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1.
J Fish Biol ; 104(5): 1548-1565, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38408838

RESUMO

Marine community science presents an important route to gather valuable scientific information while also influencing local management and policy, thus contributing to marine conservation efforts. Because seahorses are cryptic but charismatic species, they are good candidates for engaging diverse people to help overcome the many gaps in biological knowledge. We have synthesized information contributed to the community science project iSeahorse from October 2013 to April 2022 for 35 of 46 known seahorse species. We then compared the obtained results with information in existing IUCN Red List assessments, executed from 2014 to 2017, to explore the potential of iSeahorse in expanding seahorse knowledge. Our results show updated geographic ranges for 7 seahorse species, new habitats described for 24 species, observations outside the previously recorded depth range for 14 species, and new information on sex ratio for 15 species and on pregnancy seasonality for 11 species. As one example of the power of iSeahorse, contributed observations on Coleman's pygmy seahorse (Hippocampus colemani) indicated that its geographic range is thousands of square kilometers larger, its habitat more diverse, and its depth range shallower than previously known. It is clear that iSeahorse is expanding knowledge on seahorses to a level that will help improve IUCN Red List assessments. The power of community science for marine conservation in general needs to be fully explored.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Smegmamorpha , Animais , Feminino , Masculino , Razão de Masculinidade , Espécies em Perigo de Extinção
2.
Conserv Biol ; 34(3): 644-653, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31840860

RESUMO

What happens when those who provide conservation advice are required to take policy and management action based on that advice? Conservation advocates and scientists often try to prompt regulatory change that has significant implications for government without facing the challenge of managing such change. Through a case study, we placed ourselves in the role of the government of Thailand, facing obligations to seahorses (Hippocampus spp.) under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). These obligations include ensuring that its exports of seahorses do not damage wild populations. We applied a CITES-approved framework (which we developed) to evaluate the risks of such exports to 2 seahorse species. We used the framework to evaluate the pressures that put wild populations of the species at risk; whether current management mitigates the risk or offsets these pressures; and whether the species is responding as hoped to management policy. We based our analysis on information in published and grey literature, local knowledge, citizen science data, results of government research, and expert opinion. To meet CITES obligations, exports of both species would need to be prohibited until more precautionary adaptive management emerged. The risk of any exports of Hippocampus trimaculatus was above a tolerable level because of a lack of appropriate management to mitigate risks. In contrast, the risk of any exports of Hippocampus kuda could become tolerable if monitoring were put in place to assess the species' response to management. The process we developed for Authorities to determine risk in response to CITES guidelines was challenging to implement even without the need for government to consider social implications of conservation action. Despite the imperfections of our risk evaluation, however, it still served to support adaptive management. Conservationists need to keep implementation in mind when offering advice.


Realidades al Ofrecerle Consejos sobre CITES a los Gobiernos Resumen ¿Qué ocurre cuando se requiere que quienes proporcionan consejos para la conservación realicen acciones políticas y de manejo basadas en aquellos consejos? Los científicos y partidarios de la conservación tratan con frecuencia de provocar cambios legislativos que tienen implicaciones significativas para el gobierno sin enfrentar el reto que implica manejar ese cambio. Mediante un estudio de caso, nos colocamos en el papel del gobierno de Tailandia, el cual enfrenta obligaciones con los caballitos de mar (Hippocampus spp.) bajo la Convención sobre el Comercio Internacional de Especies Amenazadas de Flora y Fauna Silvestre (CITES). Estas obligaciones incluyen asegurar que las exportaciones de caballitos de mar no causen daño a las poblaciones silvestres de este grupo. Aplicamos un marco de trabajo aprobado por CITES (el cual desarrollamos) para evaluar los riesgos de dichas exportaciones para dos especies de hipocampos. Usamos el marco de trabajo para valorar las presiones que ponen a las poblaciones silvestres de ambas especies en riesgo; si el manejo actual mitiga o compensa el riesgo de estas presiones; y si las especies están respondiendo como se esperaba a las políticas de manejo. Basamos nuestro análisis en información tomada de literatura publicada y de la literatura gris, del conocimiento local, los datos de la ciencia ciudadana, los resultados de investigaciones realizadas por el gobierno y de la opinión de expertos. Para cumplir con las obligaciones de CITES, las exportaciones de ambas especies necesitarían estar prohibidas hasta que existiera un manejo adaptativo más preventivo. El riesgo de cualquier exportación de H. trimaculatus quedó por encima de un nivel tolerable debido a la falta de un manejo apropiado para mitigar los riesgos. Como contraste, el riesgo de cualquier exportación de H. kuda podría volverse tolerable si se realizaran monitoreos para evaluar la respuesta de la especie al manejo. Fue todo un reto implementar el proceso que desarrollamos para que las autoridades determinen el riesgo siguiendo la pauta de CITES incluso sin la necesidad de que el gobierno considerara las implicaciones sociales de la acción de conservación. Sin embargo, a pesar de las imperfecciones de nuestra evaluación de riesgo, todavía funcionó como apoyo para el manejo adaptativo. Los conservacionistas necesitan seguir considerando la implementación cuando ofrecen consejos.


Assuntos
Comércio , Conservação dos Recursos Naturais , Animais , Governo , Internacionalidade , Tailândia
3.
J Fish Biol ; 93(4): 649-663, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29971766

RESUMO

Analysing the associations between the endangered White's seahorse Hippocampus whitei and characteristics of its environment (including habitat, prey and predator variables) in an estuary in New South Wales, Australia, revealed that seahorses had a greater number of significant associations with environmental correlates within a single seagrass bed than among seagrass beds. Predator abundance was negatively correlated with H. whitei abundances among seven seagrass beds (200-6,000 m apart) and no ecological correlate was associated with H. whitei body size distributions. Within the seagrass bed with the greatest number of H. whitei, individuals preferentially selected locations that were deeper, had denser seagrass, more epiphytic prey types and fewer predators. Smaller H. whitei were associated with greater depths within the bed. In this study, each class of ecological correlate (habitat, prey, predators) was found to have at least one significant relationship with H. whitei, depending on the scale, demonstrating that all three are important to H. whitei populations. As such, future studies that evaluate animal populations may benefit from holistic approaches that consider each of these together. For animals that are experiencing dramatic population declines due to habitat destruction, as H. whitei has over the last decade, a better understanding of its relationship to its environment is important to inform conservation action.


Assuntos
Ecossistema , Smegmamorpha/fisiologia , Animais , Austrália , Tamanho Corporal , Estuários , New South Wales , Densidade Demográfica , Smegmamorpha/anatomia & histologia
4.
Cerebrovasc Dis ; 29(6): 592-6, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20389068

RESUMO

BACKGROUND: For MR perfusion-diffusion mismatch to be clinically useful as a means of selecting patients for thrombolysis, it needs to occur in real time at the MRI console. Visual mismatch assessment has been used clinically and in trials but has not been systematically validated. We compared the accuracy of visually rating console-generated images with offline volumetric measurements using data from the Echoplanar Imaging Thrombolytic Evaluation Trial (EPITHET). METHODS: Perfusion time-to-peak (TTP) and diffusion-weighted images (DWI) (as generated by commercial MRI console software) and T(max) perfusion maps (which required offline calculation) were visually rated. Perfusion-diffusion mismatch, defined as a ratio of perfusion:diffusion lesion volume of >1.2, was independently scored by 1 expert and 2 inexperienced raters blinded to calculated volumes and clinical information. Visual mismatch was compared with region-of-interest-based volumetric calculation, which was used as the gold standard. RESULTS: Volumetric calculation demonstrated perfusion-diffusion mismatch in 85/99 patients. Visual TTP-DWI mismatch was correctly classified by the experienced rater in 82% of the cases (sensitivity: 0.86; specificity: 0.54) compared to 73% for the inexperienced raters (sensitivity: 0.75; specificity: 0.57). The interrater reliability for TTP-DWI mismatch was moderate (kappa = 0.50). Visual T(max)-DWI mismatch performed better (agreement - 93 and 87%, sensitivity - 95 and 88%, specificity - 77 and 82% for the experienced and inexperienced raters, respectively). CONCLUSIONS: The assessment of visual TTP-DWI mismatch at the MRI console is insufficiently reliable for use in clinical trials. Differences in perfusion analysis technique and visual inaccuracies combine to make visual TTP-DWI mismatch substantially different to volumetric T(max)-DWI mismatch. Automated software that applies perfusion thresholds may improve the reproducibility of real-time mismatch assessment.


Assuntos
Circulação Cerebrovascular/fisiologia , Imagem de Difusão por Ressonância Magnética , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/patologia , Terapia Trombolítica/métodos , Encéfalo/patologia , Método Duplo-Cego , Humanos , Interpretação de Imagem Assistida por Computador , Variações Dependentes do Observador , Seleção de Pacientes , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X
5.
Zootaxa ; 4146(1): 1-66, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27515600

RESUMO

Nomenclatural clarity is vital for the collection, dissemination, and retrieval of natural history information, which itself is necessary for effective conservation and management of species. Seahorses (genus Hippocampus) are small marine fishes that in many cases are heavily exploited and suffering severe population declines worldwide, leading to conservation concern and action. Here we provide a brief history of seahorse taxonomy, and attempt to clarify seahorse nomenclature by reducing redundancy and exposing areas of disagreement in need of further study. We provide an annotated list of the 41 species we currently recognize as valid, and describe their geographical distributions to offer a solid foundation for future research and conservation efforts. We base our conclusions on available morphological, genetic and distributional data, re-examination of the relevant literature, previous examination of almost all original type specimens, familiarity with many thousands of other live and dead specimens, and photographs of seahorses. This work should lead to greater taxonomic clarity by highlighting known research gaps and by ensuring that each species designation is justified by robust and defensible taxonomic protocols. Such clarity should facilitate greater efficacy in management and conservation.


Assuntos
Peixes/classificação , Distribuição Animal , Animais , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Feminino , Peixes/anatomia & histologia , Masculino , Filogeografia , Especificidade da Espécie
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