Island biodiversity and marine biosecurity in Cabo Verde

Summary

In my view, relationships between the ocean, natural environments and Cabo Verdean society are being transformed by several simultaneous processes.

What are currently the most significant changes in the relationships between the ocean, natural environments and societies in the territory you study? Which seem most consequential in the medium and long term?

In my view, relationships between the ocean, natural environments and Cabo Verdean society are being transformed by several simultaneous processes. These are not simply isolated environmental changes, but a combination of mutually reinforcing ecological, economic, social and institutional pressures.

The first transformation concerns the climate and oceanographic system. Rising sea temperatures, acidification, sea-level rise, changes in marine productivity, increasingly irregular weather and more intense extreme events directly affect coastal ecosystems, fishery resources and the communities that depend on them. In small island states such as Cabo Verde, these effects tend to be particularly severe because land territory is limited, population and infrastructure are concentrated along the coast, and there is strong dependence on marine resources. The IPCC, the Intergovernmental Panel on Climate Change, emphasises that changes in ocean temperature, sea level, extreme events, oxygenation and acidification directly affect fisheries and other marine resources on small islands.

The second transformation is the intensification of coastal and maritime uses. Urban growth, tourism, ports, shipping, aquaculture, exploitation of fishery resources and expanding coastal infrastructure increase pressure on already fragile habitats. In Cabo Verde, this pressure is particularly visible in port areas, urbanised zones and places where economic and recreational activities are concentrated.

The third transformation concerns the way fisheries operate. Artisanal fishing remains enormously important to Cabo Verde economically, nutritionally, culturally and socially, but faces changes in resource availability, distribution and abundance. Overfishing, illegal fishing, bycatch of vulnerable species, habitat degradation and climate change can act simultaneously. Fishers therefore face not only reduced catches, but growing ecological and economic uncertainty.

The fourth transformation is biodiversity loss and fragmentation. This results from the combination of habitat destruction, pollution, introduced alien species, human disturbance, accidental mortality and climate change. The problem is compounded by Cabo Verde's island ecosystems, isolated populations and species with restricted distributions. The national biodiversity strategy has already identified reducing pressures, conserving priority habitats, restoring ecosystem resilience and strengthening knowledge and monitoring among its priorities.

The fifth transformation is the growing movement of organisms through trade and maritime transport. Ports, marinas, vessel hulls, ballast water, sediments and other materials can transport non-indigenous species. National reports identify ports and airports as important entry points for introduced species and highlight ballast water as a particular concern for the marine environment.

In the medium and long term, I consider three transformations particularly consequential for Cabo Verde.

Climate and oceanographic change, because it modifies the physical conditions that determine ecosystem distribution and productivity.

The reorganisation of the blue economy, because it will determine which uses of maritime space are promoted, regulated or restricted.

Institutional capacity to integrate science, enforcement, community participation and spatial planning.

Cabo Verde's future will depend less on choosing between conservation and development than on the capacity to build a development model that recognises the archipelago's ecological limits.

How do these changes redistribute vulnerabilities, resources and land uses? Which groups, activities or ecosystems benefit, which become more exposed, and what choices or conflicts result?

These changes simultaneously redistribute risks, opportunities, resources and decision-making capacity. Not all social groups face the same consequences, and not all participate equally in decisions about territory and the ocean. Artisanal fishers are among the most exposed groups. They depend directly on resources that may become more variable, face rising operating costs and have less financial capacity to absorb periods of low catches. Furthermore, when new activities occupy coastal areas traditionally used for fishing, they may lose access to important areas without adequate compensation.

Coastal communities are also exposed to erosion, flooding, deteriorating water quality and the loss of protective habitats. Beaches, dunes, wetlands, reefs and other coastal habitats have more than ecological value: they contribute to coastal protection, fisheries, tourism and people's safety.

Certain sectors, meanwhile, may benefit from an expanding blue economy. Coastal tourism, ports, maritime transport, marine renewable energy, aquaculture and other activities can generate jobs and revenue. Benefits, however, are not automatically distributed equitably. There is a risk of privatising benefits while socialising environmental costs: some actors profit while communities bear lost access, pollution or resource degradation.

The most exposed ecosystems combine high ecological importance, restricted distribution and intense human pressure. They include coastal habitats, reefs and benthic communities, nesting beaches, turtle and seabird feeding grounds, fish spawning and nursery areas, and habitats of endemic or threatened species.

Migratory species also face risks that extend beyond national territory. Seabirds, turtles, cetaceans, sharks and other organisms use areas across several countries and ocean regions. A conservation measure adopted in one place may be insufficient if threats persist elsewhere in their life cycle. These changes generate conflicts between conservation and infrastructure expansion; artisanal and industrial fishing; tourism and community access to the coast; resource exploitation and ecological integrity; protected-area creation and the continuation of traditional activities; and short-term interests and long-term resilience.

In my opinion, the central question is not simply who uses the territory, but who decides, with what information and responsibilities, and through what mechanisms for distributing benefits and costs. Marine spatial planning must therefore be participatory, evidence-based and capable of recognising local communities' rights, needs and knowledge.

How does Cabo Verde's insularity influence species' genetic diversity and ecosystems' vulnerability to rapid disturbances?

The experience that should contribute more to international debates is that of communities living daily with ocean variability and the concrete limits of an island territory. International debates are often dominated by large models, global indicators and technological solutions, while local experiences are treated merely as supplementary information.

Fishers, for example, observe changes in when species occur, the location of shoals, sea conditions, winds, currents, breeding areas and the relationship between oceanographic conditions and fishing success. This observation develops over many years and has a spatial and temporal resolution not always present in conventional scientific programmes.

I also consider the experience of local institutions, community associations, NGOs and technical staff working with limited resources insufficiently heard. These actors know the practical difficulties of implementing environmental policy in an archipelago: inadequate enforcement capacity, difficulties travelling between islands, scarce data, staff turnover, laboratory limitations and the need to reconcile conservation with immediate economic needs.

My work experience leads me to defend a simple idea: conservation cannot be built solely through producing knowledge; it must also produce trust, participation and local capacity. A protected area may formally exist, but will remain fragile if communities do not understand its objectives, participate in its management or benefit from the opportunities conservation can generate.

Cabo Verde can contribute an important international perspective on managing biodiversity, fisheries and climate adaptation under conditions of insularity, limited resources and heavy ocean dependence. Cabo Verdean experience shows that conservation in small island states must be participatory, but with clear responsibilities. Local knowledge should not be used solely to legitimise decisions already made. It should help define problems, select indicators, interpret results and evaluate management measures.

How does Cabo Verde's insularity influence species' genetic diversity and ecosystems' vulnerability to rapid disturbances?

Cabo Verde's insularity influences genetic diversity through several mechanisms. In many cases, geographic isolation reduced gene flow between island populations and between the archipelago and mainland populations. As a result, island populations became genetically differentiated over time, especially in species with limited mobility.

Islands also tend to support smaller populations. Small populations are more sensitive to genetic drift, the random loss of genetic variants between generations. They may also experience population bottlenecks, inbreeding and reduced genetic diversity. These processes limit their ability to adapt to disease, climate change, new environmental pressures and changes in food availability.

However, Cabo Verde's insularity has not produced the same result in every case. Among marine species with high dispersal capacity, such as certain fish, turtles, cetaceans or organisms transported by currents, gene flow remains relatively high. Cabo Verde also lies in an ocean region influenced by currents and the movement of organisms through the Atlantic, which has enabled connectivity within Macaronesia and with the Mediterranean.

Insularity can also promote differentiation and endemism. When a population remains isolated for long periods, it may accumulate distinctive genetic and ecological characteristics. This increases its conservation value even when the species occurs in other regions.

Vulnerability to rapid disturbance arises when a population has a restricted distribution, small size and limited connectivity. A local disturbance, such as intense overfishing, disease, a pollution spill, habitat degradation or the introduction of a predator, can affect a large proportion of the total population. Connected populations can experience recolonisation or demographic rescue through immigration. In isolated populations, recovery may be much slower or even impossible. Genetics can therefore inform concrete decisions: which populations should be treated separately, where to create protected zones, which populations need recovery, and whether moving individuals is appropriate or may create genetic risks.

Which invasive species are currently of greatest concern, and what scientific or institutional difficulties limit their monitoring and control?

I would be cautious about presenting a definitive list of the "most concerning species", because priorities depend on taxonomic confirmation, distribution, abundance, capacity to spread and observed impacts. Cabo Verde still has substantial inventory and monitoring gaps. Priorities should therefore be defined by functional groups, introduction pathways and high-risk locations.

In the marine environment, ports and marinas should be priority sites. In a study conducted in the northern archipelago, I found 11 non-indigenous species, mainly in Mindelo Marina, Porto Grande and other locations associated with port activity. This indicated greater richness and diversity of non-indigenous species in ports and marinas than at natural sites.

Groups requiring attention include fouling organisms transported on vessel hulls, such as ascidians, bryozoans, sponges, algae and other invertebrates associated with port structures. Organisms, including rapidly colonising macroalgae, can also be transported in ballast water and sediments. On land, concerns involve rodents, cats, dogs and monkeys, as well as insects and pathogens associated with trade and the transport of plants and animals.

Introduced predators are particularly significant on islands because seabirds nesting on the ground or in small colonies are vulnerable. Cabo Verde's endemic birds face threats including invasive predators, habitat degradation, light pollution, human disturbance and fisheries bycatch.

The main scientific difficulties concern the absence of a complete baseline for local biodiversity; distinguishing native, introduced, cryptogenic and recently established species; a shortage of specialist taxonomists; and insufficient time series to track population changes. Further constraints include identifying larvae and small organisms, detecting invasions early, inadequate data on ecological and economic impacts, and limited integration between port observations, academic research and existing databases.

Genetics and environmental DNA can significantly improve species detection and identification, but they do not replace taxonomic knowledge or confirmation through specimens, images or other complementary methods. Institutional difficulties include fragmented responsibilities, a lack of continuous enforcement, limited coordination between ports, environment, agriculture, fisheries and health sectors, and insufficient human, technical and financial resources for a rapid response.

How can biodiversity inventories and genetic data be translated into concrete conservation and spatial planning decisions?

Biodiversity inventories are useful for conservation only when they answer management questions. An inventory should not be seen as a static species list, but as a basis for identifying important areas, tracking trends, assessing threats and setting priorities. The first step is to turn data into maps of distribution, abundance, richness, endemism, rarity, connectivity and threats. These maps can support the designation or expansion of protected areas, identify breeding and feeding zones, or locate ecological corridors.

It is important to move from a presence-or-absence approach to an indicator-based approach. For example, a decision to protect an area should consider not only the number of species recorded but also endemic species, the habitat's ecological function, connectivity, vulnerability and importance to communities.

Genetic data add dimensions that conventional inventories cannot reveal. Two populations may look morphologically similar while being genetically differentiated. Conversely, geographically separated populations may have high connectivity. Genetics can help identify isolated populations, management units, levels of gene flow and the presence of cryptic species.

If genetic analysis shows that a threatened species' population has low diversity and limited connectivity, the decision may be to protect breeding habitat, reduce adult mortality, introduce connectivity measures or carefully assess population reinforcement. This does not necessarily mean transporting individuals from another island. Such a decision would require assessment of genetic compatibility, disease transmission risks and possible disruption of local adaptations.

Similarly, if an inventory reveals a high concentration of non-indigenous species in a marina, this should lead to concrete measures in biosecurity, vessel inspection, hull cleaning, ballast water management, operator training and regular monitoring.

The ultimate aim is to establish a clear chain between data, interpretation, decision, implementation and evaluation.

What knowledge held by fishers, farmers or local communities could complement scientific methods of biodiversity observation?

The knowledge of fishers, farmers and local communities can complement science in several ways. Its value lies not merely in providing occasional observations, but in preserving ecological memory series that may span decades.

Fishers can provide information about traditional fishing grounds and changes in fish abundance and size. Seasonal changes, breeding periods and the presence or absence of rare or uncommon species can be valuable for resource management. Farmers and herders can help explain changes in plant distribution, flowering and fruiting periods, the presence of invasive species and important aspects of soil erosion and degradation.

At the land-sea interface, coastal communities can provide rapid, accurate information about coastal ecosystem dynamics. Many strandings of large organisms and turtle nesting events are first reported by residents who frequent coastal areas. This knowledge should be integrated through rigorous methods, including semi-structured interviews, participatory mapping, logbooks, community monitoring, georeferenced photography and simple digital platforms. Citizen science can be especially useful for detecting invasive species. Programmes involving divers and local operators, for example, have already demonstrated the capacity to produce new records and expand monitoring's spatial coverage.

The aim is not to replace scientific methods with local knowledge, but to establish complementarity. Science can offer standardisation, statistical analysis, molecular identification and regional comparison. Communities can offer temporal continuity, knowledge of microhabitats, contextual interpretation and the capacity to detect changes occurring between scientific campaigns.

What forms of regional and international cooperation would be most useful for strengthening biosecurity and scientific capacity in small island states?

For small island states such as Cabo Verde, regional cooperation should be practical, stable and directed towards lasting capacity, rather than only short-term projects. The most useful cooperation leaves infrastructure, skills, protocols, databases and trained professionals in the country.

First, it would be important to develop a regional marine biosecurity network involving Macaronesia, West Africa and other small island states. This network could harmonise protocols for sampling, identification, risk analysis and responses to invasive species.

Second, countries should share information about ships, ports, marinas and introduction pathways. Data on species detected in one port can help anticipate risks in other ports in the region. A regional platform could integrate records of non-indigenous species, images, genetic barcodes, reference samples and early-detection alerts.

Third, laboratory capacity must be strengthened. Not every country needs to have every technique immediately, but the region should have reference laboratories for classical taxonomic identification and barcoding, to detect both indigenous and non-indigenous biota. Cooperation has supported sample exchanges, technical training, mobility programmes, joint student supervision and collaborative research. Cabo Verde's universities have played a fundamental role in training technicians and researchers who remain connected to national issues.

In my view, regional cooperation should also support enforcement and the implementation of international conventions. For ballast water, for example, formal accession is not enough: trained inspectors, sampling equipment, laboratories, legal procedures and port coordination are needed.

I also consider four forms of cooperation essential.

Scientific cooperation, to produce knowledge and develop methods.

Institutional cooperation, to harmonise legislation, enforcement and data sharing.

Financial cooperation, to guarantee continuous monitoring rather than isolated projects. Community cooperation, to involve fishers, port operators, farmers, NGOs and schools.

International cooperation should avoid a relationship based solely on technology transfer. Cabo Verde needs access to equipment and funding, but it also needs to participate in defining scientific questions, managing data and interpreting results.

In my opinion, the priority should be to build a cooperation architecture combining three levels: strong national capacity, functional regional networks and predictable international support. Only then can Cabo Verde move from being a territory that receives external answers to an active partner in knowledge production and Atlantic governance.

Bibliographic information

Type

Article

Date

14 October 2026

Author

Evandro Pires Lopes

Study Centre

ONS

Original language

English

Original document

PDF, 6 pages

Full text

Transcription of the original document

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