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On Saturday, November 25, 2023, a live Loggerhead turtle washed up on the beach of Bredene. This species has never before been identified with certainty in Belgium. The animal is currently being closely monitored in SEA LIFE Blankenberge.

Strong northwesterly winds are known to cause all kinds of dead and living material from the sea to wash up on our coasts, and the storm of November 24-25, 2023 was no different. Sometimes surprising animals or objects are also found in the wash-up. In the afternoon of November 25, walkers on the beach of Bredene came across nothing less than a live sea turtle.

The young animal, with a carapace length of only 14 cm, was recovered from the beach by the Ostend fire brigade and reported to the experts of the Institute of Natural Sciences, who identified it as a very young Loggerhead turtle (Caretta caretta). The Institute then arranged for the transport of the lost animal to Sea Life Blankenberge.

First time in Belgium?

Although the Loggerhead Turtle is not exclusively confined to warm waters and is one of the most widespread sea turtles, the North Sea falls outside the range of this species. A number of strandings are known from the Netherlands, including from the 21st century, but as far as we know there have been no confirmed sightings from Belgium. Some old cases are questionable or involve sea turtles of unknown identity. Bredene’s turtle could therefore go down as the first confirmed Loggerhead turtle in Belgium.

When Loggerhead turtles hatch from the egg, their carapace is only 4 to 5 cm long. The carapace of adult animals can reach a length of more than one meter. The animals that previously washed up in the Netherlands had widely varying carapace lengths, from about 20 cm to almost a meter. These therefore involved animals of varying ages, but most were immature. Female Loggerhead turtles only reproduce when they reach a carapace length of 70-80 cm, and are then at least almost 20 (to more than 30) years old.

Atlantic origin?

The Loggerhead turtle is found in all oceans except the polar regions. Like all sea turtles, they lay eggs on beaches. The closest laying beaches to us are in the Mediterranean Sea, but that does not mean that the Bredene turtle comes from there. In the Atlantic Ocean, the main breeding areas should be sought in the Cape Verde Islands (East Atlantic) and in the south-east of North America (Florida, Gulf of Mexico; West Atlantic), and an Atlantic origin is certainly possible in the case of the Bredene Loggerhead turtle.

This can be explained as follows. Immature Loggerhead turtles from North America and Cape Verde make a multi-year tour of the Atlantic Ocean before returning to their native areas. During this life stage, strong currents can cause them to drift away, with the youngest – and therefore smallest – specimens being at greatest risk. Western currents in the Atlantic Ocean mainly occur in autumn and winter, so it is no coincidence that sea turtles in the North Sea also appear most often during this period.

The northwesterly storm of November 24-25, 2023 also caused a lot of material to wash ashore that certainly has an Atlantic origin. In addition to driftwood and other objects with Atlantic biological growth (such as many goose barnacles), this also included buoys from the United States and Canada. It is therefore not unlikely that the Loggerhead Turtle came to us from the Atlantic Ocean on November 25 with the same westerly current.

However, it cannot be deduced from this where the Belgian Loggerhead Turtle was born. For another species that previously washed up along North Sea coasts, the Kemp’s Ridley Turtle (with a dead specimen in Belgium, on January 6, 2012 in Nieuwpoort), a transatlantic origin is the only possibility, because this species only reproduces in the Gulf of Mexico.

Rehabilitation

Because sea turtles that wash up alive in our region have ended up in an area that is unfavorable to them, shelter is always being considered. The Bredene Loggerhead Turtle also had damage to the back of the carapace. SEA LIFE Blankenberge is authorized to take sea turtles into care and organized an initial examination by a veterinarian immediately upon the animal’s arrival. The weight was 770 g, some barnacles were professionally removed from the abdominal shield and a course of antibiotics was started. Additional examination will follow on November 26, during which the animal will be internally screened with x-ray.

The Loggerhead Turtle stays in SEA LIFE Blankenberge in a tank of a suitable size for the animal, where the water temperature is systematically raised. It is still too early to determine whether the animal can be released back into the wild, and where or when that could possibly happen.

Scientists of the Institute of Natural Sciences have concluded the first sampling campaign of the littoral modules within the EcoMPV project (Eco-designing Marine Photovoltaic Installations). This sampling event, conducted on October 23, 2023, aims to investigate the habitat provisioning effect of artificial floating structures for marine fouling fauna and fish, one of EcoMPV’s objectives.

For this purpose, three littoral modules were designed and developed by Jan De Nul Group, in collaboration with the Institute of Natural Sciences and EMBRC Belgium (European Marine Biological Resource Centre). These floating modules act as the foundation for various settlement plates, constructed out of materials interesting for marine offshore installations. The littoral modules were deployed in May/June 2023 in the safety zone of Mermaid offshore wind farm by the RV Belgica and the Zeetijger. This test site closely resembles the water mass present in the Princess Elizabeth Zone (PEZ), a newly designated zone for offshore energy production.

During the campaign, the scientific diving team of the Institute of Natural Sciences retrieved the first batch of settlement plates from each littoral module. On board of the RV Belgica, each plate was photographed for quantitative coverage image analysis and subsequently preserved for taxonomic analysis. The data collected from the littoral modules will provide a comprehensive understanding of early colonization processes, offering crucial insights for the development of eco-friendly marine photovoltaic installations. The EcoMPV project is financed by the Energy Transition Fund of the FPS Economy, GD Energy.

After the completion of the EcoMPV project, the littoral modules will be integrated as scientific equipment in the Artificial Hard Substrate Garden. This is an innovative in-situ experimental platform, managed by the Institute of Natural Sciences, that consists of flexible and modular artificial hard substrate devices. It is designed to study the impacts of man-made structures, including mariculture installations, renewable energy devices, antifouling treatments, coastal protection structures, and more, on marine environments. Graphic designer Hendrik Gheerardyn has recently crafted an informative infographic providing an overview of the devices and their respective sampling range.

The Artificial Hard Substrate Garden is offered as an EMBRC research service to both the scientific community and the industry. For further details, please visit the MARECO website or contact Wannes De Clercq (wdeclercq@naturalsciences.be).

This news item was originally published on the EMBRC website on Nov 9^th, 2023.

Text: Wannes De Clercq, MARECO, Institute of Natural Sciences

Collaborating with researchers from Germany, the Netherlands, Sweden, and Denmark, researchers from the Institute of Natural Sciences (Ward Van Roy and colleagues) assessed the effectiveness of ship emission regulations that have been in place in the North and Baltic Seas for more than 15 years. The findings of this study were published today, October 26^th, 2023,  in the leading scientific journal Nature Communications Earth and Environment. The study was based on more than 110,000 remote ship plume measurements and on-board inspections. Remote measurements were conducted using various fixed monitoring stations and aerial measurements using drones, helicopters, and fixed-wing aircraft.

The data revealed a substantial improvement in compliance rates for sulfur emission limits since the initiation of these measurements. This positive trend was observed across the Baltic Sea and the North Sea. Nevertheless, it was observed that the introduction of the global cap limit of 0.5% FSC (fuel sulfur content) led to a slight increase in SO₂ emissions in the SECA (Sulfur Emission Control Area) from 2020 onward, possibly due to the increased use of scrubbers and the fuel price inflations.

In contrast to the successful reduction of SO₂ emissions from ships, the international ship emission regulations appeared to have no impact on the nitrogen oxide (NO_x) emissions from ships. In fact, there was even an increase observed of ships’ NOx emissions. This outcome can be attributed to various regulatory gaps in the NO_x regulations, an issue on which the Institute of Natural Sciences and other researchers have published before.

These research findings are of particular importance to policymakers and other stakeholders responsible for environmental regulation and enforcement, as they offer valuable insights for developing more effective regulations and strategies for the implementation of emission regulations and their enforcement at sea and in ports.

The full study can be consulted here, with a ‘Behind the paper’ blog post being accessible here.

More than 200 scientists from 19 countries have released the first comprehensive assessment of trends in Southern Ocean ecosystems, in a report written specifically for policy makers. The Marine Ecosystem Assessment for the Southern Ocean (MEASO) stresses that climate change is the most significant driver of species and ecosystem change in the Southern Ocean and coastal Antarctica.

The Southern Ocean around Antarctica is home to unique wildlife and therefore of fundamental importance to biodiversity. It is also crucial to human welfare by providing us with food and helping to control our climate. However, as the Southern Ocean is absorbing most of the global temperature rise, the wildlife is feeling the heat. Together with additional pressures from fisheries, tourism and pollution, this environment and its residents now face an uncertain future.

“Long-term maintenance of Southern Ocean ecosystems, particularly polar-adapted Antarctic species and coastal systems, can only be achieved by urgent global action to curb climate change and ocean acidification,” says Dr. Anton Van de Putte (Institute of Natural Sciences and Université libre de Bruxelles, Belgium), who was a member of the steering committee that supervised the Marine Ecosystem Assessment of the Southern Ocean (MEASO).

The five-year MEASO process was modelled on a working group of the Intergovernmental Panel on Climate Change (IPCC). Dr. Van de Putte, who also actively contributed to a Summary for Policymakers adds: “The MEASO report can be considered like an IPCC report for the Southern Ocean, and in a similar way, the science was distilled into an easy-to-read and concise summary to inform politicians and policy makers around the world.”

The authors of the report also stress that the MEASO process should continue in this critical decade for climate action. Future assessments will be strongly facilitated by archiving, curating and openly sharing data and algorithms. “The SCAR Antarctic Biodiversity Portal (www.biodiversity.aq), hosted by the Institute of Natural Sciences will provide important contributions to this. Such open data systems  will allow bringing the best-available science together in a timely fashion and to harmonise the information for policy makers,” Dr Van de Putte said.

Key Findings

The Summary for Policymakers sets out 40 key findings, including:

• Managing for change: Long-term maintenance of Southern Ocean ecosystems, particularly polar-adapted Antarctic species and coastal systems, can only be achieved by urgent global action to curb climate change and ocean acidification.

• Measuring change: There is a need for investment in sustained and ocean-wide scientific assessment and monitoring of the health of the ocean by the international community.
• Projecting change: Models are needed to understand what future habitat changes and human impacts will mean to different ecosystems, communities and species.
• Value and importance of Southern Ocean ecosystems: The Southern Ocean is globally connected and important to climate and oceanography and provides food and breeding grounds to many migratory species. However, the movement and activities of humans, including the introduction of non-native species, diseases, and pollution, threatens this unique ecosystem.
• Changing habitats in the Southern Ocean: Southern Ocean habitats, from the ice at the surface to the bottom of the deep sea, are changing. The warming of the ocean, decline in sea ice, melting of glaciers, collapse of ice shelves, changes in acidity, and direct human impacts such as fishing, are all impacting different parts of the ocean and their inhabitants.
• Biological changes and vulnerabilities: The organisms that live in the Southern Ocean, from microscopic plants to whales, are facing a changing environment. How most species will react is uncertain, but important foundation species such as Antarctic krill are likely to decline and impact the whole ecosystem.

About MEASO

The Marine Ecosystem Assessment for the Southern Ocean (MEASO) is the first circumpolar interdisciplinary assessment of status and trends in Southern Ocean ecosystems and drivers of change, for use by policymakers, scientists and the wider public. The report was launched on Wednesday 18 October 2023 in Hobart, Tasmania, during the annual meeting of the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR), the international body under the Antarctic Treaty System responsible for the conservation of marine ecosystems in the Southern Ocean, with membership of 26 nations, including Belgium, and the European Union.

Beginning in 2018, MEASO is an open and participatory process involving 203 scientists from across the Antarctic and Southern Ocean scientific community (19 countries), contributing to 24 research articles published in a special research topic in Frontiers journals.

MEASO is a core activity of Integrating Climate and Ecosystem Dynamics in the Southern Ocean (ICED), which is a regional program of Integrated Marine Biosphere Research (IMBeR, which in turn is a joint program of the Scientific Committee on Oceanic Research [SCOR] and Future Earth). MEASO is co-sponsored by the Scientific Committee on Antarctic Research (SCAR) and is also supported by the Southern Ocean Observing System (SOOS), a joint program of SCAR and SCOR.

The MEASO Summary for Policymakers is available to download here.

In early July 2023, the Coast Guard aircraft of the Royal Belgian Institute of Natural Sciences (RBINS) carried out its annual Tour d’Horizon (TdH) mission. This involves checking for oil slicks coming from offshore oil and gas platforms in the Northern North Sea (i.e. outside Belgian waters). The mission yielded detections of no fewer than 30 oil slicks, the highest number ever found by a TdH partner in a single mission.

The TdH mission is carried out every year under the Bonn Agreement and aims to control marine pollution from drilling rigs in the central and northern parts of the North Sea. The focus is on Dutch, Danish, British and Norwegian offshore waters, and Belgium also commits to this operation. The activities of surveillance aircraft from the various North Sea countries are coordinated internationally to ensure optimal surveillance coverage of offshore oil and gas infrastructure.

Highest Number of Oil Spills Ever Detected

During this TdH mission, the Belgian Coast Guard aircraft detected no less than 30 oil slicks. This is the highest number of oil slicks detected by a single aircraft in a single mission since the start of the programme in 1991. Of these detections, six involved large oil spills with a minimum estimated quantity of more than 1 m³. The largest was estimated to be at least 16.9 m³. All but two detections were oil slicks linked to a drilling rig. 17 oil slicks were detected in UK waters, 12 in Norwegian waters and one in Dutch waters.

All detections were reported to the competent national authorities in accordance with the procedures established within the Bonn Agreement.

Aerial Surveillance Complements Satellite Surveillance

It was notable that the satellite surveillance programme (CleanSeaNet) of the European Maritime Safety Agency (EMSA) reported no detections for their satellite passages in the same zone and time period. This shows the primary importance of traditional aerial surveillance with satellite surveillance in support.

Observations of Marine Mammals

Besides oil slicks, the Belgian Coast Guard aircraft was also able to observe orcas and other marine mammals during the 2023 TdH mission. For the first time during a TdH mission, the team was able to photograph two groups of orcas between Norway and Scotland. It is likely that the two groups were part of one single pod of about 10 individuals.

Thanks to the long-standing experience of the crew, functionality and deployability of RBINS’s Coast Guard aircraft, Belgium continues to honour its commitments under the Bonn Agreement. As a result, the RBINS continues to prove its commitment to better protection of the North Sea. However, the aircraft dates from 1976 and is starting to show more technical defects. The replacement of the aircraft is therefore a top priority so that aerial surveillance can continue in the future.

Until a dead Leatherback Turtle was found on the beach in Knokke on 7 October 2023, we knew of only three strandings of this species in our country. The autopsy, which took place on 9 October, shows that the unfortunate animal was in healthy condition when an acute but unknown trauma caused a sudden death.

On Saturday morning 7 October 2023, walkers found nothing less than a washed-up dead Leatherback Turtle (Dermochelys coriacea) on the beach in front of the Zwin Nature Park in Knokke, near the Dutch border. An exclusively marine species that only comes ashore to lay eggs, the Leatherback Turtle is also the largest turtle species in the world (with a maximum length of 2.5 m). The unfortunate animal from Knokke measured as much as 1.73 m and was already in a state of decomposition. Death may have occurred a few days before it was washed ashore.

The Royal Belgian Institute of Natural Sciences (RBINS), which is responsible for organising the research on protected marine species, collected the animal from the Knokke fire brigade after it was removed from the beach in collaboration with the municipality’s technical service.

In the North Sea?

The Leatherback Turtle is a so-called cosmopolitan, meaning the species is found worldwide. It is best known as a species of warm seas, but it is only for egg-laying that beaches along tropical and subtropical seas are important. Outside the laying season, Leatherback Turtles are also found much further north (as far north as Alaska and Norway) and south (as far south as South Africa and New Zealand). In the shallow North Sea, they are very sporadic, but they can feed there during periods with very abundant jellyfish.

Jellyfish are therefore a possible explanation for the appearance of this Leatherback Turtle in the southern North Sea. In the past few weeks, Barrell Jellyfish (Rhizostoma pulmo) in particular have been abundant in our waters, a jellyfish species that is on the menu of the Leatherback Turtle and which peaks in our waters from August to October. It is not inconceivable that the Leatherback Turtle of Knokke followed this food source into the North Sea.

Four strandings in Belgium

In our regions, the Leatherback Turtle is a great rarity. Jan Haelters (RBINS), coordinator of the stranding network and marine mammal expert, gives an overview: “Only three previous strandings of the Leatherback Turtle are known in Belgium. Earlier strandings date from 1988, 1998 and 2000. Furthermore, only a few sightings of live Leatherback Turtles in Belgian waters are known: one in 2018, two in 2019 and one in 2020. The latter was found between Ostend and Middelkerke in the nets of shrimp fishermen, and was able to be returned to the sea alive.”

It seems that the number of cases in our waters is increasing, but with such a small number, it is dangerous to draw such a conclusion. After all, the number of potential observers and the flow of data have also greatly increased thanks to the high digital connectivity in our current world. Nor can a link to global warming be made with such a low number of observations.

Autopsy

The autopsy of the Leatherback Turtle took place on Monday morning 9 October at the Faculty of Veterinary Medicine of Ghent University, in a collaboration between the universities of Ghent and Liège. This revealed that it was a 247 kg female. The remains of Barrell Jellyfish in the oesophagus showed that the animal was eating when it died. A small piece of plastic was found in the gut, but the amount was too small to cause problems. It is well known that animals that eat jellyfish sometimes mistake plastic floating in the water for jellyfish.

Everything seems to indicate that the Leatherback Turtle was healthy when she died suddenly. Although the animal showed no external signs of acute trauma, internally numerous hemorrhages were observed. This indicates a sudden death due to a traumatic event, but it remains unclear what the exact cause of this trauma was.

Within the framework of the EU project EuroSea, 53 partners from 14 European countries as well as Brazil and Canada worked together to improve the European system for ocean observing and forecasting in a global context. In doing so, they provided an important basis for meeting the growing demand for information supporting social and political processes and decisions. About 200 stakeholders met in Paris for the plenary meeting (19-20 Sep ’23) and the final symposium (21 Sep ’23). GEOMAR Helmholtz Centre for Ocean Research Kiel led the project, which is funded by the European Union with 12.6 million euros from 2019 to 2023.

The ocean forms the basis of all life on our planet. It regulates the climate and provides food and oxygen. However, human-induced changes such as pollution, overfishing, warming and other factors are upsetting marine ecosystems. Understanding ocean and coastal processes is essential to maintaining ocean health and sustainable ocean management.

The EuroSea project, funded by the European Union with 12.6 million euros, has filled important knowledge gaps in these areas over the past four years and paved the way for an interdisciplinary and sustainable ocean observation and forecasting system. To this end, the most important European players in ocean observation and forecasting worked together with the users of oceanographic products and services. At the end of September ‘23, the stakeholders met for the General Assembly and a subsequent symposium at the headquarters of the Intergovernmental Oceanographic Commission (IOC) of the United Nations Educational, Scientific and Cultural Organization (UNESCO) in Paris.

Under the leadership of Dr Toste Tanhua, chemical oceanographer at GEOMAR Helmholtz Centre for Ocean Research Kiel and coordinator of EuroSea, the project brought together 53 partners from 14 European countries as well as Brazil and Canada. Participants included scientific institutions as well as private sector partners and international organisations and networks such as IOC-UNESCO, the European Marine Board and the European part of the Global Ocean Observing System (EuroGOOS).

The project partners have set the course for connecting existing ocean observation systems of individual European actors and making ocean data more accurate and accessible to all. For instance, actors of the Blue Economy – an environmentally sound economy based on the use of the oceans, including fisheries, ports, tourism and offshore energy production – and policy makers should be able to make better informed decisions based on the data. At the EuroSea General Assembly, the working groups of the ten individual, interlinked work packages shared their results.

The project has produced numerous innovations that improve ocean observing and forecasting at the European level, in a global context. Among other things, the partners developed a tool to be used by cities and their ports based on data from three test sites in Spain, Italy and Colombia, which provides real-time information and forecasts on waves, sea level, sea surface temperature, thus increasing safety in maritime operations. A system for aquaculture monitoring that uses sensors, unique buoys and advanced modelling capabilities to measure parameters such as oxygen, temperature and pH has also been created within the EuroSea project. It enables targeted predictions of extreme marine events such as marine heat waves and provides aquaculture operators with an early warning mechanism.

At the subsequent final symposium, national and international stakeholders from politics, science and industry were able to inform themselves about the current state of innovations in the field of European ocean observation and forecasting. In addition to addressing upcoming challenges, the discussion focused on recommendations for an effective, sustainable and interdisciplinary system.

In his closing statement, Dr Toste Tanhua highlighted the pioneering nature of the project and advocated for a continuation of the joint efforts at European level: “EuroSea has paved the way towards an interdisciplinary, sustainable ocean observing and forecasting system. We, the ocean experts and stakeholders, are committed to a concerted action to sustainably strengthen the European Ocean Observing and Forecasting System to meet the growing needs of European society and policy and to support the European Green Deal and the Ocean and Waters mission.”

The stakeholders want to build on the collaborations and relationships that have been established through the project. Parallel workshops of the Global Ocean Observing System (GOOS) and a meeting of the European national focal points for GOOS also took place in Paris. There, possibilities for follow-up projects were discussed and experiences exchanged. “We were able to pass on the knowledge we gained directly at the global level”, said Dr Toste Tanhua, who is also co-chair of GOOS.

Project funding:

The EuroSea project is a European Union innovation action funded with €12.6 million from 2019 to 2023 by the European Commission’s Horizon 2020 research and innovation funding programme as part of a call to support the G7 Future of Seas and Oceans initiative.