ISTS42 Program/Agenda

Green (Chelonia mydas) and hawksbill turtles (Eretmochelys imbricata) are frequently observed foraging and resting in the shallow, coastal bays, lagoons, and reefs of the Egyptian Red Sea coast. These areas also attract a substantial number of divers and snorkelers due to their accessibility from the shoreline and the calm, shallow waters they offer, therefore increasing the risk for marine turtles to be injured by boat strikes but also offering opportunities to collect information on these understudied species. Created in 2011, TurtleWatch Egypt 2.0 is a citizen science-based project that aims at collecting information on marine turtles in the Egyptian Red Sea to better understand their abundance, distribution and ultimately their health status. Here we focused on reports of injured turtles obtained throughout the years to better understand injury patterns and estimate recovery rates without treatment, due to the lack of rehabilitation facilities in the area.
Over a twelve-year period (2011-2023), 717 unique turtles were registered, and 8480 sightings were reported. 39 turtles with injuries, sickness, or malformations were observed. Notably, 30 of those turtles were sighted multiple times, enabling in-depth case studies. One of these turtles was reported dead after injury while 26 other turtles exhibited remarkable resilience in recovering from severe injuries.
In 41% of all injured cases, the cause of injury was attributed to boat collision, in 10% of cases we suspected predator attacks, in 28% of the cases we were not able to identify a unique cause of injury. The remaining 21% of injuries were attributed to a variety of factors, for example, genetic pathologies (8%), diseases (5%), cleaning activities (5%) and fisheries (3%). During the study period, we received reports from 212 sites, however injured turtles were registered only in 13 spots, with repeated reports predominantly from 4 sites: Marsa Abu Dabbab, Makadi Bay, Na’ama Bay and Hermes. At these sites, injured turtles represented 16%, 14%, 67% and 16% respectively of the total individual turtles reported for each location.
In Na'ama Bay it was observed that citizen scientists tended to send more frequently information on injured turtles only, regular sightings of healthy marine turtles are likely under-reported from this location. This emphasizes the need for combining citizen science data with future, more scientific research conducted by the team.
These findings stress the significance of directing conservation efforts toward sites with higher injury rates, as they are likely focal points for potential threats to the turtle population. This data yields invaluable insights for resource allocation and conservation planning in the region, particularly where more than three injured individuals were documented.
In conclusion, this study sheds light on the health and conservation status of marine turtles in the Red Sea coastal region of Egypt. By emphasizing the human impact and identifying high-risk areas, it provides a foundation for targeted conservation efforts to safeguard these remarkable creatures and their habitats.

The United States Atlantic Outer Continental Shelf is expected to undergo rapid development with the planned construction of offshore wind farms. Offshore wind data collection, construction, and operation is expected to alter the underwater soundscape due to geophysical seismic surveys, construction activities, vessel operations, and turbine generated infrasounds. The purpose of this study was to determine how leatherback sea turtles may respond to impulsive, low-frequency survey equipment associated with offshore wind leasing activities by the Department of the Interior’s, Bureau of Ocean Energy Management. Leatherback turtles annually migrate and forage throughout the Northwest Atlantic shelf region, and regularly inhabit the waters of Southern New England, USA during the late-summer and early-autumn months. As a result, leatherback behavior could be affected by the construction of wind turbines planned for this region. To study the acoustic effects of impulsive sound on their nearshore swimming and foraging behavior, we equipped thirteen leatherback turtles, during the autumn of 2023, with short-term camera and telemetry tags and towed a seismic sparker behind a vessel to simulate a geophysical survey within Massachusetts state waters. Immediately post-tagging, turtles were left to acclimate for approximately one hour and then were exposed for 30 - 45 minutes to the active seismic sparker emitting a broad-frequency, high-intensity, impulsive sound at one second intervals. In addition to collecting video footage, GPS location, and dive behavior data, we also logged acoustic recordings throughout the deployment from each tagged turtle. Data collected were used to assess the received sound levels for each leatherback and categorize breathing events, foraging frequency, dive patterns, pitch, roll, and location prior to, during, and after the exposure. Preliminary results suggest no interruption to active foraging and turtles were present at the exposure site in subsequent days.

Marine plastic debris has emerged as a pervasive environmental issue affecting the world’s oceans. Plastic pollution has become a serious concern due to its potential to adversely affect wildlife and aquatic ecosystems. Ingestion of marine debris is one of the primary threats to a variety of organisms. Numerous studies have provided evidence of plastic consumption by marine organisms, yet underlying reasons remain undiscovered. Sea turtles, in particular, are known to ingest a substantial amount of marine debris. The prevalent explanation is that sea turtles mistakenly ingest marine litter due to its visual resemblance to their natural prey. Additionally, the study of plastic ingestion driven by chemo-sensory mechanisms is a relatively recent area of research. If sea turtles indeed confuse plastic for prey and ingest it, it is essential to study the specific traits of marine plastic that drive sea turtles to consume it, and the mechanisms by which they mistakenly identify plastic as prey require further exploration. In this study, we aimed to assess the impact of visual and olfactory cues on prey recognition and plastic ingestion by sea turtles. Firstly, we investigated the response of sea turtles to odor solutions made from food, clean plastic, and bio-fouled plastic as compared to their reaction to odor solutions derived from pure seawater. The results indicated an increased biting frequency of the food and bio-fouled plastic odor sources as opposed to seawater odors, but these behavioral responses were not observed in the clean plastic. Secondly, we examined the use of sensory cues in sea turtles to evaluate the importance of visual and olfactory cues for prey recognition. To do this, we used four treatments: 1) visual-only (a horse mackerel decoy), 2) olfactory-only (horse mackerel pieces in a blue jar), 3) visual and olfactory combined (a horse mackerel decoy with horse mackerel odor), and 4) a control (a blue jar). The response of sea turtles was greatest for the olfactory-visual combined cue followed by the visual-only cue and olfactory-only cue. There was a complete absence of response to the controls. Overall, our findings imply a comparable attraction of food and bio-fouled plastic via olfactory sensory mechanisms, potentially explaining the frequent interactions of sea turtles with marine plastic debris. Our study suggested that sea turtles predominantly rely on visual cue for prey detection. Feeding cannot be triggered by olfactory cue alone, but these cues have a stimulating effect, enhancing motivation to forage.

The largest maritime accident to ever occur in Sri Lankan coastal waters happened on May 20, 2021, involving the cargo ship MV X-Press Pearl.The local population, the economy, and the fragile coastal ecosystems have all been profoundly impacted. Even while the environmental impacts appear severe, and review of the various studies shows that the long-term consequences are derived especially due to the huge amount of Nurdles, which are small, pre-production plastic pellets released from the wrecked ship.

Most of the research has been focused only on the environmental, economic, and social impacts related with the shipwreck, but when it comes to biological issues, no in-depth study has been conducted to find the negative impacts of nurdles pollution on sea turtle nesting areas along Sri Lanka's coastline.Thus, the main goals of this study are to evaluate the pollution levels along the Western and Southern coastlines where the Nurdles (which are small, pre-production plastic pellets) pollution occurred and to determine the impact of the shipwreck of the X-Press Pearl on turtle nesting. In addition, strategies for restoring the ecosystems have been proposed along with an identification of the risks facing the turtles. Secondary sources were also given priority for gathering data. The research findings revealed that the western coastal belt was impacted to a greater extent than the southern coastal belt by the catastrophe. There has been one documented turtle death in the Southern coast since then, and 176 turtle deaths that washed ashore in the Western coastal belt by July 7, 2021, have been reported. Another striking finding was that 50% of the coastline belt of Western Province was affected by the Nurdles related environmental impacts and oil pollution. However, seasonal observations showed that the sea turtle nesting in the Southern coast was not greatly impacted. Additionally, investigation reports indicated that chemical and oil spills had caused significant impacts or influence on sea turtle nests in the Western coast. Specifically, the death rate of turtles along the Western coast has increased due to hazardous chemicals such as Nitric acid, Nurdles and oil as per the data gathered from government institutes, official interviews, and field observations. Furthermore, information obtained from those government research institutions and universities revealed that the ship accident may have triggered long-term negative impacts on the coastal ecosystems and the coastal community. As a result, this research has recommended appropriate solutions to protect the marine environment. These include, aware the public on the severity of the ocean pollution, implementing ecosystem restoration, and conducting ongoing education and awareness-raising campaigns. Similarly, conserving turtles ought to be given top priority, and ongoing beach cleanup campaigns to be implemented continuously.

Boa Vista is the easternmost island of the Cabo Verde archipelago, located approx. 600 km off the coast of Senegal, West Africa. In 1979, it was identified as an important nesting site for loggerhead turtles. By 2012, it was estimated that 3,700 females were nesting on Boa Vista alone, solidifying Cape Verde as the third largest nesting site for this species in the world. In 2021, Cabo Verde documented a record number of 156,299 loggerhead turtle nests. Notably, while loggerheads nest on all ten Cabo Verde islands, Boa Vista plays a pivotal role, hosting between 60% to 70% of the total.

However, turtle meat has long been a source of food, income and cultural delicacy in Cabo Verde. As recently as 2007, 1256 nesting female turtles were killed on Boa Vista. This along with increased habitat loss had an unsustainable and devastating impact on the population and led to this sub-population being listed as ‘endangered’ by the International Union for the Conservation of Nature (IUCN).

In response to the dire consequences of uncontrolled poaching, local authorities and non-governmental organizations have tirelessly strived to curb poaching and shift attitudes towards turtle conservation. These collective efforts significantly reduced poaching on Boa Vista, plummeting from 29% of the annual nesting population in 2007 to less than 0.2% in recent years, even as nesting numbers drastically increased.

The threat of poaching now appears to be well under control on Boa Vista through continued and diverse conservation efforts. As a result, we can now focus on the evaluation and addressing of other existing pressures. These include:

Entrapment and “natural” mortality: In 2021 alone, 841 adult female turtles (2.7% of that year’s nesting population) were rescued during nesting activities in Boa Vista Island due to being lost, dehydrated or trapped/entangled with a further 43 recorded as dead. For this reason, our conservation efforts have also been focused on trying to reduce the number of turtles exposed to dehydration, using drones to identify and support lost turtles back into the ocean before the rising heat causes them to perish.

Plastic pollution: A recent study found that plastic pollution on the beaches of Boa Vista has negatively affected turtle nesting behaviour, with increased density of rubbish correlating with a decrease in successful nesting events. Furthermore, an increase in the amount of plastic around turtle nests was negatively correlated with hatching success.

Tourism: The significant development of Boa Vista as a tourist destination has many positive impacts such as employment, but also harmful indirect effects such as unregulated interference by tourists, increased vehicle traffic on nesting beaches, which contributes to further obstacles for the turtles and artificial light pollution, which disorientates both nesting females and hatchlings.

As local NGOs, we are working tirelessly to combat these evolving threats in a variety of ways, combining new technologies and approaches, building relationships, increasing capacities, promoting law enforcement campaigns and contributing to the improved protected area management.

The history of sea turtle egg harvesting in Tambelan Islands (Indonesia) dates back to decades ago when legislation not yet in place. Initially, the utilization was only locally but later becoming a trade commodity and source of subsistence in the late 1980s. Eggs were traded outside the islands even to neighboring countries such as Singapore, Malaysia, and Thailand. Later, sea turtle protection regulations were released in 1990 that prohibited all forms of utilization. However, this does not seem to affect significantly in Tambelan up to now. Rapid surveys were conducted in February and August 2023 to assess current conditions on population density, utilization, and illegal trade of sea turtle eggs, and to explore key stakeholders in the area. During the nesting beach survey, we collected data on sea turtle species, amount of eggs harvested, and its economic value. In addition, identification of local trades and key stakeholders is also carried out. Of a total of 56 islands, there are at least 22 islands where sea turtles frequently nest, of which there are four major nesting sites, i.e., Nangka Island, Genting Island, Uwi Island and Menggirang Besar Island. It is known that green turtles (Chelonia mydas) and hawksbill turtles (Eretmochelys imbricata) nest at Nangka Island, while at Genting Island, mainly hawksbills, while at Uwi Island, is green turtles. During the survey in February, there were 29 clutches containing a total of 3,858 hawksbill eggs and 176 green turtle eggs harvested by the landowner from 3 nights of nesting at Genting Island. While survey in August found 9 green turtle clutches (919 eggs) from two nesting nights at Uwi Island. Record in Genting Island during May – September 2022 showed that there were at least 43,729 (x̅ = 8,656 ± 4,628) eggs harvested. The local price of an egg varies based on season and trade chain ranging from IDR 600 – IDR 3000 (≈ 4 - 20 cents) and might be higher when reached overseas. Thus, the estimated income earned by landowners per month on average can reach IDR 5 million and share 30% for the egg collectorwhich is then cut by 30% for hiring egg collectors. This baseline information along with identified key stakeholders and law enforcement agencies are critical essential for WWF Indonesia in developing sea turtle conservation strategies in this area aimingand simultaneously to reduce egg harvest (poaching threat) by to at least 30%. The fact that the sea turtle egg trade is still a lucrative business and a source of subsistence for locals might render raising awareness challenging unless we offer alternative livelihoods for local communities. Thus, a feasibility study of sea turtle-based tourism will be carried out amongst other conservation strategies that should also integrate with the holistic approach of marine conservation, such as propose the area to be a new MPA for Indonesia, such as strengthening law enforcement and raise awareness. Moreover, collaborative efforts with others, such as WWF Malaysia and WWF Singapore, are also highly useful in combating illegal trade, especially in bordering areas.

Loggerhead turtle conservation, nesting beach monitoring and data collection on Sal Island have been conducted uninterrupted since 2008, covering 16 nesting seasons. This rapidly growing loggerhead nesting aggregation has seen nesting numbers increase from an average of 1,081 nests in the first 5 years of the project to an average of 27,255 nests in the most recent 5 years. Poaching of nesting females, which has been recorded since 2008, has fluctuated with the number of nests laid. This has challenged the conservation effort which has expanded, in response to the increase in nest numbers, to cover 60% more nesting beaches, partly due to increased nesting on smaller, previously underutilised beaches. This increase in nesting has also amplified anthropogenic threats, both from tourism and poaching, and suitable nesting beaches have been compromised, resulting in increased implementation of nest relocations and the use of hatcheries. Hatchery use on the island has expanded from the use of one small hatchery in 2008, to six hatcheries throughout the island, one of which protected on average 1,200 nests in recent seasons (2018-2023). Addressing increasing threats in a growing population has dominated the conservation campaign’s efforts and funding. The successes of turtle conservation on Sal Island will be presented, demonstrating how conservationists are coping with the growing demand for impactful conservation in a rapidly increasing loggerhead population, whilst facing reductions in suitable nesting sites, poaching, and increasing tourism. This will be the first time that this rookery is represented internationally at the ISTS after 16 years of constant conservation efforts.