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1.
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
2.
Conserv Biol ; 33(6): 1380-1391, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30950112

RESUMO

Understanding threats acting on marine organisms and their conservation status is vital but challenging given a paucity of data. We studied the cumulative human impact (CHI) on and conservation status of seahorses (Hippocampus spp.)-a genus of rare and data-poor marine fishes. With expert knowledge and relevant spatial data sets, we built linear-additive models to assess and map the CHI of 12 anthropogenic stressors on 42 seahorse species. We examined the utility of indices of estimated impact (impact of each stressor and CHI) in predicting conservation status for species with random forest (RF) models. The CHI values for threatened species were significantly higher than those for nonthreatened species (category based on International Union for Conservation of Nature Red List). We derived high-accuracy RF models (87% and 96%) that predicted that 5 of the 17 data-deficient species were threatened. Demersal fishing practices with high bycatch and pollution were the best predictors of threat category. Major threat epicenters were in China, Southeast Asia, and Europe. Our results and maps of CHI may help guide global seahorse conservation and indicate that modeling and mapping human impacts can reveal threat patterns and conservation status for data-poor species. We found that for exploring threat patterns of focal species, species-level CHI models are better than existing ecosystem-level CHI models.


Uso de Modelos de Impacto Humano Acumulativo para Revelar los Patrones de Amenaza Mundial para Hipocampos Resumen El entendimiento de las amenazas que actúan sobre los organismos marinos y su estado de conservación es de suma importancia pero a la vez un gran reto debido a la insuficiencia de datos. Estudiamos el estado de conservación y el impacto humano acumulativo (CHI, en inglés) que existe sobre los hipocampos (Hippocampus spp.)- un género de peces marinos raro y escaso de datos. Construimos modelos lineales aditivos con el conocimiento de expertos y conjuntos de datos espaciales relevantes para evaluar y mapear el CHI de los doce estresantes antropogénicos que afectan a las 42 especies de hipocampos. Examinamos la utilidad que tienen los índices de impacto estimado (el impacto de cada estresante y cada CHI) para la predicción del estado de conservación de las especies usando modelos de bosque azaroso (RF, en inglés). Los valores del CHI para las especies amenazadas fueron considerablemente más altos que aquellos obtenidos para las especies no amenazadas (categoría basada en la Lista Roja de la Unión Internacional para la Conservación de la Naturaleza). De esto derivamos modelos RF de alta certeza (87% y 96%), los cuales pronosticaron que cinco de las 17 especies deficientes de datos estaban amenazadas. Las prácticas de pesca demersal con una captura accesoria elevada y la contaminación fueron los mejores pronosticadores de la categoría de amenaza. Los principales epicentros de amenaza se ubicaron en China, el sureste asiático y en Europa. Nuestros resultados y mapas de CHI pueden ayudar a guiar la conservación mundial de hipocampos y también indican que el modelado y el mapeo de de los impactos humanos pueden revelar los patrones de amenaza y el estado de conservación de las especies deficientes de datos. Descubrimos que para explorar los patrones de amenaza de especies focales, son mejores los modelos de CHI a nivel de especie que los ya existentes modelos de CHI a nivel de ecosistema.


Assuntos
Ecossistema , Smegmamorpha , Animais , China , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Europa (Continente) , Humanos
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.
Conserv Biol ; 23(4): 899-910, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19627319

RESUMO

We compared and integrated marine protected areas proposed through community and scientific assessments in 2 regions of British Columbia, Canada. The community priorities were identified during individual and group interviews with knowledgeable resource users. The scientific priorities were developed with abiotic and biotic data in Marxan, a decision-support tool. The resulting maps of community-based and science-based priorities were very similar for the inshore areas, which lent credibility to both approaches. The resource users thought the science-based maps were fairly good at highlighting areas important for conservation, but preferred the scenarios that integrated the 2 maps to either constituent map. Incorporating spatial variation in human impacts on the marine areas and commercial fishing, which are both costs of protection, into our Marxan analyses led to scenarios that were different from either constituent map. Our results show the value of integrating community-based and science-based approaches in conservation planning to achieve community acceptance and conservation utility. They also reveal that people's assessments on the basis of their traditional ecological knowledge may serve as a reasonable proxy for scientific approaches in selecting areas of ecological value.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biologia Marinha , Colúmbia Britânica
5.
Conserv Biol ; 22(5): 1225-32, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18680503

RESUMO

Achieving multiple conservation objectives can be challenging, particularly under high uncertainty. Having agreed to limit seahorse (Hippocampus) exports to sustainable levels, signatories to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) were offered the option of a single 10-cm minimum size limit (MSL) as an interim management measure for all Hippocampus species (> or =34). Although diverse stakeholders supported the recommended MSL, its biological and socioeconomic implications were not assessed quantitatively. We combined population viability analysis, model sensitivity analysis, and economic information to evaluate the trade-off between conservation threat to and long-term cumulative income from these exploited marine fishes of high conservation concern. We used the European long-snouted seahorse (Hippocampus guttulatus) as a representative species to compare the performance of MSLs set at alternative biological reference points. Our sensitivity analyses showed that in most of our scenarios, setting the MSL just above size at maturity (9.7 cm in H. guttulatus) would not prevent exploited populations from becoming listed as vulnerable. By contrast, the relative risk of decline and extinction were almost halved--at a cost of only a 5.6% reduction in long-term catches--by increasing the MSL to the size reached after at least one full reproductive season. On the basis of our analysis, a precautionary increase in the MSL could be compatible with sustaining fishers' livelihoods and international trade. Such management tactics that aid species conservation and have minimal effects on long term catch trends may help bolster the case for CITES trade management of other valuable marine fishes.


Assuntos
Comércio/legislação & jurisprudência , Conservação dos Recursos Naturais/métodos , Modelos Teóricos , Smegmamorpha/fisiologia , Animais , Tamanho Corporal , Simulação por Computador , Conservação dos Recursos Naturais/legislação & jurisprudência , Oceanos e Mares , Dinâmica Populacional , Análise de Regressão , Fatores Socioeconômicos
6.
PLoS One ; 13(3): e0190232, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29538370

RESUMO

Locally sustainable resource extraction activities, at times, transform into ecologically detrimental enterprises. Understanding such transitions is a primary challenge for conservation and management of many ecosystems. In marine systems, over-exploitation of small-scale fisheries creates problems such as reduced biodiversity and lower catches. However, long-term documentation of how governance and associated changes in fishing gears may have contributed to such declines is often lacking. Using fisher interviews, we characterized fishing gear dynamics over 60 years (1950-2010) in a coral reef ecosystem in the Philippines subject to changing fishing regulations. In aggregate fishers greatly diversified their use of fishing gears. However, most individual fishers used one or two gears at a time (mean number of fishing gears < 2 in all years). Individual fishing effort (days per year) was fairly steady over the study period, but cumulative fishing effort by all fishers increased 240%. In particular, we document large increases in total effort by fishers using nets and diving. Other fishing gears experienced less pronounced changes in total effort over time. Fishing intensified through escalating use of non-selective, active, and destructive fishing gears. We also found that policies promoting higher production over sustainability influenced the use of fishing gears, with changes in gear use persisting decades after those same policies were stopped. Our quantitative evidence shows dynamic changes in fishing gear use over time and indicates that gears used in contemporary small-scale fisheries impact oceans more than those used in earlier decades.


Assuntos
Pesqueiros/tendências , Conservação dos Recursos Naturais/legislação & jurisprudência , Conservação dos Recursos Naturais/tendências , Recifes de Corais , Crime , Política Ambiental , Pesqueiros/legislação & jurisprudência , História do Século XX , História do Século XXI , Humanos , Entrevistas como Assunto , Filipinas
7.
Ambio ; 35(2): 57-64, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16722250

RESUMO

Collecting marine organisms for the discovery and development of pharmaceuticals has been perceived variously as sustaining and threatening conservation. Our initial expectations that marine bioprospecting might pose conservation challenges were largely not confirmed. Thousands of marine species have been collected for initial assessment, but usually only in very small amounts. Very few compounds are sufficiently promising to provoke re-collections, where volumes can be much larger. This is where conservation concerns may arise, particularly if the organism is rare, has a restricted distribution, or is targeted in one narrow area. However, industry generally seeks to avoid dependency on small populations, for economic as well as ecological reasons. Alternative supply strategies to wild capture include synthesis and culture. Mandatory collection protocols and environmental impact (stock) assessments are useful routes for management to achieve sustainable use where extraction is desirable. In general, the scanty information available suggests that marine bioprospecting for pharmaceuticals may have minimal impacts on the environment, particularly compared with those created by other pressures.


Assuntos
Biologia Marinha , Preparações Farmacêuticas , Animais , Produtos Biológicos , Conservação dos Recursos Naturais , Plantas , Especificidade da Espécie
8.
Evolution ; 57(6): 1374-86, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12894945

RESUMO

Modern theory predicts that relative parental investment of the sexes in their young is a key factor responsible for sexual selection. Seahorses and pipefishes (family Syngnathidae) are extraordinary among fishes in their remarkable adaptations for paternal care and frequent occurrences of sex-role reversals (i.e., female-female competition for mates), offering exceptional opportunities to test predictions of sexual selection theory. During mating, the female transfers eggs into or onto specialized egg-brooding structures that are located on either the male's abdomen or its tail, where they are osmoregulated, aerated, and nourished by specially adapted structures. All syngnathid males exhibit this form of parental care but the brooding structures vary, ranging from the simple ventral gluing areas of some pipefishes to the completely enclosed pouches found in seahorses. We present a molecular phylogeny that indicates that the diversification of pouch types is positively correlated with the major evolutionary radiation of the group, suggesting that this extreme development and diversification of paternal care may have been an important evolutionary innovation of the Syngnathidae. Based on recent studies that show that the complexity of brooding structures reflects the degree of paternal investment in several syngnathid species, we predicted sex-role reversals to be more common among species with more complex brooding structures. In contrast to this prediction, however, both parsimony- and likelihood-based reconstructions of the evolution of sex-role reversal in pipefishes and seahorses suggest multiple shifts in sex roles in the group, independent from the degree of brood pouch development. At the same time, our data demonstrate that sex-role reversal is positively associated with polygamous mating patterns, whereas most nonreversed species mate monogamously, suggesting that selection for polygamy or monogamy in pipefishes and seahorses may strongly influence sex roles in the wild.


Assuntos
Comportamento Paterno , Filogenia , Seleção Genética , Comportamento Sexual Animal , Smegmamorpha/genética , Smegmamorpha/fisiologia , Animais , Sequência de Bases , DNA Mitocondrial/genética , Funções Verossimilhança , Dados de Sequência Molecular , Análise de Sequência de DNA , Smegmamorpha/anatomia & histologia
10.
PLoS One ; 4(7): e6258, 2009 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-19623248

RESUMO

BACKGROUND: Marine populations have been declining at a worrying rate, due in large part to fishing pressures. The challenge is to secure a future for marine life while minimizing impacts on fishers and fishing communities. METHODS AND PRINCIPAL FINDINGS: Rather than selecting areas where fishing is banned -- as is usually the case with spatial management -- we assess the concept of designating areas where fishing is permitted. We use spatial catch statistics for thirteen commercial fisheries on Canada's west coast to determine the minimum area that would be needed to maintain a pre-ascribed target percentage of current catches. We found that small reductions in fisheries yields, if strategically allocated, could result in large unfished areas that are representative of biophysical regions and habitat types, and have the potential to achieve remarkable conservation gains. CONCLUSIONS: Our approach of selecting fishing areas instead of reserves could help redirect debate about the relative values that society places on conservation and extraction, in a framework that could gain much by losing little. Our ideas are intended to promote discussions about the current status quo in fisheries management, rather than providing a definitive solution.


Assuntos
Conservação dos Recursos Naturais , Pesqueiros , Peixes , Biologia Marinha , Animais , Colúmbia Britânica
11.
Mol Phylogenet Evol ; 30(2): 261-72, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14715219

RESUMO

Phylogenetic relationships among 93 specimens of 22 species of seahorses (genus Hippocampus) from the Atlantic and Indo-Pacific Oceans were analysed using cytochrome b gene sequence data. A maximum sequence divergence of 23.2% (Kimura 2-parameter model) suggests a pre-Tethyan origin for the genus. Despite a greater number of seahorse species in the Indo-Pacific than in the Atlantic Ocean, there was no compelling genetic evidence to support an Indo-Pacific origin for the genus Hippocampus. The phylogenetic data suggest that high diversity in the Indo-Pacific results from speciation events dating from the Pleistocene to the Miocene, or earlier. Both vicariance and dispersal events in structuring the current global distribution of seahorses. The results suggested that several species designations need re-evaluating, and further phylogeographic studies are required to determine patterns and processes of seahorse dispersal.


Assuntos
Citocromos b/genética , DNA Mitocondrial , Animais , DNA/química , Marcadores Genéticos , Filogenia , Smegmamorpha , Software , Especificidade da Espécie
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