EOS Special North Sea

RBINS contributed to the ‘Special Noordzee‘ of the popular science monthly ‘EOS Wetenschap’ (only available in Dutch). Together with the Flanders Marine Institute (VLIZ) and the Research Institute for Agriculture, Fisheries and Food (ILVO), we were part of the editorial board, and several RBINS scientists are featured in various articles. The result is available since 23 June 2022.

No less than 130 pages, about the RV Belgica, CSI marine mammals, non-indigenous shellfish, … and much more !

Hurry to the nearest point of sale! Hard copies can be ordered here.

RV Belgica baptised by HRH Princess Elisabeth in Ghent

On Saturday 25 June 2022, the new Belgian oceanographic research vessel RV Belgica was baptised. The official ceremony took place at the Rigakaai (North Sea Port) in the godfather city of Ghent, where the RV Belgica was moored for a few days for this occasion. None other than HRH Princess Elisabeth honoured the ship by accepting to act as godmother. After pronouncing the baptismal formula « I baptise you BELGICA and wish you and your crew a safe journey. » she successfully broke a bottle of champagne on the hull.

©RBINS/Thierry Hubin
©RBINS/Thierry Hubin

The baptism of a ship is a remnant of an ancient tradition. In ancient times, the aim was to obtain the grace of the gods by offering a sacrifice, in which the blood of a sacrificed person was used. Later, wine replaced the sacrificial blood. Among seafarers, the saying spread: ” A ship that has not tasted wine will taste blood “. The idea is that a ship that has not been baptised will encounter difficulties: storms, damage or accidents … Later still, wine was replaced by champagne, the very symbol of celebration, success and happiness! Today, of course, this is regarded as superstition, but a baptism ceremony is still the occasion to bring together all those involved in the building, exploitation and operation of a ship, to officially welcome it and to wish it a successful future. The RV Belgica, which arrived in Belgium on 13 December 2021 and started her scientific activities on 27 January 2022, can now set sail without fear of disaster (wink wink).

©RBINS/Thierry Hubin

Prominent Attendees

The baptism ceremony of the RV Belgica was attended by Mr. Vincent Van Quickenborne, Deputy Prime Minister and Minister of Justice and the North Sea, Mr. Thomas Dermine, State Secretary for Relance, Strategic Investments and Science Policy, Admiral Michel Hofman, Rear Admiral of the King and Chief of Defence, Mrs. Carina Van Cauter, Governor of the Province of East-Flanders, Mr. Mathias De Clercq, Mayor of the city of Ghent, Mr. Arnaud Vajda, Chairman of the Belgian Science Policy Office, Divisional Admiral Jan De Beurme, Wing Adjutant of the King, Commander of the Navy and Deputy Admiral BENELUX, Mrs. Patricia Supply, General Director of the Royal Belgian Institute of Natural Sciences and Mr. Frank Monteny, General Director Research and Space of the Belgian Science Policy Office.

Numerous representatives from the scientific world, the various components of Defence, the local, provincial, regional and federal authorities, and the business community descended on the Rigakaai for the occasion. Mr Marcos Freire, General Director of Freire Shipyard, the Spanish shipyard that built the RV Belgica, Mrs Beatriz Larrotcha Palma, Ambassador of Spain to the Kingdom of Belgium, and Mr Eric Derriën, General Director of the operator Genavir, also attended the baptism ceremony.

Secretary of State Dermine: “The fact that Princess Elisabeth accepted to act as godmother of the RV Belgica is a great honour and a powerful signal that underlines our shared belief in an ambitious future for Belgian science policy. With no less than four times as much laboratory space as the previous Belgica, this 71-meter-long flagship will be able to make a strong contribution to marine research in Belgium and Europe. Ghent is a logical choice as a godfather: in the Artevelde city, the thirst for knowledge and the relationship with water determine the history, the identity and the future of the city.”

©RBINS/Thierry Hubin

Lots of Protocol

After the presentation of the invitees and a word of welcome by Secretary of State Dermine, who presided over the ceremony, the actual baptism was the first ceremonial element of the event, which lasted just under an hour in total. However, those present were then presented with a great deal of additional protocol.

The following attributes were donated to the RV Belgica: the Geus (a square flag with the national tricolour which is waved by way of salute) was presented by Secretary of State Dermine, the flag of auxiliary ship of the Navy by Division Admiral De Beurme, and the ship’s bell (a bronze bell in which the ship’s name is engraved) by Mayor De Clercq.

This was followed, with the consent of HRH Princess Elisabeth, by the recognition of the Commander of the RV Belgica, Corvette Captain Gaëtan Motmans, by Division Admiral De Beurme. He then addressed Mrs Supply for the secondment of the Commander, the Second Officer and the Chief Mate to the Royal Belgian Institute of Natural Sciences.

The certificates about the sponsorship of the RV Belgica were exchanged by Commander Motmans and Mayor De Clercq, whereupon the Mayor addressed the public.

Finally, the Commander and crew of the RV Belgica embarked, and Secretary of State Dermine invited HRH Princess Elisabeth for a visit on board, where she signed the golden book and received some technical and scientific demonstrations.

©RBINS/Thierry Hubin
©Defence/Michel Cauffmann
©Defence/Michel Cauffmann

Additional Activities

Adding to the stay of the RV Belgica in Ghent, some activities accessible to the public were organised. On Friday 24 June, the scientific symposium ‘RV Belgica – A ship for the future’ took place in the Aula of Ghent University, and on Saturday 25 June (morning) and Sunday 26 June (entire day), the public was given the opportunity to visit the ship. A science fair was also held on board, where various scientific users presented and demonstrated their activities. The fact that seats had to be reserved for a visit to the RV Belgica and the science fair was not a superfluous measure: the RV Belgica was continuously filled to capacity.

On the Rigakaai there was also a technology fair where visitors could discover the activities of DEME/NH Marine, Expo Marine, Hulpbetoon van de Marine/Entraide de la Marine, IC Defence, ABC Engines, North Sea Drones, Statamat and Thales. There were also several food trucks and opportunities for a drink, while young and less young children could enjoy themselves on a bouncy castle, climbing wall and death ride.


The baptism ceremony of the RV Belgica and the welcome activities were jointly organised by the Belgian Science Policy Office (BELSPO), the Royal Belgian Institute of Natural Sciences (RBINS), the Belgian Navy, the Cabinet of the Secretary of State in charge of Science Policy, the Military Household of the King, the operator Genavir, North Sea Port, the City of Ghent and the University of Ghent, with the support of the Local Police Ghent, the Maritime Police and the Fire Brigade Zone Centre.

The Belgian Science Policy Office (BELSPO) represents the Belgian State as the owner of the RV Belgica, the Royal Belgian Institute of Natural Sciences (RBINS) manages the calendar, budget and scientific instrumentation, the Belgian Navy provides the bridge personnel and the home port of Zeebruges, and the operator Genavir is responsible for the integrated management and operation of the ship.

Oil spill excercise in offshore wind farms

On Tuesday 28 June 2022, an exercise took place at sea to clean up a simulated oil slick within the offshore wind farms. The purpose of this exercise was to test and optimise procedures, resources and inter-service cooperation in case of an oil spill at sea. The Marine Environment Service of the FPS Public Health coordinated the exercise with all the services involved. Deputy Prime Minister and Minister of the North Sea Vincent Van Quickenborne visited the ships. The Royal Belgian Institute of Natural Sciences contributed by providing aerial and modeling support.

Mechanical recovery using a sweeping arm system on the Zeetijger (DAB Vloot) (© RBINS/MUMM)

Fast response

The number of oil spills in the North Sea requiring clean-up has fallen sharply in recent years, and in 2021 not a single oil spill was detected in the North Sea. Regular aerial surveillance, vessel inspections and the monitoring of satellite images ensure a deterrent effect on illegal discharges. However, an accident is still possible and a quick response with anti-pollution agents is necessary to limit damage to the environment. The increasing transport of oil by water due to the war in Ukraine increases the risk of this type of incident.

Spraying system with dispersants on board the P902 Pollux (Belgian Navy) (© RBINS/MUMM)

On land, at sea and in the air

For this exercise, a large oil slick was simulated with straw, which drifted into the Seastar and Nobelwind wind parks. The coastguard centre notified the Marine Environment Service, which started a clean-up operation. With the assistance of Rescue Zone 1 (Bruges-Ostend region), the material was transported to a vessel of the Navy and a vessel of DAB Fleet. Once installed, the vessels could set sail and start combating the incident on site. In the air, the aircraft of the scientific service Management Unit of the Mathematical Model of the North Sea (MUMM, part of the Royal Belgian Institute of Natural Sciences) kept an overview of the entire combat operation. In the meantime, this service created models to determine the origin of the oil and to predict where the slick was drifting to. These models made it possible to use targeted equipment, should it have been necessary to upscale.

Mechanical recovery using a sweeping arm system on the Zeetijger (DAB Vloot) (© FPS Public Health)

Control techniques

The technique that is initially used in the Belgian part of the North Sea is mechanical recovery. This means that the oil is collected and brought ashore for processing. If this tactic is not possible, a chemical agent can be sprayed on the oil to break it up into smaller droplets. These can be better cleaned up by nature with its self-cleaning ability. Putting a chemical dispersant into nature and leaving the oil in the water is not the first choice but can be used in emergencies, subject to a scientific consideration of pros and cons and approval by MUMM. Both techniques were tested in this exercise.

Spraying system with dispersants on board the P902 Pollux (Belgian Navy) (© RBINS/MUMM)

Smooth cooperation

This type of exercises are possible thanks to a solid cooperation between different partners. Agreements such as the one signed on 13 July 2021 between the Marine Environment Service, Civil Protection and Rescue Zone 1 and good relations between the coast guard partners contribute to the success of exercises and real combat operations.

Vincent Van Quickenborne, Deputy Prime Minister and Minister of the North Sea: “The North Sea is our largest nature reserve. We must protect it well. We do this by fighting air pollution and removing litter from the sea. But an accident happens quickly. Especially in one of the busiest marine areas in the world. Action must be taken quickly. Since last year, the Marine Environment Service, Civil Protection and Rescue Zone 1 (Bruges-Ostend region) have joined forces. This way, any pollution in the event of an incident can be dealt with quickly and efficiently.”

Spraying system with dispersants on board the P902 Pollux (Belgian Navy) (© FPS Public Health)

Participation of the Belgian airborne surveillance in the monitoring of chemicals during French MANIFESTS Sea Trials and monitoring of ship emissions at the ECA border

From 30 May to 2 June, the Belgian aerial surveillance aircraft carried out an international mission to Brittany in France. The aircraft is owned and operated by the Royal Belgian Institute of Natural Sciences (RBINS) and is frequently used in Belgium in the framework of the Coast Guard. International missions are also on the agenda. The purpose of this mission was twofold: the aircraft took part in an international sea trial for the detection and monitoring of chemical pollution and checked with the sniffer sensor the air emissions from ships at the border of the Emission Control Area (ECA) for compliance with the international emission regulations laid down in the so-called MARPOL Annex VI.

Slick of a chemical product behind the SAPEUR, as observed by the Belgian coastguard aircraft.


In contrast to the increasingly less frequent occurrence of oil pollution, pollution by other chemical substances at sea is steadily increasing. As a result of the increasing transport of chemical products by tankers, and the complex international legislation (MARPOL Annex II) allowing the discharge of certain substances under specific conditions, the impact of chemical pollution on the marine environment is also showing an upward trend.

The variety of transported chemicals is large, which creates many challenges for the authorities responsible for monitoring and enforcement. Among other things, the detection and identification of chemicals on the sea surface by airborne units is very complex. In addition, there is still insufficient knowledge about the behaviour of different chemicals at sea, which complicates the modelling of the drift of these pollutants in time and space.

The project MANIFESTS (MANaging risks and Impacts From Evaporating and gaseous Substances To population Safety) tries to meet these challenges. For this project, the main categories of transported chemicals were identified. Different sensors were tested for their ability to identify different substances.  This was first done in a laboratory environment, but the ultimate test was a sea trial where sensors were tested on ships and on flying units. The focus here was on highly evaporating substances.

From the ship ‘SAPEUR’, various chemicals (in limited quantities) were discharged in a controlled manner over two days at the test site near Brest.

During the exercise at sea, different substances were discharged into the sea (in limited quantities), after which they were observed by different flying units. The Belgian coastguard aircraft was one of four aircraft used in the exercise, alongside the Spanish and French coastguard aircraft and a research aircraft of the French Office National d’Etudes et de Recherches Aérospatiales (ONERA). The coastguard aircraft were mainly used for slick mapping (for the purpose of modelling), and for detection by radar and infrared. The ONERA aircraft was equipped with 2 hyperspectral sensors specially developed for the detection of chemicals both on the water surface and in the atmosphere (gas clouds).

The exercise at sea went well and the Belgian coastguard aircraft was able to make a constructive contribution to the collection of field data. It is now up to the scientists to fine-tune the models and to optimize the sensors so that chemical discharges can be better monitored in the future.

Slick of a chemical product behind the SAPEUR, as observed by the Belgian coastguard aircraft.

The RBINS (Marine Forecasting Centre/MFC) is involved as partner in the MANIFESTS project. It is mainly responsible for the further development of mathematical models that can simulate the drift, behaviour and fate of harmful substances other than oil (so-called HNS – Hazardous and Noxious Substances). The aim is to reduce the knowledge gaps of in-house models by implementing the newly acquired knowledge on evaporation, fire and explosion processes of gases and evaporators, and by carrying out a thorough inter-comparison and validation exercise of models to better understand their strengths and weaknesses. The RBINS also contributes, among others, to the development of a decision-support system (DSS; proof of concept) that will integrate useful information such as model simulations, an HNS database, vulnerability maps, etc. with the aim to facilitate the crisis management of HNS incidents by competent maritime services.

Infrared camera picture of a chemical slick.

Monitoring of ship emissions at the ECA border

The MANIFESTS Sea Trials took place just west of Brest, in French waters. Since this is also the zone where the ECA border is located, where ships have to switch to low-sulphur fuels when entering the area, it was decided to combine the participation of the Belgian Coast Guard aircraft in the MANIFESTS exercise with a check for violations of the international regulations on ship emissions. A total of 62 ships were checked during the mission. 18 of these were in the immediate vicinity of the ECA border, the other vessels were observed on the way to and from Brittany. Of the 18 vessels at the border, six showed suspicious sulphur levels, while two had high NOx emissions. One vessel was found with both high NOx emissions and high sulphur content in its fuel. Not all of these observations concern violations as some vessels were observed just outside the ECA, although most likely their emissions were already above the limit during the last part of their passage in the ECA.  A more detailed analysis has yet to be carried out, but these preliminary results clearly indicate that increased monitoring at the ECA border could be very useful for improving MARPOL Annex VI enforcement. Belgium has been a leading international player in this area for years and is trying to create support for this with other North Sea coastal states, within the framework of the Bonn Agreement. One of the Belgian proposals is to jointly organize intensive control campaigns at the ECA border. This mission can already serve as an interesting case study to demonstrate the importance of such type of campaigns.

Air emissions of a container vessel.

Open Ship Weekend RV BELGICA, 25-26 June 2022, Ghent

On Saturday, June 25 (morning) and Sunday, June 26 (full day), the public will have the opportunity to visit the new Belgian oceanographic research vessel RV Belgica in her godfather city, Ghent. For this occasion, the RV Belgica will travel to the Rigakaai (North Sea Port, Ghent) where she will be officially christened in the afternoon of Saturday, June 25.

For a visit to the RV Belgica, a registration is required (see further). On board, one can discover life on board a research vessel and attend demonstrations by various scientific users of the vessel (science fair).

The event area – with the exception of the RV Belgica – is freely accessible to the general public during the open door moments, without registration. In a technology fair, you can discover the activities of DEME, NH Marine, Expo Marine, Hulpbetoon in de Marine/Entraide de la Marine, Information Centre Defence, ABC Engines, North Sea Drones, Statamat and Thales without having to register. On the quay you will also find food trucks and opportunities for a drink, as well as some additional activities.

The christening ceremony on Saturday afternoon is a closed event for which the public cannot register.

Practical information


On Saturday 25 June, visitors can board the RV Belgica from 9h30 to 11h30. By 12h30, the last visitors should have left the ship. The event site closes at 14h.

On Sunday 26 June, boarding is possible from 9h30 to 11h30 and from 13h30 to 17h30. Visitors have to disembark at 12h30 pm and 18h30 pm respectively. The event site closes at 18h30.


You can reserve your places for a visit to the RV Belgica here.

Additional Information

As parts of the RV Belgica offer limited mobility, carrying backpacks etc. is discouraged. Prams, buggies, wheelchairs etc. are unfortunately not allowed on board due to the access via a gangway and the many stairs that have to be climbed in the ship. Please bear the many stairs in mind if you are planning to visit the ship with small children.

Use of public transport is encouraged. For those who come by car, there are parking facilities in the area between the Sint-Theresiastraat and the Dukkeldamstraat (Stukwerkers wasteland, NW of the event site on the other side of the Grootdok where the RV Belgica will be moored), on the grounds ‘Park & Ride Stad Gent’ (SE of the event site along the Vliegtuiglaan) and on the grounds ‘Park & Ride Muide’ (SW of the event site, S of the roundabout).

Follow RV BELGICA online !

Facebook: https://www.facebook.com/HowBigIsBelgica.be/

Twitter: https://twitter.com/HowBigIsBelgica

Website @ RBINS: https://odnature.naturalsciences.be/belgica/en/

Website @ BELSPO: https://www.belspo.be/belspo/NewRV/index_en.stm


The ‘Open Ship Weekend’ of the RV Belgica is an organisation of the Belgian Science Policy Office (BELSPO), the Royal Belgian Institute of Natural Sciences (RBINS), the operator Genavir, the Belgian Navy, North Sea Port, the City of Ghent and the University of Ghent, with the support of the Local Police Ghent, the Maritime Police and the Fire Brigade Zone Centre.

Symposium ‘RV BELGICA – A ship for the future’, 24 June 2022, Ghent

On Friday 24 June 2022, the symposium ‘RV Belgica – A ship for the future‘ will take place in the Aula of Ghent University (Campus Aula, Voldersstraat 9, 9000 Ghent; 14h-18h30).

Registration is open to all interested parties until Monday, June 20th, at 17h (as long as there are seats). You can register via this link.

The symposium will be held in English.

Directions: EnglishDutch


  • 13h00 – 14h00 Registration
  • 14h00 – 14h15 Welcome – Prof. dr. Mieke Van Herreweghe, Vice-Rector of Ghent University
  • 14h15 – 15h30: Session 1
    • 14u15 – 14u30 Prof. dr. Ann Vanreusel (UGent) “Future opportunities and challenges for marine life science research”
    • 14h30 – 14h45 Prof. dr. David Van Rooij (UGent) “To boldly go where no one has gone before: geoscientific challenges for RV Belgica
    • 14h45 – 15h00 Dr. Patrick Roose (RBINS) “Science-based Marine Management: Practice and Future
    • 15h00 – 15h15: CPV Guy Schotte (RMA) “RV Belgica: A burden or an added value for Belgian Defence?
  • 15h15 – 15h45 Coffee break
  • 15h45 – 16h40 Session 2
    • 15h45 – 16h00 Dr. Lieven Naudts (RBINS) “RV Belgica: A ship for the future
    • 16h00 – 16h15 Dhr. Tom Nees (DEME) “Importance of RV Belgica for the Belgian offshore industry
    • 16h15 – 16h30 Panel discussion
  • 16h30 – 16h40 Closing – Patricia Supply (General Director RBINS), representing Thomas Dermine, State Secretary for Science Policy, Recovery Program and Strategic Investments
  • 16h40 – 18h30: Reception
Image: Freire Shipyard



Public consultation: Applications for an environmental permit for sand- and gravel extraction

Nieuwpoortse Handelsmaatschappij nv and DEME Building Materials NV have applied on March 29th, 2022, for the prolongation and extension of their concession for sand and gravel extraction in the Belgian part of the North Sea. These applications are subject to an environmental impact assessment procedure.

© RBINS/K. Moreau

The applications and the environmental impact assessment report, including a design of appropriate assessment, can be downloaded below (in Dutch).


Environmental impact assessment report

Results of the consultations (added when available)

The public consultation runs from 31 May 2022 until 30 June 2022.

Any interested party can submit its views, comments and objections to Ms. Brigitte Lauwaert by letter or email until 15 July 2022.

MUMM Attn. Ms. Brigitte Lauwaert
Vautierstraat 29
1000 Brussels


Combining oyster and sugar kelp farming with oyster reef restoration in Belgian offshore wind farms : promising results of the UNITED project

Multi-use of marine space is an instrument for the optimal use of scarce space without exceeding the carrying capacity of the ecosystem. In the relatively small Belgian part of the North Sea, research into such possibilities for multi-use of marine space is becoming increasingly necessary.

UNITED, an international research and innovation project co-financed through the European Union’s Horizon 2020 programme (running from 2020 to 2023), does just that. UNITED stands for Multi-Use offshore platforms demoNstrators for boostIng cost-effecTive and Eco-friendly proDuction in sustainable marine activities, and aims to demonstrate the viability of multi-use of marine space through the development of five demonstration pilots in the European marine environment.

Figure 1: Example of an oyster restoration structure, filled with scour protection material, shell material and adult European flat oysters Ostrea edulis (©Annelies Declercq, Ghent University-ARC).

Within UNITED, the Belgian pilot project, coordinated by Ghent University, and partnered by Jan De Nul Group, Brevisco, Colruyt Group, Parkwind and the Royal Belgian Institute of Natural Sciences (RBINS), combines aquaculture and ecological restoration of European flat oyster (Ostrea edulis) reefs with cultivation of sugar kelp (Saccharina latissima) in an offshore wind farm. Before going offshore, several materials and methods are evaluated in a nearshore test site at the Westdiep area (5 km off the coast of Nieuwpoort, Belgium). The most promising techniques are further optimised nearshore and subsequently applied offshore.

Figure 2 : Scientific diving inside the Belwind offshore wind farm. Divers disembark the new RV Belgica with a RHIB to sample oyster restoration structures in order to evaluate flat oyster settlement success and reef formation on the different materials (©Thomas Kerkhove, RBINS).

Ideal monitoring conditions

Spring 2022 kicked off with some bright and sunny days. This allowed the project partners to monitor the 2nd generation of seaweed nets at the nearshore test site (a first generation of nets was tested in 2020-2021) and also provided them the opportunity to organise the first offshore scientific diving campaign to inspect the oyster restoration structures. The structures used are gabions, filled with scour protection material, shell material and partly also with living adult flat oysters (Figure 1), and aim to identify best suitable substrates and conditions for flat oyster settlement and reef restoration. The restoration structures are installed on the scour protection of several monopiles within the Belwind offshore wind farm.

Figure 3 : Yellow lift bag near a Belwind monopile. Scientific divers connect such lift bags to oyster restoration structures that were installed on the scour protection of the monopile, after which they are inflated to rise up and transport the samples to the surface (©Annelies Declercq, Ghent University-ARC).

Under the scientific diving lead of Alain Norro (RBINS), and through the coordination by Parkwind, the oyster restoration structures were successfully sampled and brought on board for further inspection (Figures 2 and 3). Sampling was partly conducted from the new research vessel RV Belgica, with spacious laboratories that allowed for immediate processing of part of the samples.

Figure 4 : Scour protection material with settlement of juvenile European flat oyster Ostrea edulis (circle) (©Francis Kerckhof, RBINS).

Promising results

The RBINS and Ghent University (Artemia Reference Center, ARC) teams discovered successful settlement of juvenile flat oysters on the added materials (Figure 4), in numbers that have never before been observed in the Belgian offshore wind farm zone. An additional interesting observation was the presence of tube-building polychaete worms (Sabellaria spinulosa, figure 5), which are, under certain conditions, capable of forming reefs, as was also apparent here. Although these are only small-scale results, they are promising for future restoration efforts of biogenic reefs in the Belgian part of the North Sea.

Figure 5 : One of the oyster restoration structures filled with scour protection material. The scour protection stone on the right clearly shows the tubes of the polychaete worm Sabellaria spinulosa, which forms embryonic reef (indicated by arrows) (©Annelies Declercq, Ghent University-ARC).

At the same time, the Ghent University (Phycology) and Brevisco teams sailed with the “Stream” to the Westdiep test site to check up on the seaweed cultivation trials. One of the aims of these trials is to determine the best feasible way to cultivate sugar kelp in the Belgian part of the North Sea. Following the first successful seaweed harvest in May 2021, the researchers are now fine-tuning the best practices to optimise sugar kelp growth for the upcoming cultivation trials in the offshore wind farm in the next growing season (2022-2023). To do so, juvenile sugar kelp was seeded on different substrates using several techniques. These seeded substrates were installed at Westdiep in November 2021. Over winter, the small juvenile sugar kelps of around 1 cm in length have grown substantially. They now cover a considerable surface of the substrates (Figure 6), setting the scene for another promising harvest in May 2022.

Figure 6 : Healthy looking sugar kelp Saccharina latissima during the spring inspection in April 2022 at the nearshore test site (Westdiep, 5 km off the coast of Nieuwpoort) (©Jessica Knoop, Ghent University-Phycology).


Text by Thomas Kerkhove (RBINS), Jessica Knoop (Ghent University-Phycology) & Annelies M Declercq (Ghent University-ARC).

What lies beneath the busiest shipping lane of the world? Discovery of a biodiversity hotspot in Belgium’s farthest offshore waters

Scientists of the Royal Belgian Institute of Natural Sciences discovered a hotspot for underwater life in the Belgian part of the North Sea. In the farthest offshore Belgian waters, beneath one of the busiest shipping lanes of the world, full-fledged colonies of long-living fauna, linked to a seafloor composed of considerable amounts of rocks and stones, were found. Ecologically important species have been observed, including numerous colonies of the soft coral ‘dead man’s fingers’. The gravel bed also housed the first living specimen of the European flat oyster on the Belgian seabed in decades. In Belgium, this species has recently only been found on artificial structures such as wind turbines and quay walls.

Example of a relatively dense gravel bed displaying stones colonised by tubeworms and mature colonies of the soft coral dead man’s fingers (Alcyonium digitatum). Image acquired using an underwater video frame. ©RBINS

The Belgian part of the North Sea represents a small portion of the Greater North Sea, covering only about 0.6 % of its surface area. Despite its size, the diversity and extent of human commercial activities, ranging from intense routed navigation, commercial fisheries, to infrastructural development for the production of renewable energy, and the extraction of marine sands, result in amongst the most intricate marine spatial plans of Europe. Belgian waters are known as a predominantly sandy seafloor environment, renowned for the widespread presence of large sandbanks, historically known as a major hazard to navigation.

It’s not just Sand in the Belgian North Sea

Nonetheless, the existence of natural hard substrates, generally referred to as gravel beds and composed of lag deposits (leftover coarse sediments from which the finer material was washed out by wind, currents, tides), pebble, cobble, and boulder stones, has been known for long, and is relatively well documented both historically and recently. Regional sediment distribution maps show that approximately 15% of the Belgian seafloor consists of potential gravel beds, the majority of which are to date, geologically and biologically unexplored. Globally, the ecological relevance of this substrate type is an undisputed fact as, under the right conditions, stones can become home to a diverse fauna and flora, creating biological reefs, and representing ecologically unique areas within the otherwise vast and predominantly sandy and muddy seafloor.

The earliest available documentation linking the Belgian ‘stony’ grounds with a highly distinctive fauna originates from the 20th century explorations (1898 – 1939) of Professor Gustave Gilson, a Belgian pioneer oceanographer and former director of the Royal Belgian Institute of Natural Sciences (RBINS). However, our gravel areas have greatly diminished due to intensive and pervasive fishing activities, ploughing the sediment, and overturning the stones, and in places, even removing them from their natural location by direct harvesting along with the fish catch, resulting in loss of this unique habitat. After all, stones from the North Sea can be very decorative (a.o., because of the calcareous overgrowth of tube worms, making these stones, to some, an embellishment of the garden) and removing them from a fishing ground eliminates the risk of damage to the nets when they are recaptured. The resulting process of habitat degradation is such that the gravel bed habitat, and several of its typical species, have been brought to the brink of local extinction. A characteristic example of species loss from these offshore grounds, mainly due to overexploitation, is that of the once proliferating European flat oyster (Ostrea edulis), a species of high ecological importance, but also of great commercial interest.

Stones and typical associated underwater fauna, sampled with a Gilson dredge. ©RBINS

Favourable Ecological Conditions

Despite the overall degraded state of the Hinder Banks gravel beds, recent research by scientists of the Royal Belgian Institute of Natural Sciences has documented the existence of various small refuge areas with fragile and resilient typical fauna. Therefore, a large area of the Hinder Banks gravel beds was designated as a ‘Special Area of Conservation’ (Vlaamse Banken) in 2012 and became part of the Belgian Natura 2000 network.

Over the past four years, extended research on the distribution of the gravel bed areas in the farthest offshore Belgian waters beyond the Hinder Banks region led to the discovery of a natural gravel bed habitat in seemingly favourable ecological conditions, right beneath the main shipping lane. Using state-of-the-art oceanographic instruments on board the former Research Vessel A962 Belgica, 5 km2 of this “underwater biodiversity hotspot” was mapped and observed with unprecedented detail.

The Belgian part of the North Sea, indicating zones with gravel bed potential (green), the study area (yellow) and the discovered gravel beds in good ecological condition (red). ©RBINS

The seemingly favourable ecological conditions are inferred from the widespread presence of typical gravel bed species colonising the stones, including numerous colonies of the soft coral dead man’s fingers (Alcyonium digitatum; approximately 200 colonies / 80 m2). Additionally, it was the first time in decades that a live specimen of the European flat oyster was recorded from the Belgian seafloor. This species has recently only been found in Belgium on artificial structures such as wind turbines and quay walls.

Other ecologically important species include a range of bivalve and gastropod shells, crustaceans, fish, sea chervil (Alcyonidium diaphanum), hornwrack (Flustra foliacea) and sea beards (Nemertesia antennina).

Such an area is highly ecologically relevant: hard-substrate habitats provide unique ecosystem services. The structural complexity of stony seafloors provides microhabitat for a range of animals which live either attached on the stones or amongst the created cracks and crevices. Organisms that live attached to the stones can have quite complex morphology, often resembling plant structures, which can serve as a secondary substrate for other organisms to attach. Such biogenic substrates can be soft or hard and are created by various animals, from reef and tube-building worms to erect and arborescent hydrozoans and bryozoans. This increased structural complexity not only promotes the occupancy by a diverse fauna, but also acts as ideal spawning and nursery ground, shelter and/or feeding areas for several other species in their various life stages. Since many of these animals feed by filtering the water mass, they contribute to waste remediation and water clarity. Indeed, where foundation species such as kelp forests, seagrasses and macroalgae canopies are scarce, as for the predominantly sedimentary seafloor of the Southern North Sea, the ecological importance of hard substrate-habitats increases substantially.

Living individual of the European flat oyster (Ostrea edulis) attached to a stone. The specimen was captured during the first visit to the newly discovered gravel bed area in 2018. The stone also houses the tube-building worm Spirobranchus triqueter, the soft coral Alcyonium digitatum, as well as small colonies of polyps and bryozoans. ©RBINS

Sheltered by a Shipping Lane

Given the turmoil of human activities, of which commercial fishing in particular, the discovery was surprising. Indeed, inspection of regional commercial fishing intensity maps in this study area, accounting for the activity of Belgian, French, Danish, German, Dutch, and British fleets, showed that a fishing hotspot exists here, as the area is fished more than five days every year. However, a more detailed investigation of the local fishing patterns revealed that activities are mostly limited to the use of passive and mid-water gears, with only a minor use of bottom destructing gears. This suggests that the busy shipping lane perhaps acts as a prevention against bottom disturbing fishing activities, allowing for the typical fauna to develop. The discovery was made in one of three search zones for seabed protection that have been laid down in the Marine Spatial Plan 2020-2026 of the FPS Health, Food Chain Safety and Environment. In these search zones, it is possible to install protection zones for bottom integrity, which is currently being worked on. The aim is to protect valuable natural elements by only allowing fishing techniques that do not disturb the seabed.

The scientific findings on the detailed mapping of the natural gravel bed and ecological analysis are summarised in a 2021 paper published in the Journal of Remote Sensing. In this study, underwater acoustics and videography were combined to map the habitat’s distribution and to study the effect of stone size with respect to their colonisation by the typical fauna.

“We are currently continuing to monitor this new area and the Hinder Banks region, now using the new RV Belgica Giacomo Montereale Gavazzi, first author of the publication, says, “but the discovery already suggests that biological communities that are associated with gravel beds can persist and recover in Belgian waters”. In the framework of future marine spatial planning and nature conservation and restoration, “this area may serve as an example for this habitat elsewhere in Belgian waters and generally, in the wider Southern North Sea region”. Moreover, “The fact that such animals exist in this area raises the expectation that shipping lanes throughout the North Sea could represent corridors of natural hard substrate biodiversity hotspots”.

Vincent Van Quickenborne, Deputy Prime Minister and Minister of the North Sea: “For the first time in decades, a living specimen of the European flat oyster has been found on the Belgian seabed. This find is all the more special because it was made in a gravel bed in ecologically good condition under one of the busiest shipping lanes in the world. This is a zone where anchoring is prohibited but fishing is allowed. This does not happen very often as there is a mandatory sailing direction here, so fishermen cannot sail back and forth here. The discovery of the gravel bed was done in one of the three search zones for bottom protection that have been laid down in the Marine Spatial Plan 2020-2026. We are now going to give this gravel bed extra protection. As Blue Leader, we not only have to protect the ocean far away, but also the special nature in our own North Sea.”

Example of a dense gravel bed with stones colonised by tubeworms. Several common starfish (Asterias rubens), common whelks (Buccinum undatum) and a soldier (Chelidonichthys cuculus) can also be seen. Image obtained using an underwater video frame. The green laser pointers are 10 cm apart. ©RBINS

The RBINS seafloor mapping efforts are realised by the research groups MARECO (Marine Ecology and Management) and SUMO (Suspended Sediment and Seabed Monitoring), in the framework of research on gravel bed ecology, seafloor integrity and national environmental monitoring studying the effects of human activities. Bathymetric data from Flemish Hydrography, as well as fisheries data from the Flanders Research Institute for Agriculture, Fisheries and Food, further provided the necessary context to the study.

King Philippe visits research vessel Belgica

On Thursday 21 April 2022, His Majesty King Philippe visited the new research vessel RV Belgica. On this occasion, the Belgian Head of State and Commander-in-Chief of the Belgian Army (the naval component provides the bridge personnel and the homeport of Zeebrugge) was received and accompanied by Mr. Thomas Dermine, Secretary of State in charge of Science Policy, Mr. Arnaud Vajda, President of the Board of Directors of the Belgian Science Policy Office (BELSPO), Mrs. Patricia Supply, General Director a.i. of the Royal Belgian Institute of Natural Sciences (RBINS), Mr. Léandre Brehier, Administrative and Financial Director of Genavir, and of course by RV Belgica Captain Gaëtan Motmans and RBINS coordinator of the RV Belgica Mr. Lieven Naudts.

©Belgian Navy/Jorn Urbain

During a short trip at sea, the importance and functioning of the RV Belgica were extensively explained. This attracted great interest from King Philippe, which translated into many questions to those involved.

The programme started with an expert explanation of the ship and its scientific programme by Captain Gaëtan Motmans and Belgica coordinator Lieven Naudts. Their words formed the perfect stepping stone to some demonstrations of the various scientific activities that Belgian and international scientists can carry out thanks to the RV Belgica, and which put our country at the forefront of marine scientific research internationally. Attention was paid to biological, chemical, physical, geological and hydrodynamic research, and the demonstrations included both sampling (water and seabed samples) and laboratory activities (with thanks to the crew of the RV Belgica, and to Laura Lemey and Coenraad Deputter – ILVO, David Van Rooij – Ugent, and Kyra Gesquiere and Tom Scholdis – KBIN). Subsequently, King Philippe took the time for more extensive converstion with Belgica regulars. In addition to the persons mentioned above, 2nd Commander Anthony Willaert, Chief Engineer Antoine Samzun and Chief Electrician Andrejs Jankins of the RV Belgica were given the honour to talk with the King, as well as Mr Patrick Roose, Operational Director Natural Environment of the RBINS, Mrs Alice Matossian (Ugent), Mr Kris Hostens (ILVO) and Mr Michael Fettweis (RBINS).

On the occasion of his visit, King Philippe also signed the Golden Book of the new RV Belgica.

After the event, the RV Belgica got ready for her first international campaign, the same afternoon she set sail for the Mediterranean Sea.

©Belgian Navy/Jorn Urbain
©Belgian Navy/Jorn Urbain
©Belgian Navy/Jorn Urbain
©Belgian Navy/Jorn Urbain
©Belgian Navy/Jorn Urbain
©RBINS/Kelle Moreau
©RBINS/Kelle Moreau
©RBINS/Kelle Moreau
©RBINS/Kelle Moreau
©Belgian Navy/Jorn Urbain
©Belgian Navy/Jorn Urbain