Seventy‐One Important Questions for the Conservation of Marine Biodiversity

The ocean provides food, economic activity, and cultural value for a large proportion of humanity. Our knowledge of marine ecosystems lags behind that of terrestrial ecosystems, limiting effective protection of marine resources. We describe the outcome of 2 workshops in 2011 and 2012 to establish a list of important questions, which, if answered, would substantially improve our ability to conserve and manage the world's marine resources. Participants included individuals from academia, government, and nongovernment organizations with broad experience across disciplines, marine ecosystems, and countries that vary in levels of development. Contributors from the fields of science, conservation, industry, and government submitted questions to our workshops, which we distilled into a list of priority research questions. Through this process, we identified 71 key questions. We grouped these into 8 subject categories, each pertaining to a broad component of marine conservation: fisheries, climate change, other anthropogenic threats, ecosystems, marine citizenship, policy, societal and cultural considerations, and scientific enterprise. Our questions address many issues that are specific to marine conservation, and will serve as a road map to funders and researchers to develop programs that can greatly benefit marine conservation. Setenta y Un Preguntas Importantes para la Conservación de la Biodiversidad Marina     

Sex‐Biased Inbreeding Effects on Reproductive Success and Home Range Size of the Critically Endangered Black Rhinoceros

A central premise of conservation biology is that small populations suffer reduced viability through loss of genetic diversity and inbreeding. However, there is little evidence that variation in inbreeding impacts individual reproductive success within remnant populations of threatened taxa, largely due to problems associated with obtaining comprehensive pedigree information to estimate inbreeding. In the critically endangered black rhinoceros, a species that experienced severe demographic reductions, we used model selection to identify factors associated with variation in reproductive success (number of offspring). Factors examined as predictors of reproductive success were age, home range size, number of nearby mates, reserve location, and multilocus heterozygosity (a proxy for inbreeding). Multilocus heterozygosity predicted male reproductive success (p< 0.001, explained deviance >58%) and correlated with male home range size (p < 0.01, r² > 44%). Such effects were not apparent in females, where reproductive success was determined by age (p < 0.01, explained deviance 34%) as females raise calves alone and choose between, rather than compete for, mates. This first report of a 3‐way association between an individual male's heterozygosity, reproductive output, and territory size in a large vertebrate is consistent with an asymmetry in the level of intrasexual competition and highlights the relevance of sex‐biased inbreeding for the management of many conservation‐priority species. Our results contrast with the idea that wild populations of threatened taxa may possess some inherent difference from most nonthreatened populations that necessitates the use of detailed pedigrees to study inbreeding effects. Despite substantial variance in male reproductive success, the increased fitness of more heterozygous males limits the loss of heterozygosity. Understanding how individual differences in genetic diversity mediate the outcome of intrasexual competition will be essential for effective management, particularly in enclosed populations, where individuals have restricted choice about home range location and where the reproductive impact of translocated animals will depend upon the background distribution in individual heterozygosity. Efectos de la Endogamia Sesgada por el Sexo sobre el Éxito Reproductivo y el Rango del Tamaño de Hábitat del Rinoceronte Negro, Especie en Peligro Crítico     

Assessing the Potential to Restore Historic Grazing Ecosystems with Tortoise Ecological Replacements

The extinction of large herbivores, often keystone species, can dramatically modify plant communities and impose key biotic thresholds that may prevent an ecosystem returning to its previous state and threaten native biodiversity. A potentially innovative, yet controversial, landscape‐based long‐term restoration approach is to replace missing plant‐herbivore interactions with non‐native herbivores. Aldabran giant (Aldabrachelys gigantea) and Madagascan radiated (Astrochelys radiata) tortoises, taxonomically and functionally similar to the extinct Mauritian giant tortoises (Cylindraspis spp.), were introduced to Round Island, Mauritius, in 2007 to control the non‐native plants that were threatening persistence of native species. We monitored the response of the plant community to tortoise grazing for 11 months in enclosures before the tortoises were released and, compared the cost of using tortoises as weeders with the cost of using manual labor. At the end of this period, plant biomass; vegetation height and cover; and adult, seedling, flower, and seed abundance were 3–136 times greater in adjacent control plots than in the tortoise enclosures. After their release, the free‐roaming tortoises grazed on most non‐native plants and significantly reduced vegetation cover, height, and seed production, reflecting findings from the enclosure study. The tortoises generally did not eat native species, although they consumed those native species that increased in abundance following the eradication of mammalian herbivores. Our results suggest that introduced non‐native tortoises are a more cost‐effective approach to control non‐native vegetation than manual weeding. Numerous long‐term outcomes (e.g., change in species composition and soil seed bank) are possible following tortoise releases. Monitoring and adaptive management are needed to ensure that the replacement herbivores promote the recovery of native plants. Estudiando el Potencial para Restaurar Ecosistemas Históricos de Forrajeo con Reemplazos Ecológicos de Tortugas Terrestres     

RECENT COAL AND URANIUM INVESTMENT AGREEMENTS IN THE THIRD WORLD

The improvements made by developing countries in the 1970s in petroleum and mineral agreements with transnational corporations have been well documented, and substantial evidence exists to show that some real gains, in terms of host country control over operations, distribution of economic benefits, better employment and training requirements, etc., have in fact been made. In the case of the energy-related minerals, uranium and coal, however, relatively few contracts between Third World governments and transnational corporations have become public, and it is thus difficult to document whether the same gains made in the case of petroleum or non-fuel minerals have been achieved in relation to these energy resources. This article reviews a number of such recent coal and uranium agreements in developing countries. In overall terms, these agreements do not go as far in providing for the interests of host countries as do those negotiated for petroleum or hard minerals. The reasons for this apparent weakness in developing countries' bargaining power in the case of uranium and coal include the specific nature of the markets for these minerals, the structure of transnational corporations in the industry, and the very secrecy which has kept most of these contracts from public view. In the light of the relatively weak markets expected for export sales of coal and uranium through the remainder of the 1980s, it appears unlikey that developing countries can make significant advances in their negotiations to the extent of achieving terms which are more favourable than those contained in the best of the agreements reviewed in this article. It should, however, be possible for host governments to use the more favourable of the agreements reviewed here as standards for future negotiations. Une solide documentation existe sur les améliorations apportées par les pays en développement dans les années '70 dans le domaine des accords pétroliers et miniers avec les sociétés multinationales et il est maintenant bien etabli que des gains réels ont été acquis en ce qui concerne le contrôle des opérations par le pays hôte, la répartition des bénéfices, une meilleure utilisation de la main-d'oeuvre et les obligations de formation professionnelle. Cependant, dans le cas des minerais énergétiques uranium et charbon, relativement très peu de contrats intervenus entre les gouvernements du Tiers Monde et les sociétés multinationales sont tombés dans le domaine public de sorte qu'il est difficile d'établir si des gains semblables à ceux réalisés dans le cadre du pétrole et des minerais métalliques ont été obtenus. Cet article passe en revue certains des accords intervenus récemment dans les domaines du charbon et de l'uranium dans les pays en développement. En termes généraux, ces accords ne vont pas aussi loin dans la protection des intérêts des pays hôtes que ceux qui ont été négociés pour le pétrole et les minerais. La marge de manoeuvre des pays en développement dans le cadre des négociations d'accords portant sur le charbon et l'uranium est limitée en apparence du fait de la nature particulière des marchés de ces minerais, de la place qu'occupent les sociétés multinationales dans l'industrie minière et du caractère confidentiel qui entoure les transactions et les isole de la vue du grand public. Etant donné les tendances baissières des marchés du charbon et de l'uranium à l'exportation pour le reste de cette décennie, il semble peu probable que les pays en développement puissent réaliser des progrès sensibles dans leurs négociations pour atteindre des conditions plus favorables que celles qui figurent dans les meilleurs accords examinés dans cet article. Cependant, les pays hôtes devraient se prévaloir des accords qui leur sont les plus favorables parmi ceux qui sont passés en revue pour les utiliser comme base de leurs futures négociations et tout au moins pour éviter de signer des accords léonins. Los progresos alcanzados en la década del setenta por los países en desar-rollo en los acuerdos con las compañias transnacionales sobre el desarrollo del petróleo y de los minerales ha sido bien documentado y existe evidencia sustantiva de que ha habido ganancias reales en aspectos tales como control del país sobre las operaciones, distribución de beneficios económicos, mejores condiciones para el empleo y el entrenamiento, etc. Sin embargo, en el caso de minerales energéticos, tales como el uranio y el carbón, pocos contratos han sido hechos públicos y es difícil documentar si se tuvieron similares ganancias como en el caso de minerales no energéticos y petróleo. Este artículo pasa revista a un número de dichos contratos recientes sobre carbón y uranio. En términos generales estos contratos no son tan favorables a los países en desarrollo en comparación con los contratos para petróleo y minerales no energéticos. Las razones para esta aparente debilidad del poder de negociación en el caso del carbón y del uranio se debe, entre otras, a la naturaleza específica del mercado para estos minerales, la estruc-tura de las compañías transnacionales dentro de la indústria y el carácter secreto que ha tenido la mayoría de estos contratos con respecto al público en general. A la luz de la relativa debilidad del mercado para las exportaciones de carbón y uranio que se cree que imperará durante el resto de la década del ochenta, parece poco probable que los países en desarrollo puedan hacer avances significativos en sus negociaciones con el objeto de alcanzar términos que sean más favorables que los que se alcanzaron en el mejor de los contratos revisados en el presente artículo. Debería ser posible, sin embargo, que los gobiernos puedan usar como patrón para futuras negociaciones el contrato mas favorable revisado en este artículo y evitar la firma de acuerdos totalmente desfavorables al pais.     

Potato Diversity in the Andean Center of Crop Domestication

The diversity and population structure of potato landraces ( Solanum spp.) within their center of domestication was studied using isozyme surveys of four polymorphic loci. The objective in assessing the distribution of genetic diversity was to assist in planning conservation strategies of crop genetic resources that are threatened by genetic erosion. In situ conservation methods depend on this type of analysts. Research was conducted in the region of Cusco, Peru. Eight fields spread among two microregions were randomly sampled, and 610 tubers were studied from this sample. In addition, 503 tubers were collected from markets in seven different meso-regions (provinces) surrounding the regional center of Cusco. Thirty genotypes were identified in the field sample and 82 in the regional sample. The frequency and distribution of genotypes and alleles are described. A high degree of genotype endemism was found at both the field and regional levels. Genotypes were unevenly distributed, and most of the genotypic diversity was between rather than within populations. At the allele level, however, we found that a very high percentage of the diversity was within rather than between populations. The genotype is the key unit for maintaining the population of potato landraces. Our findings suggest that collections need to be both geographically extensive and intensive. Because farmers are able to maintain most alleles on relatively small portions of their land, in situ conservation is a viable strategy.