Sharing 40 years’ experience of working on mangroves – the generous forests of the tidal zone

Sharing 40 years’ experience of working on mangroves – the generous forests of the tidal zone

Discovering mangroves

My enthusiasm for mangrove ecology started in a long house in the Gulf Province in Papua New Guinea. This huge structure was made entirely of mangrove timbers and thatched with fronds of a mangrove palm. Here I listened as my colleague in the Office of Forests negotiated with the traditional land owners for permission to conduct fieldwork. Young men from the village were detailed to observe and assist our team that was to weigh a huge tree within the forest. That sweaty teamwork was my introduction to the idea of biomass – the weight of living matter within a forest. I wondered what the young men would tell the village elders about our activities, but was hooked on mangrove forests after that!

Mangroves are trees that live in tropical tidal waters, where the salt and daily submergence prevents establishment of almost all other trees. Confusingly, but understandably, people also refer to forests of these trees as mangroves. In the last quarter of last century, a large portion of mangrove forest cover was lost due to conversion of these areas for aquaculture of prawns and fish. Encouragingly, in the current century, the value of mangrove forests has come to be more widely appreciated and mangrove loss has slowed with some areas of forest being re-established.

Celebrating the importance of mangroves

Mangrove forests are a vital part of the carbon cycle that buffers us from climate change.  They draw down carbon dioxide from the atmosphere and store the carbon in the leaves, branches and trunks of the trees, but as leaves and woody parts of the trees are shed leaves, carbon is transferred to in the sediment in which they grow and into coastal waters. Remarkably these forests can contain as much carbon in the trees as in rainforests do, but they store much more carbon than rainforest do locked up in the soil in which they grow. Plant waste travelling out on the tides supplies food to coastal waters. The forests also act as nurseries for fish and prawns that are caught in waters offshore. Juvenile fish feed and develop among the protection of roots and move into offshore when able to fend for themselves. Some, such as groupers, move to coral reefs. Mangrove roots stabilise shore sediments and also break up inrushing waves.

The underwater life associated with mangroves – Bonaire Credit : Ewan Trégarot

Mangroves and the work of MaCoBioS

Mangroves range from the northern end of the Red Sea to the North Island of New Zealand and flourish on calm subtropical and tropical shorelines in between. Surf shores are not suitable for mangroves. Though mainly located in the waters of continental Europe, the MaCoBioS project extends into the Caribbean with particular case study sites in Bonaire, Martinique and Barbados, where mangroves play an important role in protecting and feeding juvenile reef fish. In the Caribbean, mangrove forests survive cyclones while protecting the shorelines. Scars of hurricane track are visible in these forests many years after the event. Though much smaller in height and area covered than the huge forests of the Gulf of Papua, these Caribbean forests serve the island communities in numerous ways. They are particularly closely linked with the health of nearby coral reefs, act as key stepping stones for migrating birds, are recreational areas and also destinations for ecotourists. The challenge is to ensure the future supply of these ecosystem services, by taking account of the needs of this generous ecosystem in coastal zone planning.

Strong connection with associated ecosystems such as seagrass beds and coral reefs – Bonaire Credit : Ewan Trégarot

One of the pleasures of working with mangrove ecosystems is that those who do are natural collaborators who are committed to the cause of protecting these ecosystems. I hand over here to Ewan Trégarot to talk about the mangrove component of the MaCoBioS project.

Our experts are studying what are the effects of climate changes and anthropogenic stressors on mangroves and how those multiple pressures interact with each other’s. How can we use remote sensing to monitor the ecological condition of mangroves and the ecosystem services provided? What would happen to mangroves in the Caribbean in 2050 or 2100 given the current climate change predictions? Many questions remained to be answered, and hopefully, interesting elements of response will come up soon. Accordingly, remedial work will be recommended to foster the return of mangroves through replanting, restoring tidal circulation and minimising undesirable threats from urbanisation. There need be no losers if remedies are well planned.  

The generous forest of the tidal zone – Martinique Credit Ewan Trégarot

Text by Prof. Simon Cragg & Ewan Tregarot

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Society & Policy

Developing a deeper understanding of public awareness of climate change, human impacts and the value and management of marine and coastal ecosystems

Marine and coastal ecosystems are important for hundreds of millions of people worldwide, providing food and support livelihoods and ways of life. But they increasingly face a variety of pressures, including climate change, which means we need to make sure we look after them better. Policy makers are increasingly aware

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02/27/2023
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Identifying opportunities for future monitoring, research and management of Bonaire’s National Marine Park

The MaCoBioS team was excited to be in Bonaire last week to run a workshop on “Science-driven management in the Bonaire National Marine Park: Actions, Challenges and Opportunities”. The workshop, held on 26th January 2023, was co-organised with Stichting Nationale Parken Bonaire (STINAPA), the organisation that manages Bonaire’s nature parks

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02/01/2023

Celebrating MaCoBioS’s Women in Science

Celebrating MaCoBioS’s Women in Science

If Science is what you like to do, go for it, society and nature need you!

Within MaCoBioS we are very fortunate to have terrific women scientists contributing to our project. These women are in various stages of their academic career and have been essential to the progress we have achieved within MaCoBioS so far. To celebrate the International Day of Women and Girls in Science this year, we would like to share their thoughts on what they love about being a scientist and their aspirations and messages for women and girls that want to work in Science in the future.

The best part of being a scientist

One of the most exciting parts of doing science is trying to find answers to different questions and working in a collaborative way. It is a questioning process and we share this process with a lot of different people, who nurture it. Interactions between scientists are particularly encouraged in the MaCoBioS project, as it is based on the collaborative work of interdisciplinary teams of 16 different partners.

“Science is about life-long learning and staying relevant, great opportunities for making a real difference, solving challenges, communicating technical science to stakeholders.” Hazel Oxenford​, Professor of Marine Ecology and Fisheries, University of The West Indies.

“I really enjoy contributing with my own perspectives on issues regarding social justice to the MaCoBioS tasks and being able to understand other scientists’ perceptions, ideas and views of the problems coming from their own background. I feel that in science bringing in different perspectives is very enriching and quite fun!” Fabiola Espinoza, PhD Candidate, Lund University.

Scientific work gives us a systematic and practical way to understand the world around us based on observation and fact. It goes hand in hand with logic and reason. This is powerful, because it gives us a framework to address uncertainties, think through problems and make decisions. Through science, we can contribute to solving the most pressing environmental and socio-economic challenges with the final aim of helping society.

Some of our experts in the field (from left to right): Dr Cindy Cornet, Dr Silvia de Juan, Dr Géraldine Pérez

MaCoBioS is a great opportunity and an exciting challenge as it allows us to be part of a brilliant community of scientists that share knowledge and push towards new insights. We contribute to knowledge on marine ecosystem functioning, essential to conservation, and have great networking opportunities. 

The future of women in science

Generally inclusiveness in science for all minorities remains a challenge. In too many research institutions, permanent positions with high responsibilities are still too often offered to men while women are often in precarious positions. Women still hold less than 20% of senior roles in universities and research centers, for example. As MaCoBioS we need to continue pushing for equal opportunities in Science, Technology, Engineering and Mathematics. This still requires huge efforts; a small part of it is recognizing work done by the female and minority groups in the scientific community, promoting and rewarding those achievements.

Some of our experts on the international scene (from left to right): Emily Boyd - Professor at Lund University, Patricia Ricard - President of the the Paul Ricard Oceanographic Institute

Nonetheless, we hope for a bright and promising future ahead with increasing opportunities for women to be heard and make the world a better place for us all. We have advanced a lot in supporting and encouraging participation of women in science over the last years. We are increasingly leaving behind misconceptions that women are unsuited to science or traditional perceptions of scientists being male and dressed in lab coats. But we need to go a step further. In particular, we need to support women to take key roles in decision making in research (funding or leadership). This should be done not only by raising the quota of women participating in research projects, but by spreading awareness on gender equality and encouraging women to innovate and lead. Many new projects such as MaCoBioS present a large number of brilliant women scientists with diverse backgrounds.

Our message to girls that want to become scientists

Science is as diverse as the people who work within it covering topics commonly studied at school such as biology and chemistry through to social and political science and everything in between. Increasingly the lines between these topics are blurred and they integrate all sorts of methods from fieldwork to mathematics and computer science. There are also all kinds of scientists, if you are curious and always looking to learn more you can definitely become one. Continue to be curious, anytime, everywhere, always! Let your eyes and mind always be surprised by new discoveries and experiences. This will allow you to be always eager for new knowledge.

“Science is a beautiful path but one that isn’t easy and you need to be prepared to overcome many obstacles on your way. Sometimes you will succeed but others you won´t. The key is perseverance and resilience.” Dr Gema Casal, Postdoctoral Researcher, Maynooth University

However, becoming a scientist requires a lot of work and a bit of luck. You need to be rigorous, patient and surrounded by the right people who will support you not only in your research work, but also emotionally and financially. Here are a few tips from our experience: 1. Network from the start – opportunities come to those who are known! 2. Think local – Find your local issues, team up with experts around the corner, and take on tractable research questions. 3. Keep up and constantly improve your maths and communication skills – transferable skills are key!

“Becoming a scientist is tough no matter your gender, but still even more so for women, BUT if it is your dream, don’t let gender matters or anything else hold you back and go for it!” Dr. Cindy Cornet, Research Fellow, University of Portsmouth

If science is your passion you need to follow it, no matter if your field is filled with mostly men or older generations. Try to convert these challenges into opportunities, and to be a source of inspiration embracing your femininity, knowledge and skills. Be strong and brave, work in teams, fulfill your ideas and work for achieving your objectives and goals. Believe in yourself, be curious and explore areas that interest you.  Especially, don’t hold back, don’t doubt yourself. Go ahead, we need you!

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Silvia de Juan
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Giogia Verri
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Montserrat Demestre
Catarina Fonseca
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Fabiola Espinoza Cordova
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Mialy Andriamahefazafy
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Emily Boyd
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Cristina Seijo_FGF

Find out more about our team of amazing women by checking out our ‘Meet our Experts’  page.

Text by: Elena Allegri, Mialy Andriamahefazafy, Emily Boyd, Gema Casal, Cindy Cornet, Karima Degia, Fabiola Espinoza, Catarina Fonseca, Elisa Furlan, Silvia de Juan, Alicia N’Guetta, Géraldine Pérez, Bethan O’Leary, Hazel Oxenford, Patricia Ricard, Louisa Wood

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Nature-based Solutions

Research priorities for marine and coastal Nature-based Solutions (NBS)

A core goal of the project MaCoBioS is to develop innovative research pathways and provide evidence-based guidance for marine policy formulation on Nature-Based Solutions (NBS). In delivering this goal, we recently brought together twenty-one researchers from a breadth of scientific disciplines to identify research priorities for advancing understanding and informing

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WORKING TOGETHER TO MOVE FORWARDS WITH NATURE-BASED SOLUTIONS

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10/25/2022
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Celebrating MaCoBioS’s Women in Science

If Science is what you like to do, go for it, society and nature need you! Within MaCoBioS we are very fortunate to have terrific women scientists contributing to our project. These women are in various stages of their academic career and have been essential to the progress we have

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02/10/2022

Mapping Marine Ecosystems

Mapping Marine Ecosystems

Why do we need to map the ocean?

The ocean is essential for all aspects of human well-being and livelihoods. Marine ecosystems provide food, moderate the climate, protect the coast and provide countless opportunities for recreation and cultural experiences. But the living conditions and resources in the enormous water masses of the ocean remain largely unknown and unmapped. 

It is a well-known fact that we know more about the surface of the moon than we do about the seafloor. For example, we know that on average the ocean is 3 km deep, but this doesn’t account for outliers like the Mariana Trench, which stretches to depths of 11 km. So, if we don’t even know the exact volume of the oceans, how can we manage them fairly and sustainably? There are many issues that must be addressed to fully understand and protect the oceans for future generations and maps are fundamental tools to advance research in this regard.

Although the ocean is vast, marine life is not uniformly distributed within it, and some ecosystems are more biologically rich than others. Coastal ecosystems generally contain more oxygen and nutrients and are warmer and sunlit. Thus, they are more diverse than open ocean ecosystems. Understanding and being able to visually represent these differences using mapping techniques is essential to monitor and properly manage marine ecosystems. Without this information we risk depleting vital resources and causing irreversible damage.

How do we map marine ecosystems?

The traditional and most commonly used sources of information to create maps of marine ecosystems are in-situ measurements, taken directly from the area of interest. Depending on the accessibility of the area, the logistical and equipment requirements can range from a pair of boots to SCUBA diving gear and even include oceanographic vessels, if mapping occurs in open ocean.

Another way of obtaining information that allows us to map marine ecosystems are remote sensing techniques, through satellite observations, for example. These techniques, in combination with traditional methods, have significantly contributed to updating navigational charts with coastline and bathymetric data, to mapping the distribution and types of coastal ecosystems and to monitoring the condition of coral reefs, amongst others.

In some cases, direct detection of ecosystems or species is not feasible with remote sensing techniques, for example due to depth or turbidity. Instead, indirect detection may be possible by observation and modelling of associated sea surface phenomena. For example, changes in ocean colour from blue to green may serve as an indicator of increasing plankton abundance. The green colour is associated with the presence of chlorophyll; the light retaining phytoplankton pigments. Water temperature is another important factor in determining ecosystems and species distribution. Thermal sensors can be used to produce maps of the sea surface temperature, which can be used to identify different water masses and draw boundaries among them.

Credits: Afonso Prestes, 2021

Beyond biophysical techniques

Both in-situ and remote sensing observations are techniques that provide information to map marine ecosystems from a biophysical perspective, i.e., based on biological, physical and chemical features, but they can also be mapped from a social perspective. Highly relevant maps based on human perceptions and socioeconomic knowledge on marine ecosystems can be produced for monitoring and management purposes. As an example, this link gives access to a publication on ecosystem services mapping in the Azores Archipelago, led by our partners from Fundação Gaspar Frutuoso (FGF). Despite not being a MaCoBioS case study area, the FGF team is developing complementary work in this European Union Outermost Region from Portugal, because its natural and social contexts and specificities make it a very interesting hotspot to study and map socio-ecological relationships in the coastal/marine environment.

Furthermore, along with Maynooth University (Ireland), the FGF team is supporting all the MaCoBioS partners in terms of remote sensing data prospecting, processing and analysis, to fill existing gaps in the characterization, assessment and monitoring of the project’s case study areas. The FGF will also set up the MaCoBioS WebGIS platform, an online tool with geospatial capabilities for partners, stakeholders and the general public to visualize and analyse the georeferenced project’s outputs.

Text by Cristina Seijo and Artur Gil

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Climate Change

Salt marshes to fight climate change

Climate change is upon us, and the urgency to act against it has never been so high. The ever-increasing emission of carbon dioxide over the past century must be reversed and has become a global priority. The sea level is rising, and the frequency and intensity of extreme weather events

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Corals: environmental records of the past

Humans are wonderful creatures; our intellect has allowed us to thrive on this planet through impressive technological and scientific advances. However, this success has come at a cost. For example, most marine ecosystems are now under pressure from a variety of stressors mostly linked to human activities. In the case

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What is marine coastal ecological restoration?

Human activities, as well as climatic disasters, are degrading natural habitats, which negatively impacts the entire ecosystem (i.e., the habitat and its associated living organisms of which humans are a part). Such a damaged ecosystem can return to its native state if a restoration program is implemented. This recovery can

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10/18/2021

Exploring Loss and Damage to People and Society from Climate Change impacts on Coastal and Marine Ecosystem Services

Exploring Loss and Damage to People and Society from Climate Change impacts on Coastal and Marine Ecosystem Services

Over the past decades, climate-related hazards, for instance rapid onset events such as floods and droughts, have increased in their occurrence and severity. Simultaneously, slow-onset processes such as sea-level rise and salinization continue unabated, leading to cascading impacts for ecosystems and people. Moreover, the severity of climate change will affect people’s livelihoods, particularly in low-lying areas and Small Island States (SIDS). Given these continuous pressures and disruptions on livelihoods, various people and institutions are discussing and implementing different adaptation strategies. However, adaptation strategies can be sometimes misguided and add negative consequences on current human and natural systems vulnerabilities. Sometimes adaptation to climate change impacts is no longer possible, leading to loss and damage to people and society.

The concept of loss and damage was first mentioned in 2013 under the United Nations Framework Convention on Climate Change (UNFCCC) with the Warsaw International Mechanism on Loss and Damage (WIM). ‘Loss and damage’ does not have a consistent definition, but frequently refers to the unavoidable impacts of climate change due, for instance, to biophysical, social, financial, and technical constraints and the lack of consideration of context-specificities. Loss and damage are characterized as either economic (tradable in the market), such as physical assets, or non-economic (not tradable in the market), such as cultural heritage or ecosystem health and services. For instance, climate induced losses of ecosystem services that coastal communities rely on for their livelihoods and food security, may lead to the displacement of people, resulting in the loss of their identity, heritage, and local knowledge.

There is a need to better understand climate change impacts on ecosystems and their services in order to address loss and damage to people and society.  Within the MACOBIOS project, the focus is on understanding and increasing knowledge about the relationship between climate change, biodiversity, and marine and coastal ecosystem services to support better informed and inclusive decisions, despite the uncertainty posed by climate change impacts.

Through a gender and intersectional lens, I investigate the climate change impact on marine and coastal livelihoods and the limits of adaptation in Martinique. My research pays particular attention to people’s relationship with the ocean and marine and coastal ecosystem services (past, present, and future aspirations) as I seek to understand people’s values and use of these services for their livelihoods and well-being. Furthermore, I explore how people perceive the risks posed by climate change, how they are affected by climate change and why do they act in a specific way to climate change impacts and the resulting loss and damages. This also means considering social group specificities and institutions influencing people’s adaptative capacity.

Consideration of coastal communities’ heterogeneities, dependencies, needs, and priorities is crucial to ensure that science and adaptation policies and projects contribute to minimize and avoid loss and damage. My research will provide a better understanding of adaptation limits and how to address loss and damage induced by climate change on people and societies.  To achieve “The Science We Need For The Ocean We Want” as part of the UN Ocean Decade we must ensure that communities relying on coastal and marine ecosystem services are fully considered in our projects to ensure a more sustainable future.

Description: Itsamia, Moheli, Comoros. Photo credit: Alicia N’guetta

EndNotes

My research also takes place in the context of a Lund University project called Recasting the Disproportionate Impacts of Climate Change Extremes (DICE) that focus on advancing the conceptualisation, measurement, and governance of loss and damage. To learn more please click here.
To learn more please read the article “Climate Change and Ecosystem Services – Implications for Present and Future Loss and Damage to People and  Society” in EcoMagazine-Rising Seas Edition 2021 here.

Text by Alicia N’Guetta

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An ocean of data We are living in the era of “Big data”, where the amount of data has increased and will continue rising exponentially in volume, velocity and variety. Within Marine & Coastal Ecosystems (MCEs), a huge amount of information for environmental monitoring and analysis are collected daily by

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Nature-based Solutions

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The Nature-based Solution concept Our societies are currently facing many challenges. Some are not new, such as food and water security, while others, more recent, are more directly linked to human activities, such as climate change. In this context, Nature-based Solutions, or NbS, provide solutions to these societal challenges by

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Marine and coastal ecosystems

Why are kelp forest important ?

Kelp forests and their importance for nature and society Kelp forests are often regarded as “underwater rainforests”. Formed by the dense growth of several kelp species, they produce a three-dimensional habitat and a highly productive system. Usually found in water temperatures below 20 °C, kelps are large brown algae that

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10/08/2021
Marine and coastal ecosystems

Mapping Marine Ecosystems

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09/30/2021

Understanding power and different worldviews for achieving more just and sustainable coastal adaptation outcomes

Understanding power and different worldviews for achieving more just and sustainable coastal adaptation outcomes

Adaptation has become the centre of Small Island States’ (SIS) political response to cope with the impacts of climate change. Efforts to mainstream coastal adaptation policy among different sectors and improved access to international funds to meet adaptation costs have led to an increase in the number of adaptation projects. For SIS that depend on marine and coastal ecosystems, some interventions such as the construction of coastal protective structures and mangrove and coral restoration are increasingly being promoted as adaptation strategies. However, whilst this should be a cause for celebration, there is growing evidence that current interventions are failing to reduce the vulnerability of those people who are supposed to be supported by these very adaptation actions. But why are current efforts not necessarily reducing vulnerability? And what can we do to overcome these challenges so as to produce outcomes that are just and sustainable?
Fishers in Saint Lucia Photo
credit: Fabiola Espinoza

In this special issue of Eco Magazine -Rising Seas 2021, I unravel these questions by highlighting the role of power dynamics and worldviews in the governance of climate change adaptation. It is common that adaptation goals and priorities are set up and decided upon by people in positions of power, either intentionally, due to political decisions, or inadvertently, due to poorly designed and executed interventions. In doing so, the intended beneficiaries are often left out. For example, the construction of infrastructure as a flood protection strategy has proven to be effective in reducing the vulnerability of SIS to sea level rise, but is frequently implemented by those who have the power to do so, with a particular vision and interest in mind. This affects access to key resources and livelihoods, typically impacting groups who already tend to be marginalized. In this sense, if scientists and policy-makers truly want to reframe adaptation interventions, we must understand how these interventions are interconnected with the wider processes of political and social dynamics. Not only must we must understand ‘who decides what’, but also how values, interests and desired goals are weighted in decision making, and how this can affect the success of adaptation interventions. As the latest IPPC report highlights, with ocean warming, sea level rise and other changes to marine and coastal ecosystems expected to continue in the coming years, coastal adaptation as a policy response to climate change must be prioritized, now more than ever. While this is an indisputable challenge for policy makers and coastal communities, by considering how power and different values, beliefs and worldviews influence the design and institutional interventions of adaptation, we can use this opportunity to rethink current approaches and push for fairer and more equitable pathways.

To read the full article “More than Fixed Solutions: Power and Different Worldviews in Framing Coastal Adaptation Actions” in EcoMagazine-Rising Seas 2021 click here.

Text by Fabiola Espinoza

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Society & Policy

Exploring Loss and Damage to People and Society from Climate Change impacts on Coastal and Marine Ecosystem Services

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09/07/2021

More than Fixed Solutions: Power and Different Worldviews in Framing Coastal Adaptation Actions

More than Fixed Solutions: Power and Different Worldviews in Framing Coastal Adaptation Actions

To read the article

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techniques & tools

eDNA : Unveiling life

The eDNA revolution Everywhere we go, we leave traces of ourselves: our DNA. DNA is a universal molecule, shared by all the living world. When a living being passes through a forest, a lake or a reef, he leaves bits of saliva, urine, or skin… a unique signal of his

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06/04/2021

Climate Change and Ecosystem Services – Implications for Present and Future Loss and Damage to People and Society

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To read the article

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Workshop

Workshop : WP2 Expert engagement

MaCoBioS – WP2 EXPERT-ENGAGEMENT WORKSHOP March 2021, Virtual workshop: Design of the expert-based multi-risk assessment framework – MRAF underpinning cumulative impact appraisal in MCEs”WP2 – T2.1 Risk and adaptation of marine coastal socio-ecological systems <h4>Share this post</h4> Share on facebook Share on twitter Share on linkedin Share on whatsapp Share

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05/12/2021
Our Works

Video : Using eDNA to monitor marine ecosystems

Environmental DNA We have experimented eDNA as a new technique for species and ecosystems monitoring.  As part of the French Coral Reef Initiative (IFRECOR), fish communities have been monitored since 2001 in Martinique (oldest station: Pointe Borgnesse at Le Marin). About 128 species have been observed, counted and size-estimated on

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05/11/2021

eDNA : Unveiling life

Screen Shot 2021-05-11 at 11.50.50

eDNA : Unveiling life

The eDNA revolution

Everywhere we go, we leave traces of ourselves: our DNA. DNA is a universal molecule, shared by all the living world. When a living being passes through a forest, a lake or a reef, he leaves bits of saliva, urine, or skin… a unique signal of his presence in an ecosystem.

Every species has its own DNA sequence. By sampling DNA in an environment, it becomes possible to reveal most species in a given place. That method is called environmental DNA, or eDNA. From viruses to whales, including insects, birds or amphibians, eDNA allows us to unveil the biodiversity present in an ecosystem using only a few samples of water, dirt, honey or feces.

DNA is a molecule shared by all living beings, and eDNA allows us to discover biodiversity as a whole, from small to big animals. On the left, Antillean crested hummingbird (Orthorhyncus cristatus). On the top right, a grouper on a reef in Ponto do Ouro, Mozambique. On the bottom right, a western honey bee (Apis mellifera).
Photo credit: Raphaël Seguin.

We face a massive erosion of biodiversity, where human activities impact all ecosystems on earth. Confronted with the immense challenge of halting biodiversity loss and climate change, our ability to monitor and understand ecosystem changes has never been more important.

Environmental DNA is a revolution in our ability to survey biodiversity.  For instance, eDNA allowed us to detect species that we rarely see with our own eyes, such as the Short-finned Pilot Whale (Globicephala macrorhynchus) in the AGOA Sanctuary of Guadeloupe. It also overcomes bias towards studying only the species we like – like marine mammals – as it reveals indiscriminately popular species such as dolphins or pandas as well as invisible species (viruses, bacteria), or long ignored species (blennies, insects).

eDNA unveils biodiversity undiscriminately, from the ignored and unseen such as the Tompot blenny (Parablennius gattorugine) on the left to the massive and popular humpback whale, on the right.
Photo credit: Loïc Sanchez (photo on the left) and Nacim Guellati (Photo on the right).

In the marine environment, monitoring biodiversity can be highly challenging. Methods such as visual counts during dives or underwater videos often hide some species that are afraid of humans, hidden in the reef or at unreachable depths. However, all of those species, such as sharks or blennies, release DNA in the environment that will be detectable for days.

Be it to study how ecosystems respond to pollution, exploitation, or how species will change their home range facing climate change, eDNA allows us to better understand biodiversity, and helps us to protect it. However, eDNA also has its limits: from this technique we cannot know the number of species in an ecosystem, their age or their sex. That’s why it’s important to combine eDNA with other biodiversity monitoring techniques.

Coastal ecosystems and eDNA

For the MaCoBioS project, we sample multiple habitats using eDNA, from kelp forests to seagrass, coral reefs or salt marshes, all across Europe and the Caribbean Sea.    Our first fieldwork mission took place in Martinique, where we sampled coral reefs and seagrass using eDNA. We sampled while diving: that allows us to filter water close to the bottom and detect hidden species in the reef. Using “eDNA pumps”, we filtrate the water for 30 minutes. The water goes through a filter that keeps all the little fragments of DNA contained in the water. This filter is then sent to Spygen, a laboratory that takes care of analyses and assigns the DNA to a given species. 
In Martinique, eDNA sampling was performed while diving (Top picture) with an eDNA pump. The water goes through a filter that collects the DNA fragments in the water (Bottom picture).
Photo credit: Renaud Leroux.

Monitoring two essential habitats

Seagrass beds are vast underwater prairies composed of long, green leaves. But they’re not algae, they’re flowering plants, just like the ones we find on earth!
Seagrass ecosystems are a nursery for juvenile fish, a food source for herbivores and act as carbon sink.
Photo credit: Umeed Mistry / Ocean Image Bank on the left, and Raphaël Seguin on the right

Coral reefs only cover 0.1% of the oceans…but shelter more than 6000 species of fish. They are among the most threatened ecosystems by climate change.

Coral bleaching are one of the most vulnerable ecosystems in the face of climate change. Raising ocean temperatures are causing widespread bleaching of reefs.
Photo credit: The Ocean Agency / Ocean Image Bank

Humanity has an intricate and interwoven relationship with coral reefs, a relationship that has lasted for thousands of years. This interdependence rests on the functioning of reefs, which depend on the species they shelter. That’s why it’s so important to monitor their biodiversity!

Humanity has a strong relationship with coral reefs.
Photo credit: Grant Thomas / Ocean Image Bank

Facing this crucial challenge, in which the future of millions of human lives is connected to the future of seagrass, corals and the living beings they host, eDNA offers a standardized and easily reproducible universal method thus opening a door to international collaboration on the science of coastal ecosystems. This technique will allow us to understand how these marine and coastal ecosystems respond to climate change, overfishing, and how these pressures affect their functioning and humanity. Understanding these ecosystems will also give us the tools to appropriately choose how to protect them: where to establish marine protected areas? What degree of restrictions should we choose? Which extractive activities are the most destructive to coral reefs?

The MaCoBioS project aims to understand how coastal ecosystems in Europe and the Caribbean respond to human pressures such as climate change, and how to effectively manage them. Environmental DNA, by allowing long-term monitoring of these ecosystems, will help us understand the dynamics of these ecosystems and guide their protection and recovery through this period of planetary warming, in the midst of the Anthropocene.

Text by : Raphael Seguin

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EcoMagazine MaCoBioS-FutureMares

EcoMagazine MaCoBioS-FutureMares

EcoMagazine MaCoBioS-FutureMares

MaCoBioS is featured in the special issue of the EcoMagazine (https://www.ecomagazine.com/magazine) towards the United Nations Decade of Ocean Science (https://oceandecade.com/). The piece discusses how nature-based solutions can be a sustainable way of meeting humans’ needs while protecting and enhancing natural ecosystems. When done well, they can be powerful tools to fight against climate change and protect biodiversity. We are proud to be featured in the special issue along with the project FutureMares.(https://www.futuremares.eu/).

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