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- Perceived social benefits and drawbacks of sea turtle conservation efforts in a globally important sea turtle rookeryPublication . Vieira, Sara; Jiménez, Victor; Ferreira-Airaud, Betania; Pina, Antunes; Soares, Venceslau; Tiwari, Manjula; Teodosio, Maria; Castilho, Rita; Nuno, AnaConservation interventions have wide-ranging social impacts - both positive and negative. Yet a limited understanding of how conservation initiatives affect people's livelihoods often hinders our ability to learn from past efforts and design more effective and equitable conservation measures. This is particularly needed when there is a high degree of overlap between critical habitats and human activities or a high cultural and economic demand for products derived from the conservation target. Here, we explore the social impacts of sea turtle conservation initiatives implemented on Sao Tome Island (Gulf of Guinea) as a case study and consider how these might enhance or hinder future efforts. Semi-structured interviews were conducted with key actors involved in the sea turtle trade in December 2014-February 2015 (prior to the implementation of key initiatives) and February-April 2022. Our findings suggest a clear reduction in the scale of the sea turtle trade and the number of main actors involved. However, most respondents previously involved in the trade had experienced economic displacement and several associated social impacts, such as the reduced ability to support family and friends and food insecurity, due to trade restrictions. Financial capital was the main barrier to transitioning to alternative livelihoods, followed by the lack of skills and peer pressure. Finally, this study highlights the importance of considering human dimensions during the planning and implementation phase of conservation actions and the need for more investment focused on the well-being of communities to ensure the long-term survival of endangered species.
- Green and hawksbill sea turtles of Eastern Atlantic: new insights into a globally important rookery in the Gulf of GuineaPublication . Ferreira-Airaud, Betania; Vieira, Sara; Branco, Maria; Pina, Antunes; Soares, Venceslau; Tiwari, Manjula; Witt, Matthew; Castilho, Rita; Teodosio, Maria; Hawkes, Lucy A.Sea turtles are critical components of marine ecosystems, and their conservation is important for Ocean Governance and Global Planet Health. However, there is limited knowledge of their ecology in the Gulf of Guinea. To fill this knowledge gap, this study presents the first integrative assessment of green and hawksbill turtles in the region, combining nesting surveys over 9 years and telemetry data, to offer insights into these population dynamics, and behaviours, including nesting preferences, morphological and reproductive parameters, diving patterns and inter-nesting core-use areas. Both green and hawksbill turtles are likely making a recovery on Sao Tome, potentially driven by sustained conservation efforts. There are preliminary indications of recovery, but we interpret this cautiously. Coupled with satellite tracking, this study estimated that 482 to 736 green turtles and 135 to 217 hawksbills nest on the beaches of Sao Tome. Their movements overlap significantly with a proposed Marine Protected Area (MPA), which suggests they may be well placed for conservation if managed appropriately. However, the presence of artisanal fisheries and emerging threats, such as sand mining and unregulated tourism, highlight the urgent need for robust management strategies that align global conservation objectives with local socioeconomic realities. This study significantly enhances our understanding of the ecology and conservation needs of the green and hawksbill turtles in the Gulf of Guinea. The insights gleaned here can contribute to the development of tailored conservation strategies that benefit these populations and the ecosystem services upon which they depend. This study presents a comprehensive assessment of green and hawksbill sea turtles in the Gulf of Guinea, combining 9 years of nesting area surveys with telemetry data. Our findings reveal promising signs of recovery for green and hawksbill turtles, driven by conservation efforts. Our research underscores the importance of effective conservation strategies, especially in the face of emerging threats, to protect these vital marine species and their ecosystems in the Eastern Atlantic.image
- Metal accumulation in female green sea turtles (Chelonia mydas) from Eastern Atlantic affects their egg quality with potential implications for embryonic developmentPublication . Morão, Inês F.C.; Simões, Tiago; Casado, Roger B.; Vieira, Sara; Ferreira-Airaud, Betânia; Caliani, Ilaria; Noi, Agata Di; Casini, Silvia; Fossi, Maria C.; Lemos, Marco F.L.; Novais, Sara C.Sea turtles, with their global distribution and complex life cycle, often accumulate pollutants such as metals and metalloids due to their extended lifespan and feeding habits. However, there are limited studies exploring the impact of metal pollution on the reproductive health of female sea turtles, specifically focusing on the quality of their eggs, which has significant implications for the future generations of these charismatic animals. Sao Tome Island, a crucial nesting and feeding habitat for green sea turtles, underscores the urgent need for comprehensive research in this ecologically significant area. This study aimed to investigate whether metals and metalloids in the blood of nesting female green sea turtles induce genotoxic effects in their erythrocytes and affect their egg morphometric characteristics and the composition of related compartments. Additionally, this study aimed to evaluate whether the quality of energetic reserves for embryo development (fatty acids in yolk's polar and neutral lipids) is influenced by the contamination status of their predecessors. Results revealed correlations between Cu and Hg levels and increased "lobed" erythrocytes, while As and Cu negatively influenced shell thickness. In terms of energy reserves, both polar and neutral lipid fractions contained primarily saturated and monounsaturated fatty acids, with prevalent 18:1n-9, 18:0, 16:0, 14:0, and 12:0 fatty acids in yolk samples. The yolk polar fraction was more susceptible to contaminant levels in female sea turtles, showing consistent negative correlations between pollution load index and essential n3 fatty acids, including linolenic, eicosatrienoic, eicosapentaenoic, and docosapentaenoic acids, crucial for embryonic development. These metals accumulation, coupled with the reduced availability of these key fatty acids, may disrupt the eicosanoid and other important pathways, affecting reproductive development. This study reveals a negative correlation between metal contamination in female sea turtles' blood and egg lipid reserves, raising concerns about embryonic development and the species' future generations.
- Green and Hawksbill sea turtles of Eastern Atlantic: new insights into a globally important rookery in the Gulf of GuineaPublication . Ferreira-Airaud, Betânia; Vieira, Sara; Branco, Maria; Pina, Antunes; Soares, Venceslau; Tiwari, Manjula; Witt, Matthew; Castilho, Rita; Teodosio, Maria; Hawkes, Lucy A.Sea turtles are critical components of marine ecosystems, and their conservation is important for Ocean Governance and Global Planet Health. However, there is limited knowledge of their ecology in the Gulf of Guinea. To fill this knowledge gap, this study presents the first integrative assessment of green and hawksbill turtles in the region, combining nesting surveys over 9 years and telemetry data, to offer insights into these population dynamics, and behaviours, including nesting preferences, morphological and reproductive parameters, diving patterns and inter-nesting core-use areas. Both green and hawksbill turtles are likely making a recovery on São Tomé, potentially driven by sustained conservation efforts. There are preliminary indications of recovery, but we interpret this cautiously. Coupled with satellite tracking, this study estimated that 482 to 736 green turtles and 135 to 217 hawksbills nest on the beaches of São Tomé. Their movements overlap significantly with a proposed Marine Protected Area (MPA), which suggests they may be well placed for conservation if managed appropriately. However, the presence of artisanal fisheries and emerging threats, such as sand mining and unregulated tourism, highlight the urgent need for robust management strategies that align global conservation objectives with local socioeconomic realities. This study significantly enhances our understanding of the ecology and conservation needs of the green and hawksbill turtles in the Gulf of Guinea. The insights gleaned here can contribute to the development of tailored conservation strategies that benefit these populations and the ecosystem services upon which they depend.
- Correlation between trace element concentrations in the blood of female hawksbill (Eretmochelys imbricata) and egg quality in nesting populations of São Tomé IslandPublication . Morão, Inês F. C.; Simões, Tiago; Casado, Roger B.; Vieira, Sara; Ferreira-Airaud, Betânia; Caliani, Ilaria; Noi, Agata Di; Casini, Silvia; Fossi, Maria C.; Lemos, Marco F. L.; Novais, Sara C.Metals and metalloids can pose a significant threat to sea turtles, as these contaminants tend to accumulate in their bodies over time, due to their long lifespans and varied feeding habits. S˜ ao Tom´e and Príncipe’s archipelago hosts the last remaining rookery for hawksbill sea turtles (Eretmochelys imbricata) in the region. The study aimed to determine the levels of metals and metalloids accumulated by this population and to investigate their possible genotoxicity in nesting females’ blood as well as potential effects on their eggs in terms of morphometric characteristics and the quality of their lipidic reserves, essential for embryo development. Higher levels of Hg were found to be correlated with increased “lobed-shaped nuclei” in erythrocytic count, suggesting genotoxicity effects in this population. Higher levels of Se were correlated with thicker and heavier eggshells, while Pb levels were associated with the reduction of the egg’s diameter. Metal contamination in females’ blood significantly affected yolk polar fatty acids. Significant negative correlations were found between general metal contamination (PLI) and saturated fatty acids (SFA), while positive correlations were observed for essential omega-6 fatty acids (n6), mostly influenced by Cu, Fe, and Hg concentrations. This suggests that these omega-6 fatty acids are being synthesized from SFA, potentially indicating stress response by metal exposure. The present results point to some potential alterations in the normal embryonic development of these turtle eggs, influenced by metal contamination, which should raise some concerns about the future of this critically endangered species and call for additional conservation efforts in the region.
- Discriminative influence of persistent organic pollutants on nesting green sea turtles through genotoxicity, oxidative stress and reproductive related markersPublication . Morão, Inês F. C.; Muñoz-Arnanz, Juan; Simões, Tiago; Bartalini, Alice; Vieira, Sara; Ferreira-Airaud, Betânia; Caliani, Ilaria; Noi, Agata Di; Casini, Silvia; Fossi, Maria Cristina; Jiménez, Begoña; Lemos, Marco F. L.; Novais, Sara C.Persistent organic pollutants (POPs) including polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organochloride pesticides (OCPs) affect biodiversity by bioaccumulating through food webs, impacting marine organisms like endangered sea turtles. This study represents the first evaluation of these contaminants in sea turtles nesting in São Tomé and Príncipe. The main goal was to evaluate PCBs, PBDEs and OCPs levels in sea turtles’ blood and investigate their potential effects on erythrocytic nuclear abnormalities (ENAs) and oxidative stress and reproduction-related gene expression. The relative mean abundance for contaminants was ΣPCBs > ΣOCPs > ΣPBDEs. Contaminants such as PCB-28, PCB-138, PCB-153, PCB-180 and p,p’- DDE were associated with ENAs, suggesting potential genetic instability and cellular disruption. PCB-126, PBDE100, and o,p’-DDD correlated with antioxidant and detoxification genes (glrx3, gst, txnip, txnrd2, and gclc), suggesting oxidative stress responses. The reproduction-related gene est17 was correlated with α- and β-HCH, potentially affecting ovary development. Correlations between ace2 and various PCBs, PBDEs, and o,p′-DDD suggest disruptions in follicular development and egg transport. Embryo development genes (hoxA1 and tuba1) were associated with PBDE-154, PBDE-100 and o,p’-DDD, suggesting possible embryonic alterations. These findings highlight the impacts of POPs on nesting female green turtles in São Tomé, threatening this endangered population.