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1.
PLoS One ; 12(12): e0190021, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29284017

RESUMO

Fisheries bycatch is a widespread and serious issue that leads to declines of many important and threatened marine species. However, documenting the distribution, abundance, population trends and threats to sparse populations of marine species is often beyond the capacity of developing countries because such work is complex, time consuming and often extremely expensive. We have developed a flexible tool to document spatial distribution and population trends for dugongs and other marine species in the form of an interview questionnaire supported by a structured data upload sheet and a comprehensive project manual. Recognising the effort invested in getting interviewers to remote locations, the questionnaire is comprehensive, but low cost. The questionnaire has already been deployed in 18 countries across the Indo-Pacific region. Project teams spent an average of USD 5,000 per country and obtained large data sets on dugong distribution, trends, catch and bycatch, and threat overlaps. Findings indicated that >50% of respondents had never seen dugongs and that 20% had seen a single dugong in their lifetimes despite living and fishing in areas of known or suspected dugong habitat, suggesting that dugongs occurred in low numbers. Only 3% of respondents had seen mother and calf pairs, indicative of low reproductive output. Dugong hunting was still common in several countries. Gillnets and hook and line were the most common fishing gears, with the greatest mortality caused by gillnets. The questionnaire has also been used to study manatees in the Caribbean, coastal cetaceans along the eastern Gulf of Thailand and western Peninsular Malaysia, and river dolphins in Peru. This questionnaire is a powerful tool for studying distribution and relative abundance for marine species and fishery pressures, and determining potential conservation hotspot areas. We provide the questionnaire and supporting documents for open-access use by the scientific and conservation communities.


Assuntos
Documentação , Espécies em Perigo de Extinção , Pesqueiros , Animais , Especificidade da Espécie , Inquéritos e Questionários
2.
Proc Natl Acad Sci U S A ; 107(43): 18278-85, 2010 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-20176947

RESUMO

The Great Barrier Reef (GBR) provides a globally significant demonstration of the effectiveness of large-scale networks of marine reserves in contributing to integrated, adaptive management. Comprehensive review of available evidence shows major, rapid benefits of no-take areas for targeted fish and sharks, in both reef and nonreef habitats, with potential benefits for fisheries as well as biodiversity conservation. Large, mobile species like sharks benefit less than smaller, site-attached fish. Critically, reserves also appear to benefit overall ecosystem health and resilience: outbreaks of coral-eating, crown-of-thorns starfish appear less frequent on no-take reefs, which consequently have higher abundance of coral, the very foundation of reef ecosystems. Effective marine reserves require regular review of compliance: fish abundances in no-entry zones suggest that even no-take zones may be significantly depleted due to poaching. Spatial analyses comparing zoning with seabed biodiversity or dugong distributions illustrate significant benefits from application of best-practice conservation principles in data-poor situations. Increases in the marine reserve network in 2004 affected fishers, but preliminary economic analysis suggests considerable net benefits, in terms of protecting environmental and tourism values. Relative to the revenue generated by reef tourism, current expenditure on protection is minor. Recent implementation of an Outlook Report provides regular, formal review of environmental condition and management and links to policy responses, key aspects of adaptive management. Given the major threat posed by climate change, the expanded network of marine reserves provides a critical and cost-effective contribution to enhancing the resilience of the Great Barrier Reef.


Assuntos
Conservação dos Recursos Naturais/métodos , Biologia Marinha/organização & administração , Animais , Antozoários , Biodiversidade , Biomassa , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/legislação & jurisprudência , Análise Custo-Benefício , Dugong , Ecossistema , Pesqueiros , Peixes , Cadeia Alimentar , Humanos , Biologia Marinha/legislação & jurisprudência , Oceanos e Mares , Dinâmica Populacional , Queensland , Tubarões , Fatores Socioeconômicos , Tartarugas
3.
Conserv Biol ; 21(2): 387-99, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17391189

RESUMO

Allocating money for species conservation on the basis of threatened species listings is not the most cost-effective way of promoting recovery or minimizing extinction rates. Using ecological and social factors in addition to threat categories, we designed a decision-support process to assist policy makers in their allocation of resources for the management of native wildlife and to clarify the considerations leading to a priority listing. Each species is scored on three criteria at the scale of the relevant jurisdiction: (1) threat category, (2) consequences of extinction, and (3) potential for successful recovery. This approach provides opportunity for independent input by policy makers and other stakeholders (who weight the relative importance of the criteria) and scientists (who score the species against the criteria). Thus the process explicitly separates societal values from the technical aspects of the decision-making process while acknowledging the legitimacy of both inputs. We applied our technique to two Australian case studies at different spatial scales: the frogs of Queensland (1,728,000 km(2); 116 species) and the mammals of the Wet Tropics bioregion (18,500 km(2); 96 species). We identified 7 frog and 10 mammal species as priorities for conservation. The frogs included 1 of the 9 species classified as endangered under Queensland legislation, 3 of the 10 species classified as vulnerable, 2 of the 22 species classified as rare, and 1 of the 75 species classified as least concern. The mammals identified included 3 of the 6 species classified as endangered, 1 of the 4 species classified as vulnerable, 5 of the 11 species classified as rare, and 1 of the 75 species classified as least concern. The methods we used to identify species were robust to comparisons across the two taxonomic groups. We concluded that (1) our process facilitates comparisons of data required to make transparent, cost-effective, and strategic management decisions across taxonomic groups and (2) the process should be used to short-list species for further discussion rather than for allocating resources per se.


Assuntos
Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/métodos , Tomada de Decisões Gerenciais , Técnicas de Apoio para a Decisão , Política Pública , Valores Sociais , Animais , Austrália , Extinção Biológica , Especificidade da Espécie
4.
J Chem Ecol ; 32(6): 1353-65, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16770723

RESUMO

Near-infrared reflectance spectroscopy was used to analyze nutrient composition of tropical and subtropical seagrasses in Queensland, Australia, as part of a broader study of impacts of grazing by dugongs on seagrass. Seagrass samples of 10 species were collected, transported to the laboratory, and separated into leaf and root/rhizome fractions. They were dried, ground, and near-infrared spectra (400-2500 nm) were collected. We used partial least-squares regression to develop calibration equations relating spectral data to standard compositional analyses performed in the laboratory. These compositional analyses focused on attributes believed to be important determinants of nutritional quality of marine vertebrate herbivores (nitrogen, organic matter, neutral detergent fiber, acid detergent fiber, lignin, neutral starch, water-soluble carbohydrates, and in vitro dry matter digestibility). Calibration equations for each attribute were developed separately for (1) roots/rhizomes and (2) leaves, irrespective of plant species. An equation that combined both plant parts was equally robust. These studies demonstrated the utility of near-infrared spectroscopy in providing rapid and cost-effective analysis of marine plants, which, in turn, permits a rigorous statistical approach to be applied to studies of foraging by marine herbivores.


Assuntos
Análise Custo-Benefício , Poaceae/química , Espectroscopia de Luz Próxima ao Infravermelho/economia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Calibragem , Análise dos Mínimos Quadrados
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