for endangerment. However, anemones do provide an indication of water quality around the island. Fish With more than 400 different species of reef fish confirmed in the Mergui Archipelago, Boulder Island contains a large variety of reef fishes ranging across families and of all sizes (Fig 8-10). During every data collection, we could add new species to the full listing of observed species (Appendix 7.1.3), thus increasing the overall species list of Boulder Island. To provide a completed listing of all existing fish species would require a longer research period and full SCUBA gear to reach various depths. A large majority of the observed species during our survey was reef-associated, prominently visible in juvenile fish, as they seek shelter in the reef top as well as in broken coral along the seabed. Figure 8: Arothron nigropunctatus - Black Spotted Toadfish Project Manaia – Association for Ocean Conservation 9 Preliminary survey of Boulder Island Figure 9: Amphiprion akallopisos – Western Skunk Anemone Fish Figure 10: Amphiprion ocellaris - False Clown Anemone Fish Project Manaia – Association for Ocean Conservation 10 Preliminary survey of Boulder Island Echinodermata Various types of Echinodermata were observed during the data collection on Boulder Island (Appendix 7.1.4), none of the observed species were in the listing of IUCN. Nevertheless the abundance of sea cucumbers (Fig 11) is an indication of the health of the substrate. Sea cucumbers clear the substrate from all dead particles and excrete clean sand. The amount of sea urchins also provides an indication of a well-balanced ecosystem. The small accumulations of sea urchins were limited to areas of rich algae growth, as no large areas of bare rock could provide the needed habitation. Figure 11: Bohadschia graeffel - Marbled Sea Cucumber Molluscs A prominent representative of marine mollusks is the Giant Clamp (Fig 12), which was documented in various sizes and colors throughout the surrounding waters of the island. Only a few mollusks were observed during the survey (Appendix 7.1.5), but a larger variety seems to be present, as indicated by the manifold shells found across the Boulder Island beaches. Figure 12: Tridacna maxima - Giant Clamp Project Manaia – Association for Ocean Conservation 11 Preliminary survey of Boulder Island 3.1.3 State of the Boulder Island Reefs The structure and health of the coral reefs around Boulder Island indicates past destruction, but is currently in a state of positive rejuvenation (Fig 14). Large areas of coral, especially inside Boulder Bay, may appear “dead”, but are in fact still alive (Fig 13). After a coral bleaching event, the larger coral died off, causing the colorless (white) coral. However, this stable substrate provides algae the basis for development and reintroduction. Over time coral can grow back onto this stable substrate and build secondary reefs (new reefs using the older primary reef as their base structure). Coral is slow growing and will grow back if suitable stable substrate is present (Fig 14). Boulder Island shows a suitable stable substrate that the coral is using to build secondary reefs. Figure 13: Destroyed Reef Figure 14: Juvenile coral regrown on previously bleached coral with algal layer Large areas of the previously bleached coral are also covered in a brown looking layer.