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Marine Turtles, Ecosystem Services and Human Welfare in the Marine Ecosystems of the Caribbean Sea: A Discussion of Key Methodologies

Les tortues marines, les services écosystémiques et le bien-être de l'homme dans les écosystèmes marins de la mer des Caraïbes : un examen des méthodologies
Sonja S. Teelucksingh, Scott Eckert et Paulo A.L.D. Nunes

Résumés

La préservation de la biodiversité est d'une importance fondamentale pour le maintien des moyens de subsistance de l'homme. L'un des atouts majeurs de l’ensemble régional que constitue l'Amérique latine et les Caraïbes (LAC) demeure sa richesse biologique, par extension, toute dégradation de sa biodiversité pose des problèmes environnementaux d’ordre mondial. Les ressources marines de la mer des Caraïbes, qui sont particulièrement menacées, sont d'une importance économique, écologique et sociale vitale pour la région. Les tortues marines jouent un rôle essentiel dans la mer des Caraïbes à la fois en termes de fonctions écologiques et de bien-être humain.
En ce sens, les efforts de conservation peuvent de la capacité de chiffrer la valeur sur le bien-être des changements associés à la perte de biens et de services des écosystèmes dans lesquels la biodiversité est partie intégrante. En utilisant les catégories de services des écosystèmes du Millennium Ecosystem Assessment, la présente étude aborde, dans une perspective interdisciplinaire, les méthodologies associées aux interrelations entre les tortues marines, les services écosystémiques et le bien-être de l'homme.
Si le principal avantage économique actuellement identifié repose sur le potentiel écotouristique, autour des sites de nidification des tortues, pour une image fidèle des ressources environnementales sur lesquelles ce service repose, il est nécessaire d'identifier également les autres apports de la ressource, en termes de régulations, de services culturels. De cette façon, les impacts sur le bien-être humain peuvent être mieux appréhendés et les ressources peuvent être gérées de façon plus efficace.

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Introduction

1It is increasingly recognized that maintaining biodiversity is of fundamental importance toward sustaining human livelihoods. High and sustained levels of biodiversity give ecosystems resilience to perturbation and this enhanced stability enables opportunities for sustained exploitation by human populations. Notwithstanding this recognition, reduction in biodiversity continues and has been termed the “central environmental challenge of our time” (Levin 1999, Polasky et al., 2005, Millennium Ecosystem Assessment 2005 [2]).
The international treaty known as the Convention on Biological Diversity (CBD) was created in an attempt to rise to this challenge. The CBD states three objectives: the conservation of biological diversity, the sustainable use of its components, and the fair and equitable sharing of the benefits arising out of the utilisation of genetic resources (OECD 1999). The realisation of these objectives can often depend on the ability to place a value on welfare changes associated with the loss of ecosystem goods and services into which biodiversity plays an integral role. However, valuing biodiversity can be complicated and difficult to do in a comprehensive manner. With a variety of available definitions and value perceptions spanning scientific disciplines and levels of aggregation, an insufficient knowledge of the mechanisms of transfer between biodiversity and human welfare, the existence of direct and indirect drivers of change at varying spatial and geo-political levels, and an inevitably broad range of stakeholders with often conflicting objectives, the multi-dimensionality of valuing biodiversity is synonymous with its complexity (OECD 1999). Notwithstanding it is essential that, as the foundation of effective environmental management, we attempt to assess the relationships between biodiversity and human well-being – and apply the multiplicity of economic valuation tools that have been created to undertake this challenge.

2Most of the world’s biodiversity “hotspots” are found in the developing world (Myers et. al 2000). Indeed, one of the major assets of the region identified as “Latin America and the Caribbean” (LAC) is its biological wealth (Global Environment Outlook 2003). By extension, the continued biodiversity loss of the LAC region is seen as one of the world’s principal environmental problems. The Small Island Developing States (SIDS) are seen as particularly vulnerable to biodiversity loss (Global Environment Outlook 2003) and environmental degradation (van Beukering et. al 2007). SIDS generally share a number of economic and environmental characteristics that make them highly vulnerable to exogenous impacts (Mc Elroy et.al. 1990, Bass 1993, Global Environmental Outlook 2003, van Beukering et. al 2007, Ghermandi et.al 2009, Teelucksingh and Nunes 2010, Teelucksingh and Perrings 2010). They are highly affected by changes in the natural environment, such as those caused by climate change, because much of the land is coastal with terrestrial and marine ecosystems closely linked. Small human populations are coupled with high population densities concentrated in those coastal areas, thus environmental changes affect a larger fraction of the human populations that might otherwise be the case. SIDS also have a heavy reliance on natural resource exploitation, with many of the SIDS relying primarily on tourism-oriented economies (with coastal tourism of particular importance). Such lack of diversity in economic inputs leave SIDS nations highly vulnerable to unstable economic performance. Finally SIDSare highly dependent on the developed world for the absorption of exports and as source of imports, implying also a high degree of vulnerability to external economic conditions. The special case of SIDS is recognised by the United Nations, who categorise SIDS as its own category in its developmental agenda (UN Desa 2007).

3The large-scale marine ecosystem of the Caribbean Sea is under particular threat, and this constitutes a further risk for regional SIDS. For many small islands the marine environment can be the most important economic resource (Bass, 1993). It is commonly accepted that the marine resources available to island states can, if properly utilised, significantly contribute to the sustainable development of the region (Dolman, 1990, FAO 1999). If marine resources are left unmanaged or at best managed in a less than holistic sense, it is the poorer, rural coastal communities of the small island economies of the region and their future generations who will suffer the most (Dhoray and Teelucksingh, 2006). The marine resources of Caribbean Sea are of vital economic, ecological and social importance to Caribbean SIDS and to the LAC region.

4Shared marine resources combined with economic, geographical and political heterogeneity can create significant challenges for regional cooperation and management. In this context, there is the increasingly urgent need for research into the linkage between biodiversity and economics at the regional level. Regional heterogeneity fosters a regional disconnect. In addition, with respect to marine resources there can exist a broad range of stakeholders with conflicting objectives. Furthermore, biodiversity valuation itself is accompanied by certain complexities. There are a variety of available definitions of biodiversity (species, genetic, ecosystem function), with different implications for impacts on the provided ecosystem goods and services. Economic valuation techniques have their own challenges, in particular in the context of developing countries. Once valuation exercises are undertaken, the question becomes how to embed these values into the decision making processes, and implement these policy measures taking into account the economic peculiarities of the region.

1. Marine Turtles in the LAC

5Marine turtles play vital roles throughout the Caribbean Sea both in terms of ecological functions and human welfare. While sea turtles have existed for more than 120 million years, modern sea turtle species first appeared 25 - 90 million years ago and in some cases are as old as the habitats in which they thrive. Such an ancient evolutionary history has led to the close integration between these species and their environment, an integration that has led to turtles becoming valuable participants in sustaining the stability of marine ecosystems.

Table 1. The Marine Turtles of the LAC

Spécies

IUCN Status

Primary Nesting Location(s)

Loggerhead

Caretta caretta

Endangered

South Florida, USA, Mexico

Green

Chelonia mydas

Endangered

Costa Rica, Venezuela (Aves Island)

Leatherback

Dermochelys coriacea

Critically

Endangered

Trinidad and the Guianas

Costa Rica/Panama

Hawksbill

Eretmochelys imbricata

Critically

Endangered

Mexico, Barbados, Puerto Rico

Kemp’s Ridley

Lepidochelys kempii

Critically

Endangered

Mexico

Olive Ridley

Lepidochelys olivacea

Endangered

Suriname, Fr. Guiana

Source: adapted from Dow et al., 2007

  • 1 Only the flatback (Natator depressa) is not found in the LAC, this species is endemic to Australia.

6Six of the seven global species of marine turtles are found in the LAC region1. All life stages of each species spend some time in the region. These life stages include reproductive (mature adults and eggs), oceanic juvenile, neritic juvenile, subadults and adults. Movements and migrations through the region and across national jurisdictions are common. Turtles are resident in virtually all habitats including coastal reefs, sea grass meadows and oceanic waters. As Figure 1 demonstrates, nesting habitats occur all over the LAC region.

Figure 1. Sea Turtle Nesting in the Caribbean

Figure 1. Sea Turtle Nesting in the Caribbean

Source: Dow et al., 2007

7Within this context effective regional management of the resource requires a regional approach. However, the regulatory profile of the LAC with respect to marine turtles is described as “fragmented”; Dow et.al provide an excellent review of the heterogenous legislative structures surrounding marine turtle protection in the region (Dow et. al 2007). Thirty (69.8%) nations and territories prohibit sea turtle exploitation year-around: 29 of 43 jurisdictions mandate indefinite protection (eight of these allow exemptions for ‘traditional’ exploitation), while Anguilla has adopted a moratorium set to expire in 2020. With the exception of the Cayman Islands, legal sea turtle fisheries are based on minimum size limits (by weight or shell length), targeting large juveniles and adults in contradistinction to the best available science on management and recovery.
Of the 43 nations and territories examined by Dow et.al (2007), 29 have legislated indefinite complete protection for sea turtles; in addition to these, Anguilla has adopted a moratorium set to expire in 2020. Eight of the 30 nations and territories, including Anguilla, where sea turtles are protected year-around, provide for exceptions relating to “traditional” or “subsistence” exploitation (Brautigam and Eckert 2006). Thirteen nations and territories operate under regulatory regimes that leave one or more species seasonally subject to exploitation. In summary, legislative and management structures surrounding marine turtles in the LAC are undertaken through national rather than regional umbrellas, and these structures are not consistent.

2. Ecosystem Engineers

8Marine turtles have a number of important biological characteristics that contribute to their capacity to sustain or influence the habitats where they live. They are large bodied marine vertebrates, with adult turtles ranging in size as from 100 – 900 kg depending on the species. Such large size gives them the capacity to manipulate physically their surroundings and to travel great distances. Sea turtles are highly migratory, and can range many thousands of km during development or for breeding. They are also well distributed throughout the Caribbean, and found living in virtually all environments of the region. As poikilotherms energy consumed by marine turtles is used primarily for growth and reproduction rather that heat generation as is the case for homeotherms. Thus, they only require small amounts of food relative to their body size, and can thrive at high densities on low-energy food sources or survive for long periods at reduced nutritional uptake. Nonetheless, as large animals living at high density, their food uptake can be extensive.

9The green turtle (Chelonia mydas) is a large (adults exceed 300kg), herbivorous species that inhabits near shore environments where they forage on sea grasses (e.g. Thalassia testudinum or turtle grass) and a variety of algae species. Sea grass meadows are critically important to Caribbean ecosystems as they are highly productive, provide important nursery areas for fish and invertebrate species, and help stabilize the sea floor between coral reefs and the surf zone.
It has been estimated that the Caribbean supported between 33 – 39 million green turtles prior to European settlement 500 years ago
(Jackson, 1997) . The density was so high that it is noted that Columbus complained that navigation in Caribbean bays was hampered by the density of green turtles. In their chapter on the ecological roles of sea turtles, Bjorndal and Jackson (2003) describe how such a large population of green turtles might have affected near shore environments of the Caribbean. They note that seagrass meadows that have been grazed regularly exhibit a general shortening and thinning of grass blades. This shortening causes a decrease in the capacity of sea grass meadow to entrap particles, and reduces substrate recruitment thereby causing “substantial” changes in physical structure of near shore habitats. Shortening and thinning of the grass blades also reduce self-shading; temperature; sulfide levels; hypoxia and infection by slime molds, factors that can damage the health of the seagrass meadow.

10It is considered that green turtles serve to remove older, less productive seagrass biomass, reduce that material to fertilizer (though digestion) and redistribute that fertilizer throughout the habitat. This cropping and fertilization serves to increases the vigor of the sea grass meadows so provides an overall health benefit to the habitat.
Hawksbill sea turtles (
Eretmochelys imbricata) also provide an important ecological role to Caribbean reef ecosystems. Hawksbills are coral reef residents, spending their large juvenile or adult lives in reef habitats. Diet for the species is rather unique as they consume primarily sponges (Leon and Bjorndal, 2002; Meylan, 1988; Meylan et al., 1985; Meylan and Ruetzler, 1990; van Dam and Diez, ; Van Dam and Diez). Sponges can have a higher biomass than corals (Goreau and Hartman, 1963; Ritzler 1978 in Bjorndal and Jackson 2003) and compete with corals for space in reef habitats. While hawksbills forage selectively on sponge fauna, studies of hawksbill diet regularly identify Chondrilla nucula otherwise known as the liver sponge as common in hawksbill diets. This encrusting sponge is also cited in studies of reef space competition, and has been identified as the antagonist in as many as 70% of all coral overgrowth events (Hill, 1998) in some places of the region. It appears that hawksbills play an important role in maintaining species diversity in Caribbean reef habitats by reducing sponge populations so that reef species diversity is maintained.

11For other Caribbean sea turtle species such as the loggerhead (Caretta caretta), olive ridley (Lepidochelys olivacea), Kemp’s ridley (Lepidochelys kempii), and leatherback (Dermochelys coriacea) their influence in marine ecosystems is less well defined. For some, actions to the physical environment have been proposed may be important. For example loggerhead sea turtles have been shown to practice infaunal mining in search of prey (Preen, 1996). While this behavior has only been observed in SE Queensland, Australia, it is likely to occur in the Caribbean as well. Loggerheads use foreflippers to dig pits up to 0.45 m deep and up to 8 m long in search of prey. Such infaunal mining could conceivably create fresh substrate or restructure benthic communities.
For other species, influence on the environment may come in their role as predators as described earlier for green and hawksbill.
Leatherbacks (Dermochelys coriacea) are obligate jellyfish consumers and consume large numbers of jellyfish (James and Herman, 2001) possibly even their own weight in jellyfish daily (Lutcavage, 1986). Jellyfish play an important role in structuring marine food webs and can act as apex predators in those systems. In some cases overfishing or other large ecosystem perturbations have actually served to allow jellyfish to dominate those ecosystems and resist a return to vertebrate dominated environment (Brodeur et al., 2002; Daskolov, 2002; Lynam et al., 2009; Mills, 2001). Such a shift to invertebrate dominated ecosystems threatens commercial fishery resources. As one of the only obligate jellyfish consumers, it is likely that leatherbacks play a role in preventing such shifts.

12Against this background, we can interpret the influence of these marine turtles on marine ecosystems as that of “ecosystem engineers”, that is, their interaction with and influence on their physical habitats. However, besides the direct action of sea turtles on their environment, there are other and more subtle means by which sea turtles influence marine ecosystems. One of the most intriguing is how sea turtles serve to provide marine nutrients back into terrestrial ecosystems. Nutrient flow between terrestrial and marine ecosystems is generally unidirectional. Nutrients and minerals from land are washed into the sea by rain and rivers and are sequestered into marine food webs through a number of mechanisms such as phytoplankton production. Rarely are there opportunities to move nutrients in the reverse direction from the marine environment to land ecosystems. However, one study measured that more than 70% of energy and nitrogen contained in sea turtle eggs returns to the sea in the form of living turtles (Bouchard and Bjorndal, 2000). Most of that energy remained on land, as unhatched eggs, shells or incorporated into terrestrial (and avian) egg and hatchling predators. When it is considered that marine turtles average between 80 – 160 eggs per clutch (depending on the species), and average 2 – 6 nests per season (again depending on the species), and that millions or even billions of sea turtle eggs are laid on Caribbean nesting beaches each season, it can be imagined that sea turtles return an extraordinary amount of nutrients return to the land.

3. Marine Turtles, Ecosystem Services and Human Welfare

13As with all environmental goods and services, we can identify linkages between the ecosystem goods and services provided, and human welfare. The MEA categorises the ecosystem goods and services provided by ecosystems into 4 groups: provisioning, regulating, cultural and supporting (MEA 2005[1]).
Table 2 below represents an initial attempt to map each of these services to marine turtles in the LAC region in terms of the magnitude of the particular service to human welfare.

Table 2. Marine Turtles and the MEA Services

Category of Service

Ecosystem Goods and Services provided by the turtle community in the LAC

Provisioning

Food

Fiber, timber, fuel

Medicines, other resources

Eco-Tourism

Regulating

Biological regulation

Freshwater storage and retention

Hydrological balance

Atmospheric and climate regulation

Human disease control

Waste processing

Flood/storm protection

Erosion control

Cultural

Cultural and amenity

Recreational

Aesthetics

Education and research

Supporting

Biochemical

Nutrient cycling and fertility

Source: adapted from MEA[1]

14In addition, by general economic activity, human beings can also adversely impact sea turtle resources and can jeopardize the sustained utilization of those resources. Such impacts or drivers of change can occur through direct consumption or use, as well as indirectly through environmental stresses such as climate change or habitat destruction. In terms of specific threats to marine turtles, it is possible to distinguish between threats to nesting (on beaches and in nearshore waters near nesting beaches), and threats to turtles on foraging grounds or during migration (away from natal nesting beaches). Threats to nesting can often be effectively dealt with at local levels by community and national actions on nesting beaches or within waters under national jurisdictions. Threats away from nesting areas, such as in open waters migration routes or within other national jurisdicitons can be more difficult to manage since they require multilateral actions within other national jurisdictions and in international waters .

15The identification of ecosystem services, the quantification of the contribution of any species or groups of species to these services, and the feedback effects of the utilisation of these services on the very natural environment from which they come, fall to a multitude of disciplines including economics and ecology. Ecology can define how the resource interacts and supports its environment, as well as the regulatory feedback mechanisms that determines the size of the resource, while the economic analysis can place dollae value to the anthropogenic use of the resource, or the environment supported by the resource and the cultural assessment provides anthropogenic value to the resource. Once identified, disciplines can work together to estimate the magnitude of their impacts in terms of human welfare changes.
The economic valuation of environmental resources follows four general steps (see Figure 3 below).

Figure 3. The Process of Environmental Valuation

Figure 3. The Process of Environmental Valuation

16Given an environmental resource that is to be valued, the first task is the identification of the particular environmental service to be valued in terms of the particular ecosystem service category. Any valuation technique must be seen in the context of the component of the biodiversity service being measured. The concept of Total Economic Value (TEV), which compartmentalises biodiversity value into use values and non-use values.has now given way to the MEA framework of Ecosystem Goods and Services , where values are now disaggregated into provisioning, regulating, cultural and supporting services. The economic valuation exercise is to disaggregate environmental resources into the different types of services that they provide (Table 2). From this, it is possible to adopt various valuation tools and techniques (both economic and non-economic) in an attempt to monetise these services. Once this is complete, policy prescriptions, and implementations, must follow. If properly implemented, this leads to a feedback to the biodiversity service in terms of the better resource management that results.
Whichever framework is adopted, some of the economic valuation methodologies are more capable of revealing the values of some of these service subsets rather than others (Nunes and van den Bergh 2001). Furthermore, it is undeniable that, no matter the technique, some of these values themselves in the context of human welfare are by definition notoriously difficult to reveal. For this reason many scientists have despaired of valuing biodiversity and many criticisms surround the ones who have made the attempt (Nunes and Van den Bergh 2001, Wilson and Howarth 2002, Howarth and Farber 2002, Brito 2005, Hoffman and Hoffman 2008).

  • 2 Paran and Williams (2007) provide a thought-provoking discussion on the validity of even the catego (...)

17The picture becomes more complex by the socio-economic context in which valuation efforts are attempted. Much of the world’s biodiversity “hotspots” are located in the developing world (Gossling 1999, Myers et. al 2000, O’Connor 2008). The Millennium Development Goals explicitly recognise “sustainable development” of developing countries2 as a target, with valuation viewed as a fundamental aspect of this notion (Georgiou et. al 1997). While the methodological techniques of valuing and managing biodiversity have largely been created context-free, and their applications are to be found mainly in the developed world (Christie et. al 2008), the relative richness of biodiversity in the developing world and its unprecedented rates of loss mean that research focus must be intensified on these countries (Ninan and Sathyapalan 2005, Christie et al., 2008).
It is essential that we understand and assess the interactions between biodiversity and human well-being in the very countries and regions that are both directly determining its loss by explicit economic decision-making and may also bear the brunt of the consequences of such loss. However, it is increasingly accepted that environmental management practices, and the environmental valuation that necessarily precedes this, cannot be imported wholesale from the developed to the developing world (Turnbull 2004). Any valuation and management exercise should always be cast within the mould of the economic, sociological, political and cultural characteristics and peculiarities of the study site within which it is located. Such characteristics determine the interactions between the local populations and the environment, can affect the use of valuation tools, and can hinder the efficacy of policy outcomes based on such measurements; in other words, they affect every stage of the valuation exercise. The underlying objective of any economic valuation exercise is to ensure that the policies that are implemented result in an improvement of the characteristics which, by affecting how biodiversity is viewed and utilised, can in increments lead to the sustainable use of the biological resources. However, valuation studies that are framed without a cognizance of the local and developmental context

18The arguments for conservation of marine turtles in the LAC region can best be motivated by the arguments of the benefits of these species to human welfare, through their contribution to the ecosystem goods and services such as those identified in Table 2 above. One of the provisioning services identified is that of eco-tourism. There is a close link between the biodiversity endowment of a country and its potential for ecotourism development. Eco-tourism, as one of the services provided by biodiversity, is often viewed as effective for promoting the conservation of endangered species and habitats in developing countries. There is an existing and potential role of marine turtles in regional SIDS and the LAC in the eco-tourism industry, with areas such as Grande Riviere and Matura in Trinidad already prime destinations for activities such as these. Community-based development of an eco-tourism industry surrounding marine turtles in the LAC is a potential contributor to sustainable development, with the possible “win-win” factors of biological conservation and economic enhancements.

Conclusions

19In the conservation effort of marine turtles in the LAC, three things become clear. Firstly, these efforts need to be integrated into a regional plan that facilitates regional policy making on a shared resource. Secondly, we need to properly identify the services provided by marine turtles to human welfare. Thirdly, we need to estimate the monetary values of these services in order to better argue their conservation.
These all require the joint efforts of economists and ecologists. It is necessary to properly map the contribution of marine turtles to each of the categories of the ecosystem goods and services. Once this is done, there is the need to identify appropriate valuation methods for each type of the MEA services. As most valuation studies are located in the developed world, there is the need to adapt methods to developing country pecularities and to local cases where necessary. For eco tourism, it is possible to use market-based methods. However, for the other non-marketed services provided by the species, a hybrid approach of environmental valuation methods may be necessary to account for the local developing country pecularities.
In order to better conduct economic valuation exercises, it is necessary to better understand the likely consequences of human actions on ecosystems, the impacts of ecosystem change on ecosystem services and biodiversity, the value of these impacts on human welfare, and the impacts and values to incentives. It is necessary to properly embed the distributional objectives into the objective function of the policy maker. Finally, and most importantly, it is necessary to properly assess the role of the local communities in the management of the resource and the role of the resource in income generation at both the community and the national levels. Once values are estimated, it is necessary to map the distribution of the ecosystem benefits and the beneficiaries of biodiversity changes – who wins and who loses? This leads to a stakeholder analysis at different spatial scales, which in the regional context of the LAC is particularly important. Both localised community studies and regional eco-region studies are essential.
Certainly such a service to the economy can be valued in monetary terms, and it is to this kind of research that we must turn in order to facilitate further conservation efforts of these resources. However, for a true picture of the environmental resources upon which this service depends, it is necessary to also identify the other provisioning, regulating and cultural services of the resource. In this way, human welfare impacts can be more truly judged, and effective resource management can be undertaken.

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Notes

1 Only the flatback (Natator depressa) is not found in the LAC, this species is endemic to Australia.

2 Paran and Williams (2007) provide a thought-provoking discussion on the validity of even the categorisation of countries into “developed” and “developing”, given that most countries in the world face problems with “development”.

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Table des illustrations

Titre Figure 1. Sea Turtle Nesting in the Caribbean
Crédits Source: Dow et al., 2007
URL http://etudescaribeennes.revues.org/docannexe/image/10990/img-1.jpg
Fichier image/jpeg, 52k
Titre Figure 3. The Process of Environmental Valuation
URL http://etudescaribeennes.revues.org/docannexe/image/10990/img-2.jpg
Fichier image/jpeg, 29k
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Pour citer cet article

Référence électronique

Sonja S. Teelucksingh, Scott Eckert et Paulo A.L.D. Nunes, « Marine Turtles, Ecosystem Services and Human Welfare in the Marine Ecosystems of the Caribbean Sea: A Discussion of Key Methodologies », Études caribéennes [En ligne], 15 | Avril 2010, mis en ligne le 15 avril 2010, consulté le 20 octobre 2017. URL : http://etudescaribeennes.revues.org/10990 ; DOI : 10.4000/etudescaribeennes.10990

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Auteurs

Sonja S. Teelucksingh

Department of Economics, University of the West Indies, Trinidad, Sir Arthur Lewis Institute of Social and Economic Studies (SALISES),University of the West Indies, Trinidad, Fondazione Eni Enrico Mattei, Italy; sonja.teelucksingh@sta.uwi.edu

Scott Eckert

Wider Caribbean Sea Turtle Conservation Network, WIDECAST

Paulo A.L.D. Nunes

Fondazione Eni Enrico Mattei, Italy, Department of Economics, Ca’ Foscari University of Venice, Italy

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Droits d’auteur

Licence Creative Commons
Les contenus d’Études caribéennes sont mis à disposition selon les termes de la Licence Creative Commons Attribution - Pas d'Utilisation Commerciale 4.0 International.

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