Turtle Watch Camp
This report aims to give an overview of the work conducted by Turtle Watch Camp, Batu Batu Resort in 2017. This includes the findings and results of the sea turtle nesting season and describes the new marine projects implemented.
Marine Biologist, Turtle Watch Camp, Batu Batu Resort
In 2017, Turtle Watch Camp at Batu Batu Resort received 7588 eggs from 9 islands, resulting in the release of 4543 sea turtle hatchlings. The hatch rate was 60.8% which was an increase of 13.1% and 12.8% from 2016 and 2015 respectively. A total of 5 nests were found poached from Turtle Beach and 5 turtles were washed up dead on our beaches, from boat strikes. Our marine survey showed that Junior Reef is composed of 59% live coral, 10.07% dead coral, with the remaining 39.14% comprised of sponges, gorgonians and substrate. A pilot coral restoration study was started to create a coral nursery at The Pipes and Turtle Bay. Over the course of the year, 238 bags of marine debris were removed during beach and underwater clean-up events with the help of guest and staff volunteers. Our educational activities continued with the development of two new presentations and various interactive activities for guests and staff. After the third year of operation, the Conservation Team continue to find turtle nests lost to poaching and adult turtle fatalities due to boat strikes in the region.
Each sea turtle species plays several important roles in the marine ecosystem - affecting the diversity, habitat and functionality of its environment. They help to maintain the health of the oceans whether by grazing on sea grass, controlling sponge distribution on coral reefs, feasting on jellyfish, transporting nutrients or supporting other marine life with food and habitat (Wilson et al., Oceana).
Four of the seven species of marine turtles occur in Malaysia – Hawksbill, Green, Leatherback and Olive Ridley - but unfortunately, the survival of these animals is threatened. Some species like the Leatherback and Olive Ridley turtles are on the verge of extinction, while other species struggle to survive in the face of continued exploitation and other anthropogenic threats. In Southeast Asia the sea turtles have been used for decades in many different ways, but in Malaysia their utilization is traditionally centred on egg exploitation which is one of the major causes of population decline. Additionally, the commercial hunting and slaughtering of turtles for their meat or other products in neighbouring countries can impact local populations since marine turtles are highly migratory. Fishing industry, marine pollution and the loss of the nesting beaches is also severely impacting the survival of adult populations in the wild (Chan, 2006).
Conservation programmes have been running in Malaysia since the early 1950’s with the first hatchery established in Sarawak. Despite efforts to increase sea turtle populations, they have continued to decline, leading to the almost extinction of two species. According to Chan (2006), the failure lies with the lack of a national policy or strategic plan on marine turtle conservation - their management and conservation falls under the state government, and contrary to Sabah and Sarawak, the legislation in Peninsular Malaysia is inadequate, allowing turtle eggs to be freely traded in the local markets on most states.
More recently, marine turtles have been used to promote tourism in a non-consumptive way, increasing the country’s revenue whilst helping to protect these charismatic creatures. Batu Batu Resort at Pulau Tengah, Johor, was the first tourism company in the State to invest in the conservation of the endangered Green Turtle (Chelonia mydas) and the critically endangered Hawksbill turtle (Eretmochelys imbricata), which come every year to lay their eggs on the island. In 2015, the resort in collaboration with the Marine Park and Fisheries Department officially created the conservation project “Turtle Watch Camp” which has been running for three years. As well as turtle conservation, the project has extended its efforts to monitor and protect the marine habitat, in particular the coral reefs surrounding Pulau Tengah.
In 2017 the project was led by a resident Project Coordinator, Stephen Lee, and a Marine Biologist, Mariana Pereira. During this year TWC aimed to:
- Increase endangered Green and Hawksbill turtle hatchlings’ chances of survival through implementing a controlled hatchery and monitoring in-situ nests.
- Educate tourists, resort staff and local communities on the need for turtle and marine conservation in the area.
- Establish contact with other local conservation projects and standardize protocols and data collection.
- Collaborate with governmental organizations.
- Study and monitor our surrounding coral reefs and marine habitats.
With this report we aim to present the work conducted by the conservation team during 2017. The report is divided into two major parts; Turtle Conservation and Marine Conservation, with a third part dedicated to other projects, finances and recommendations for the future.
TURTLE CONSERVATION PROGRAM
The sea turtle nesting season officially started in January with the first female to lay her eggs on Turtle Beach, and finished in November with the last hatchlings released into the ocean. During 2017, 54 volunteers from different parts of the world joined our conservation efforts bringing manpower, new ideas and revenue to the project. Patrol protocols and the hatchling rehabilitation program were redesigned, new educational talks and presentations were created, collaboration with governmental agencies and conservation projects were strengthened, and egg collector training was conducted by the Department of Fisheries.
Internal Beach Patrols
For the 2017 sea turtle nesting season, the patrol routes and schedules were revised. Volunteers and the conservation team covered Sunrise Beach, Batu Batu Beach, Junior Reef Beach and Long Beach, every two hours, from 08:00/10:00pm to 04:00/6:00am, according to the tide schedules. Once a nesting pattern was detected on the beaches at the back of the island, the volunteers began patrolling from Sunrise Beach until Lagoon Bay. This was to increase the chances of collecting female nesting data and to protect/relocate nests before predation or poaching occurs. During the hatchling season the hatchery was always the first and last place to be checked.
For the first 6 months, a morning patrol was conducted at 7:00 am covering all of the back beaches: Sunset Beach, Angsana Beach, Red Sands, Lagoon Bay and Turtle Beach. However, after discovering several nests poached during the night at Turtle Beach, the beach patrol schedules were revised and the team was split into two groups:
- Group 1 spent the night on Turtle Beach with a camping tent, to ensure more nests would not be poached. The patrol times were determined according to the tide schedules.
- Group 2 covered the hatchery and the other beaches as stated above.
External Beach Patrols
Boat patrols were conducted at 7:00 am around some of the nearby islands: P. Hujong, P. Harimau, P. Mensirip, P. Gual and P. Besar. Once a nest was detected, the patrol was scheduled in accordance to the nesting patterns of the female. Some nests were found poached; others were successfully relocated to the safety of our hatchery. The conservation team should conduct this patrol every day during the next turtle season, since some of the islands presented a high nesting activity.
During sea turtle nesting season, females leave the safety of the sea and come to land in an attempt to lay their eggs. Occasionally females come to land but do not lay eggs, leaving only a track in the sand, called a false crawl. It is a normal behaviour when they cannot find a suitable place to lay their eggs or they are frightened or disturbed. Each species of sea turtle makes a very distinctive type of track in the sand, allowing us to identify whether the track belongs to a Green or a Hawksbill turtle. When a track is identified, the conservation team proceeds with the egg collection and relocation. Whenever a nest is found on Sunrise Beach or Long Beach, above the high tide line, the nest is left in-situ, and protected against natural predators. However for all of the other beaches, the clutches of eggs need to be relocated to the TWC hatchery to avoid poaching by humans. Nests were buried at a standard depth specific for each species: 45cm deep / 20cm wide for Hawksbills (with a width of 25cm at the bottom) and 65cm deep / 30cm wide for Green Turtles (with an enlarged chamber at the bottom).
Turtle Watch Camp works in collaboration with two local egg collectors who collect clutches from islands with difficult access to us and transport them to the safety of our hatchery. For each egg delivered, RM 2.50 was paid to the collector, and for each egg that hatched an extra RM 0.50 was rewarded. Although they play an important role for the preservation of the Johor nesting population, protocols need to be revised in order to increase the clutches hatching success.
After a clutch of eggs is deposited by a female sea turtle we need to wait 50-70 days for the hatchlings to emerge. Biometric data is collected from 10 random hatchlings, and the total number of hatchlings is recorded, before proceeding to the release.
To avoid an excessive waste of energy by the hatchlings while at land, the release occurs in a maximum of 30 minutes after the nest hatches. Occasionally, hatchlings are found to have some deformities on their fins or carapace, especially the ones found alive during a nest excavation.
However, most of them are fit and energetic so they are released together with their siblings. Hatchlings are only kept in rehabilitation if:
- Swimming skills and breathing rhythm are poor.
- Egg yolk was not completely absorbed.
Swimming and breathing tests are conducted, and the egg yolk is monitored until the hatchling is ready to be released. Keeping fit hatchlings in rehabilitation will only decrease their energy and their ability to hunt for food, as well as increase their comfort around humans.
Excavations & Eggs Dissection
An excavation was conducted for every nest three days after the hatch date or, if no hatchlings had emerged, on the 70th day after the clutch was laid. Unhatched eggs were counted, measured and dissected to analyse the stage of development of each egg, and live hatchlings trapped under the sand were released. This method allows us to understand the reason behind an unsuccessful hatch (unfertilized egg, bad handling/transportation procedures, maggot infestation, or natural causes).
The stages of development of each egg were classified as follows:
Stage 1: Unfertilised. No blood vessels, no colour changes. Just Yolk.
Stage 2: Early signs of development. Blood vessels, black pigment, pink colouration. No visible embryo.
Stage 3: Visible embryo. Formed embryo (< 3cm length). Yolk present and larger than embryo.
Stage 4: Formed embryo > 3cm length. Embryo is pigmented. Yolk is smaller than embryo but present.
Stage 5: Formed embryo, pipped shell. No Yolk.
RESULTS & DISCUSSION
During the 2017 sea turtle nesting season, Turtle Watch Camp was able to collect 60 nests with a total of 7588 eggs, from which 4612 hatched, and successfully released 4543 sea turtle hatchlings, achieving a hatching success rate of 60.8%. Hatching success is defined as the percentage of eggs that hatch, which includes the number of dead hatchlings found completely developed outside of the egg shells. 98% of the hatchlings released were Hawksbill turtles (Eretmochelys imbricata) and 2% were Green turtles (Chelonia mydas). A total of 5 nests were found poached: four Green nests at Turtle Beach and one Hawksbill nest at P. Hujong.
In 2017, TWC achieved the highest hatching success since the beginning of the project. There was an increase of 13.1% and 12.8% compared to 2016 and 2015 nesting seasons, respectively. Compared to 2016, this year we recorded an increase of 29.3% of the number of Hawksbill eggs laid and a decrease of 65.7% on the number of Green eggs. These fluctuations on the number of nesting turtles could be related with their natural behaviour since individual sea turtles do not nest every year, with each nesting cycle separated by an interval of two to five years. At TWC, we measure the population status by counting the number of nests produced by the various species every year. However, this figure does not provide an indication of the actual population size since it measures only the mature female turtles that ascend the beaches to lay several clutches of eggs per nesting season. Aside from this, we are not able to capture all Johor’s nesting events in our data.
Nesting Season - Temporal Distribution, Nesting Events and Nesting Attempts
The 2017 sea turtle nesting season started in January with the first clutch of eggs laid at Turtle Beach, and ended in September with a Hawksbill nest from P. Besar. The peak of the season occurred between March and July, when 58 nests (5 of them poached) and 4 false crawls were recorded (Fig. 1). This “bell-shaped” nesting distribution is in accordance with the temporal distribution registered on previous years, with low levels of nesting at the beginning and end of the season and a pronounced increase to peak levels in the middle of the season. Since 2015, TWC was able to safely relocate and/or protect a total of 175 nests, and to record 19 false crawls (Fig. 2).
False crawls occur when females come to land but do not lay eggs, leaving only a track on the sand. This year, from the 4 false crawls (all Green turtles) 2 were found at Turtle Beach, 1 on P. Besar and 1 at Sunrise Beach. There are several reasons to justify these unsuccessful nesting attempts. The one at Sunrise Beach occurred because the female climbed all the way until BB kitchen and was unable to dig through the hard soil. As well as this, sea turtles have poor vision and hearing while on land, but they have a good sense of vibration, which allows them to detect small movements on land. Therefore, when they are frightened or disturbed they can also return to the safety of the ocean without laying eggs.
Hatchery and In-situ nests
From a total of 60 nests, 55 hatched (91.7%) and 5 didn’t hatch (8.3%). The hatchery housed 57 of these nests, from which 52 hatched (94.5%) with a hatching success of 57% (average hatching success=52.7%). The three nests left in-situ at Sunrise Beach achieved a hatching success of 71% (average hatching success=71.7%). Compared to 2016 we recorded an increase of the hatching success by 9% and 24%, for the hatchery and in-situ nests, respectively (Fig. 3).
During early development, the handling and transportation of sea turtle eggs can impact the survival of the embryo. A small rotation of the egg can cause the embryo to dislodge from the inner surface of the egg shell which it is attached to, leading to death. Therefore a difference between the stages of development of each unhatched egg from the hatchery and in-situ nests was expected. Figure 4 shows that 92.9% of unhatched in-situ eggs were in stage 1 of development (unfertilized eggs), a really small amount were found in stages 2, 3 and 4, and none were found in stage 5 of development (fully developed embryo). Since in-situ eggs are not manipulated, natural events and bacteria led to the death of embryos in higher stages of development. When we look at the unhatched eggs from the hatchery, we found higher percentages of eggs in stages 2 and 3, which can be related to the handling and transportation procedures.
The traditional practice of egg poaching around Malaysia has led to a significant decrease in the populations of sea turtles who choose this part of the world to lay their eggs. Leatherback turtles are a sad but good example of how this practice has been affecting their population over the years. Scientists recorded a decline in Leatherback’s nesting trends in Terengganu, from an estimated 10,000 nests annually in 1950s to a mere few in 2000s (Chan and Liew, 1996; Chan, 2006). In order to fight these declines, conservation programmes around the country started to create safe areas where turtle eggs can develop without human and animal disturbances – The Hatchery. Therefore, in Malaysia, hatcheries are the best option to protect endangered turtle eggs and increase the hatchlings chances of survival, since in-situ nests without any protection is not a viable option.
Turtle Watch Camp’s hatchery housed 60 clutches of eggs from 9 different islands off the east coast of Johor in 2017. Pulau Tinggi presented the highest nesting population with 35% of the eggs brought to TWC, followed by Pulau Harimau (18%) and Pulau Mensirip (12%). Pulau Tengah accounted for 9% of the eggs, with a total of 693 eggs from 5 different nests (Fig. 5). Four nests at Turtle Beach were lost due to poaching. In comparison with 2016, there was a decrease in the number of eggs found at P. Tengah and P. Lima, and an increase from P. Harimau, P. Mensirip and P. Hujong.
Transportation of eggs between islands can decrease the hatching success of a clutch due to the boat movement over-water. Over the last three years, TWC has received eggs from
12 different islands (Table 2). However, as demonstrated in figure 6, no significant correlation was found between the distances travelled and the hatching success of clutches from 2015 to 2017 (R2 = 0.0089). For this analysis, in-situ nests were excluded, as well as islands with less than 3 nests – Pasir Landa, P. Sibu, P. Gual – due to a small sample size.
TWC’S egg collectors play an important role in marine turtle conservation, since they randomly patrol the nearby islands in search for new clutches of eggs that are then delivered to TWC, and carefully reburied in the safety of our hatchery. In 2017, Fazali brought to us 29 clutches, increasing his hatching success from 14.3% in 2016 to 49.7% in 2017. Pak Ali achieved a hatching success of 62.1% from a total of 25 clutches, an increase of 5.9% compared to the 2016 nesting season (Fig. 7).
The majority of the unhatched eggs from both Pak Ali and Fazali were in stage 1 of development (73.6% and 61.4%, respectively). Fazali presented a higher percentage of eggs in stage 2 of development (14.5%), however this value decreased 31.8% compared to 2016, suggesting better handling and/or transportation techniques (Fig. 8). On stage 4 and 5 of development we assume that natural causes, bacteria or parasites are the main causes for an unsuccessful hatch, since their development only stopped several days after being reburied.
The reproduction success of the organism is dependent on the percentage of eggs that are fertilized and start developing. However, there are many biotic and abiotic factors that affect hatching success by causing embryo mortality during the incubation on the beach. Even, the percentage of unfertile eggs may negatively affect development of viable eggs within the nest, because they usually decompose and are colonised by microorganisms that may invade the viable eggs and eventually affect their hatching success (Blanck & Sawyer, 1981; Phillott & Parmenter, 2001; Sarmiento-Ramírez et al., 2014). For these reasons, the stage of development of each unhatched egg cannot accurately determine the quality of the egg collectors handling and transportation procedures. Annual trainings should be implemented, to enforce and improve the eggs relocation practices.
MARINE CONSERVATION PROGRAM
Reef Check Surveys
In March 2017, the conservation team was trained and certified as Reef Check Eco-divers by the Reef Check Malaysia program. Reef Check consists of a standard survey method which allows us to observe changes in coral reefs over space and time. Three coral reefs were surveyed around Pulau Tengah – Junior Reef, Sunrise Reef and Northern Reef. One 100 m transect line was deployed, parallel to the shoreline, on each reef. Fish, invertebrates and benthic coverage was recorded, as well as any visible impacts, namely trash, coral damages, bleaching and coral diseases. Annual surveys need to be conducted and the data needs to be submitted to Reef Check Malaysia. Although this is an easy method to evaluate the state of our reefs, the program asks for qualified eco-divers, which is challenging with conservation staff turnover. Nevertheless, Reef Check Malaysia team is available to come and help with the surveys at our island, whenever TWC lacks certified eco-divers.
In order to evaluate the coral coverage and health of P. Tengah reefs, coral surveys were implemented as a new project for TWC. The project aims to identify the main groups of corals and their coverage around the island and, at the same time, evaluate the health of the reefs. The methodology consists of deploying a 25 m transect tape, parallel to the shoreline, in different random points of the reef while scuba diving. GPS was used to mark each transect in order to avoid replication of the same transect. A quadrat, made of PVC pipes, was placed on the left side of the transect tape and a photo was taken (Fig. 9a). The photos were then analysed using the CPCe program (Coral Point Count with Excel extensions). The CPCe is a tool for the determination of coral cover using transect photographs. A code file was created according to the coral features we wanted to analyse, containing 6 major categories (“Coral”, “Gorgonians”, “Sponges”, “Others”, “Dead coral” and “TWS”), 22 sub-categories and 4 notes (Appendix 1). The sub-category “Hard coral (HC)” refers to all unclassified hard corals. The program randomly distributes 30 spatial points on each transect image, and the features underlying the points are user-identified (Fig. 9b). Coverage statistics are then calculated and the results sent to Excel spread sheets automatically (Kohler et al., 2006).
The first coral survey was conducted at Junior Reef with 16 transects of 25 m each, randomly distributed along the coral reef. This accounted for a total of 400 photos, from which 374 were used and 26 were discarded due to the bad visibility present during the field work. Approximately 75% of the reef was covered in less than 3 months of surveys (end July-September), with the help of TWC volunteers.
Junior Reef coral coverage is composed by 50.79% of live corals, 36.61% of sand, rocks, rubble, and others, 10.07% of dead coral, 2.47% of Sponges and 0.07% of Gorgonians (Table 3). Besides the percentage of coral coverage, the survey also allowed us to identify any coral disease and bleaching present on the site: 1.62% of the live corals were found bleaching and no coral diseases were detected. Table corals of the genus Acropora were the most dominant, accounting for 17.60% of all live corals at Junior Reef, followed by Boulder corals (11.42%) and Cabbage corals (7.92%). Soft corals only account for 0.25% of the reef (Fig. 10). From all of the dead corals, 86.5% were classified as dead coral with algae (DCA), 13.4% as dead coral (DC) and 0.1% as recently dead coral (RDC) (Fig. 11).
Coral nurseries can provide young corals for transplantation to rehabilitate areas with reef decline or physical damage. In the month of September, two mid-water coral nurseries (150cm*145cm) were designed and deployed at The Pipes (Long Beach) and Turtle Bay (Turtle Beach) at 3-5 m and 5-10 m depth, respectively.
The GPS coordinates are:
The Pipes: N 02⁰28.557; E 103⁰57.355
Turtle Bay: N 02⁰28.929; E 103⁰57.723
TWC floating nurseries were designed to float in the water column, reducing sedimentation stress on corals. Pieces of broken live Staghorn Acropora fragments were collected from Junior Reef and planted into the nursery. The corals were measured and their growth and health should continue to be monitored every month. The corals should then be transplanted using an epoxy gum, to areas of the reef that are destroyed or to the artificial concrete reef developed by the 2016 conservation team.
STRANDED MARINE ANIMALS
A total of five dead Green turtles washed up on the beaches of Pulau Tengah, from November 2016 to November 2017. After an initial external evaluation we were able to conclude that the cause of death was boat strikes, as all the five turtles presented deep cuts on the carapace, head and/or limbs. Biometric data was collected and external marks recorded (Table 4). No metal tags were found.
Although the cause of deaths was clear, for one of the cases we decided to conduct a necropsy to check if any plastics or oil were found internally. The necropsy conducted on a Green turtle found dead at Concave Wall, on November 17th 2016, at 7:40 am, revealed the presence of oil inside the digestive tract. The signs of a boat strike were clear but we were not able to accurately predict if it was the main cause of death or if the strike only occurred post-mortem.
Marine pollution is one of the major threats for sea turtles. However, Malaysia has a high record of boat strikes on marine turtles. During the nesting season, turtles tend to stay closer to the shore, which makes them more susceptible to be struck by a boat propeller. The nesting season coincides with the higher tourism season, which means more boat movements and more strikes. According to one local fisherman, just in August 2017, 16 Green turtles were killed by boat propellers behind Pulau Besar. A limitation of the boats speed, within 1 mile from the shore, should be implemented and enforced by governmental authorities in order to decrease these events.
Marine Mammals and Sharks
In the month of November 2016, one male Finless Porpoise and one female Black Tip Reef Shark, were found dead at Angsana and Sunset Beach, respectively. The male was severely decomposed and presented a large ventral cut and the lower jaw was missing. The shark female, a baby of 59.2 cm, did not present any external marks and her body was fresh and fit. The causes of death are unknown.
BEACH & UNDERWATER CLEAN-UPS
Throughout 2017, 238 bags of rubbish were collected from Pulau Tengah beaches, with plastics and polystyrene accounting for an estimated 98% of the garbage. Some critical areas were identified (Mangrove island, Rocky point and the rocky area that connects Lagoon Bay to Turtle Beach) according to the accumulation of debris after the monsoon period. Due to the difficult access for guests and children, these areas were cleaned mainly with the help of TWC volunteers.
In June, oil pollutants washed up on our beaches and tar balls were found all the way from Sunrise to Sunset beach. The cleaning process was long and tiring however, after 6 days of intensive cleaning by the conservation and dive team, all the beach areas were oil free. The oil spill spread onto other islands, reaching as far as Tioman Island.
Coincidentally or not, in July 2016 the same occurred at P. Tengah, although on a smaller scale. These events can produce serious impacts on the marine environment.
Underwater clean-ups were also conducted with the help of volunteers and the dive team. Seven fish cages were retrieved from P. Hujong, P. Gual and P. Tengah, and three fishing nets were found trapped around the coral reefs at Sunrise reef, Turtle Bay and Hujong reef.
BATU BATU ISLAND FARM
A small vegetable farm was created by TWC volunteers in front of Long Beach Accommodation. The area filled with jungle vegetation is now cleared, fenced and ready to be farmed. Long beans, pumpkins, tomatoes, peppers, eggplant, chillies and sawi caisim were planted in small containers and placed on a shadow area to protect them from the intense sun radiation, during the first stages of development. Once they were ready, the vegetables were transplanted to the farm.
The Batu Batu Island Farm was designed to be used by any staff interested in planting fruits or vegetables that can then be used in the canteen.
During 2017 two new educational talks were developed by the conservation team: Shark Talk and Marine Mammals talk; and the existing Turtle Talk was updated. The talks aim to educate the guests and volunteers on marine related topics, and increase their awareness on the major problems marine life is facing nowadays.
Families were invited to join our Treasure hunt, during the Earth Day, and create their own Recycled handicrafts for Christmas, made with materials collected from beach clean-ups and resort operations.
Sea Turtle Conservation in Johor – safeguarding their future
Although the conservation projects carried out by TWC this year have been successful, and had a positive impact on the number of juvenile sea turtles released, we believe that the population in the region is in trouble. Nests are still being poached and adults continue to be struck and killed by boats. Without intervention to limit boat speeds and officially protect sea turtles and their eggs, the population is going to continue to decline. Turtles are a flagship species and an icon for ocean health and environmental protection - attracting visitors from foreign countries and inspiring new generations to preserve the environment around them.
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Chan, E. H., Liew, H. C. (1996). Decline of the leatherback population in Terengganu, Malaysia. Chelonian Conserv. Biol. 2 (2), 196–203.
Kohler, K. E. & Gill, S. M. (2006). Coral Point Count with Excel extensions (CPCe): A Visual Basic program for the determination of coral and substrate coverage using random point count methodology. Computers and Geosciences, Vol. 32, No. 9, pp. 1259-1269.
Phillott, A. D. & Parmenter, C. J. (2001). The distribution of failed eggs in sea turtle eggs in green (Chelonia mydas) and loggerhead (Caretta caretta) sea turtle eggs at Heron Island, Australia. Australian Journal of Zoology, 49: 713-718.
Sarmiento-Ramírez, J. M.; Abella-Pérez, E. Phillott, A. D., Sim, J., van West, P., Martín, M. P., Marco, A. & Diéguez-Uribeondo, J. (2014). Global distribution of two fungal pathogens threatening endangered sea turtles. PLOS ONE 9: e85853.
Wilson, E. G., Miller, K. L., Allison, D. & Magliocca, M. Why healthy oceans need sea turtles: the importance of sea turtles to marine ecosystems. Oceana online.
Appendix 1. Categories of the code file used for the coral analysis using the CPCe program.