Living Loggerhead turtle on Bredene beach

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.

© Walter Rogiers

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.

© Institute of Natural Sciences/Francis Kerckhof

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.


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.

Public consultation ‘Princess Elisabeth zone’

The Federal Public Service Economy, SMEs, Self-Employed and Energy has submitted an application for an authorization for the construction and a permit for the operation of offshore windfarms and parc cabling in the Belgian part of the North Sea. This application is subject to an environmental impact assessment procedure.

The application, the environmental impact statement and the non-technical summary can be consulted from 24 November to 25 December 2023 at the offices of MUMM (Management Unit of the Mathematical Model of the North Sea) in Brussels (Institute of Natural Sciences, Vautierstraat 29, 1000 Brussels;; tel 02 627 43 52) or Ostend (3de en 23ste Linieregimentsplein, 8400 Ostend;; tel. 02 788 77 22), by appointment only and during office hours between 9:00 am and 5:00 pm. The application can also be consulted at every coastal community, during office hours. The list of locations and contact persons of coastal communities is available by simple request to MUMM.

The documents can also be consulted electronically:

Any interested party may submit its views, comments and objections to Ms Brigitte Lauwaert by letter or email until 8 January 2024:

Institute of Natural Sciences/MUMM

Attn. Ms. Brigitte Lauwaert

Vautierstraat 29

1000 Brussels

Successful first EcoMPV Sampling Campaign: Insights into Early Colonization on Littoral Modules

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.

One of the littoral modules, prior to the sampling event. (© Institute of Natural Sciences/MARECO)

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.

Overview of the different components available within the Artificial Hard Substrate Garden. (© Hendrik Gheerardyn)

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 (


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

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

Orca stranding on the Belgian coast

On October 29, a male orca was spotted off the coast of Coxyde, the first confirmed case of this species in Belgium in the 21st century. A few hours later, the severely weakened animal washed up in De Panne, where it died almost immediately. The autopsy took place on the beach on October 30. To what extent the weakening and death of the orca should be associated with old age or health problems remained unclear. The origin of the animal is also not yet known.

Image: Institute of Natural Sciences/Jan Haelters

In the morning of Sunday, October 29, a large but unidentified sea animal was spotted on the border of Nieuwpoort and Oostduinkerke. A little later, Laurent Raty noticed the large sword-shaped dorsal fin of a marine mammal off the coast of Coxyde. It was immediately clear that it could only fit a male orca (also called killer whale). The animal moved slowly southwest along the coast and news spread quickly.

Image: Filip De Ruwe

When, an hour later, it appeared that the orca had meanwhile barely moved on to off Saint-Idesbald, and was lingering there, hundreds of spectators rushed to the shore hoping to catch a glimpse of the animal. This did not prove difficult, as the flat sea made the orca visible from afar. However, the animal also sometimes approached to within just a few dozen metres of the tide line.

Image: Vincent Legrand

Inevitable stranding

Lots of ‘oohs and ahhs’, but the apearance of this orca in the southern North Sea, its slow swimming and dangerously close approach to the shoreline were bad signs. The euphoria quickly turned when it became clear that the animal would wash up with the rising tide. An ultimate attempt by the lifeboat Brandaris (Ship Support, Nieuwpoort) to encourage the orca to choose open sea had no effect.

Image: Institute of Natural Sciences/Kelle Moreau

At a quarter past two in the afternoon, the orca washed ashore in De Panne, just across the border with Saint-Idesbald. Once the tide had gone out, the very skinny animal died almost immediately. Apart from its weakened condition, the loss of the supporting power of the water also plays a role. On dry land, the pressure of its own weight on organs, blood circulation and respiration quickly becomes too great.

Image: Institute of Natural Sciences/Kelle Moreau


Because of the size of the animal – 6.13 m long – and the desire to keep the body as intact as possible for the autopsy, and also to preserve the skeleton, it was decided to organise the investigation into the medical background and cause of death of the orca on site.

The autopsy was performed on Monday morning, 30 October, by staff from the faculties of veterinary medicine at Ghent University and Université de Liège and the Institute of Natural Sciences. The general public could follow the event, which took about three hours, from a distance. All body parts and organs were inspected externally and internally, and various tissue samples were collected for further microbiological (diseases) and ecotoxicological (chemical contamination) studies.

Image: Institute of Natural Sciences/Kelle Moreau

Cause of death?

Analysis of the digestive system showed that the stomach and intestines were completely empty, meaning that the animal had not managed to obtain food for some time. The thin layer of subcutaneous fat and severely worn teeth also seem to be related to this. These findings are consistent with the externally observed emaciation and weakening of the animal.

Inspection of the other organs revealed signs of infection of the lymphatic system, and minor bleedings in the intestinal wall. The severity and role of these in the weakening and death of the orca are being further investigated microbiologically. The other organs showed no visible signs of infection or obvious pathology. No suspicious amount of internal or external parasites was found either.

The extent to which the orca’s weakening and eventual stranding and death should be linked to advanced age (and natural death), underlying health problems, or a combination of both, is thus not yet fully established.

Image: Institute of Natural Sciences/Kelle Moreau

Orcas in Belgium

There are hardly any well-documented cases of orcas in Belgium from past centuries. Four reports are known from the 20th century, and for an older stranding we need to move back in time to 1850. More recent cases (including some reported in 2022) could not be sufficiently documented to be retained as certain. The animal of 29 October 2023 thus concerns the first confirmed orca in Belgium in the 21st century. In the meantime, it became known that he was also filmed at sea on Thursday, October 26, along the northern French coast between Wimereux and Boulogne-sur-Mer.

Although an orca also washed ashore in Cadzand (The Netherlands) in October 2022, an orca was found in the French river Seine in May of the same year (neither of which survived), and other rare and unexpected marine mammals turned up in the southern North Sea in recent years, we should be cautious in interpreting these figures because of the low numbers. The same goes for pointing out causes for the appearance of these species in areas where they do not normally occur.


The origin of the Belgian orca also remains unknown for now. The orca is a cosmopolitan species, meaning it can be found all over the world, but usually lives in populations that are more or less resident within well-defined areas (which can be quite large). The southern North Sea has no local population; the closest orcas live in Scotland, Norway and the southern part of the Bay of Biscay (N Spain).

Orca populations are invariably well monitored by local scientists, and individuals are usually known and documented in photo databases. Individual recognition is thereby often possible based on markings, fin shape and any damage and scars. The orca from the Belgian coast is currently being compared with photos from these databases. So far, no similarities were found with orcas from the Iberian Peninsula (Spain – Portugal), Madeira, Scotland and Ireland. A possible origin from populations of Norway, Iceland and the Azores is still being investigated further.


Thank you

An explicit word of thanks goes to the local police and fire brigade, the city services of De Panne, the rescue services, the civil protection, the staff of Ghent University and the Université de Liège, the colleagues from the Institute of Natural Sciences and the FPS Public Health, Safety of the Food Chain and Environment, and to the numerous volunteers and other stakeholders who played a role in monitoring and documenting the orca, managing the beaching, the public and the autopsy.

The municipality of De Panne gave the unfortunate orca the name ‘Reveil’, after the initiative that aims to take Flemish mourning culture into the 21st century and of which De Panne may call itself ‘consolation capital’ in 2023. On the eve of the orca’s stranding, 10,000 candles were placed on De Panne’s beach in this context.

Publication Nature Communications Earth and Environment : International maritime regulation decreases sulfur dioxide but increases nitrogen oxide emissions in the North and Baltic Sea

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 26th, 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.

Belgian Coastguard aircraft operated by the Institute of Natural Sciences (© Institute of Natural Sciences/MUMM)

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.

Evolution of potential non-compliance in the European SECA

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 (NOx) 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 NOx regulations, an issue on which the Institute of Natural Sciences and other researchers have published before.

Increase in NOx emissions between the periods 2019-2020 and 2021-2022

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.

International Research Ship Operators meet in Bruges

From 16 to 20 October 2023, the UNESCO world heritage city of Bruges was the scene of the 34th annual meeting of the International Research Ship Operators. The meeting was organised by the Institute of Natural Sciences and the Flanders Marine Institute. 129 participants attended the meeting to share information and solve problems of common interest. Improving support for the marine scientific community’s research efforts at sea is always a key focus.

International Research Ship Operators, 16-20 October 2023, Bruges, Belgium

The International Research Ship Operators (IRSO) forum brings together research ship operators representing 49 organisations from 30 countries. Together, they operate more than 100 of the world’s leading marine science research vessels. Membership of IRSO is open to all organisations operating research ships and national research programmes that collect data from ships at sea and follow established protocols for the open publication of their results.

IRSO was founded in 1986 and since then has had annual meetings organised by and in participating countries. In 2023, the Institute of Natural Sciences, operator of the RV Belgica, and the Flanders Marine Institute, operator of the RV Simon Stevin, took care of the organisation. Together, they also guarantee the Belgian representation in IRSO. 129 participants travelled to Bruges for this 34th IRSO meeting. Besides plenary sessions and some specific workshops, which took place at the Bruges Grand Hotel Casselbergh, the programme also included some social activities. A visit to the research vessels RV Belgica and RV Simon Stevin was, of course, a must. For this occasion, both ships were docked at the Zeebrugge Naval Base on Friday 20 October.

RV Simon Stevin and RV Belgica at the Zeebrugge Naval Base (© Institute of Natural Sciences)

Objectives of the annual meeting

Sharing successful experiences (best practices) in the design and operation of research vessels and scientific equipment are among the main objectives of the annual IRSO meeting.

“These meetings allow efficient sharing of information and resolution of problems of common interest. This allows the marine scientific community’s research efforts at sea to be ever better supported” clarifies Greg Foothead, chairman of IRSO and General Director of New Zealand’s NIWA Vessel Management Ltd.

Giuseppe Magnifico, IRSO vice-president and Deputy Director of the Italian Consiglio Nazionale delle Ricerche (CNR) completes, “IRSO also acts as a voice to promote the research ship community and provides expert advice to other bodies as required.”

Additional benefits

However, IRSO also goes a step further than keeping each other informed about experiences and developments in national research fleets. “Being active within IRSO sometimes also results in actual collaborations and in the exchange of ship time and equipment between institutes and countries,” says André Cattrijsse, Head of Research Infrastructure at the Flanders Marine Institute.

“Moreover, this strategic exchange of knowledge and experience is crucial in an era of declining budgets, while the need for knowledge of coastal seas and the ocean and their relationship with humans is rapidly increasing.” stresses Lieven Naudts, coordinator of the RV Belgica and head of the Ostend Measurement Service at the Institute of Natural Sciences.

From left to right: André Cattrijsse (Flanders Marine Institute), Giuseppe Magnifico (vice-president IRSO), Greg Foothead (president IRSO) and Lieven Naudts (Institute of Natural Sciences) look back on a successful IRSO meeting (© Institute of Natural Sciences)

IRSO also initiates projects of common interest to its members. For example, a code of conduct for marine research vessels was developed and IRSO contributed to the creation of the OCEANIC database for research vessels at the University of Delaware. IRSO also sponsors workshops and working groups, such as the biennial International Marine Technician’s Workshop (INMARTECH).

Sea change: new blueprint for Southern Ocean survival

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.

Southern Ocean sea ice breakout (© AAPP)

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.”

Fin whale sounding at ice edge (© Richard Youd, AAD)

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 (, 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.
Emperor penguins at Auster colony (© Pat James, AAD)


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.

Aerial surveillance on oil and gas platforms during Tour d’Horizon 2023

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.

Oil spill from a drilling rig in Norwegian waters (© RBINS/MUMM)

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.

Three orcas in Norwegian waters (© RBINS/MUMM)

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.

The Belgian TdH2023 team (from left to right: operators Ward Van Roy and Jean-Baptiste Merveille, pilots Dries Noppe and Alexander Vermeire) (© RBINS/MUMM)
The TdH missions take place in a very different environment from the surveillance over the Belgian waters (© RBINS/MUMM)

Knokke Leatherback Turtle died as a result of acute trauma

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.

Leatherback Turtle washed up dead on Knokke beach, 7 October 2023 (© RBINS/J. Haelters)

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.

Leatherback Turtle washed up dead on Knokke beach, 7 October 2023 (© RBINS/J. Haelters)

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.


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.

The Leatherback Turtle on the autopsy table (© RBINS/J. Haelters)
Inside of the oesophagus with remains of Rhizostome (© RBINS/J. Haelters)
Piece of plastic from the digestive system (© RBINS/J. Haelters)
Detail of the head (© RBINS/J. Haelters)

New impulses for interdisciplinary ocean observing and forecasting

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.

Dr Toste Tanhua, chemical oceanographer at GEOMAR Helmholtz Centre for Ocean Research Kiel, led the EuroSea project. (Image: UNESCO/Fabrice Gentile)

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.