Feeding preference and seed dispersion by Roussetus madagascariensis Grandidier 1928 in North-western Madagascar

Experiments in a flight cage and observations in the field were carried out in North-western Madagascar to study the feeding preference of Rousettus madagascariensis (Family Pteropodidae) between an introduced fruit, jujube (Ziziphus jujuba, Family Rhamnaceae) and an endemic fig (Ficus sakalavarum, Family Moraceae) during the dry season, in May and June 2009. We also investigated quantitative aspects of seed dispersion by R. madagascariensis. Juvenile bats (13) fed intensively on F. sakalavarum, while adults (20) ate both fruit species but with a pronounced preference for unripe Z. jujube fruits. This preference for unripe (immature) fruit, the seeds of which are too large to swallow, suggested that R. madagascariensis does not affect seed dispersal in Z. jujuba. Almost half of the ingested seeds of F. sakalavarum were found in faeces of R. madagascariensis voided during the night in the flight cage, and the remainder was found in regurgitated ‘ejecta’ pellets. Rousettus madagascariensis is thought to be an effective seed disperser of F. sakalavarum, particularly for isolated trees or those in forest fragments where other frugivores are rareDes expériences dans une volière ou cage d'expérimentation et des observations in natura à proximité des arbres ont été réalisées dans la région nord-ouest de Madagascar pour étudier le choix de Rousettus madagascariensis (famille Pteropodidae) entre une espèce de fruit introduite le Jujubier (Ziziphus jujuba, famille Rhamnaceae) et une espèce de figuier endémique (Ficus sakalavarum, famille Moraceae) au cours de la saison sèche. L'aspect quantitatif de la dissémination des graines de cette dernière a également été étudié. Cette étude a été menée en mai et juin 2009. Rousettus madagascariensis utilise les deux espèces, mais la préférence entre les deux fruits varie en fonction de l'âge de l'animal. Les jeunes chauves-souris ont une préférence pour Ficus sakalavarum tandis que les adultes mangent aussi les jujubes qui ne sont généralement pas très mûrs et même si leur graine est trop volumineuse pour être avalée. Nous suggérons que cet animal n'assure pas la dissémination des graines de Z. jujuba. La dissémination des graines par cette espèce pourrait être moins favorable par rapport aux autres animaux qui avalent les graines. Presque la moitié des graines de F sakalavarum a été trouvée dans les fèces de R. madagascariensis laissés pendant la nuit dans la volière, le reste a été recraché sous forme de pelotes de régurgitation. Rousettus madagascariensis participe activement à la dissémination des graines de F. sakalavarum plus particulièrement celles de pieds isolés ou se trouvant dans des fragments d'habitats restreints où les autres animaux disséminateurs sont rares ou absents

Drainage of a deep magma reservoir near Mayotte inferred from seismicity and deformation

The dynamics of magma deep in the Earth’s crust are difficult to capture by geophysical monitoring. Since May 2018, a seismically quiet area offshore of Mayotte in the western Indian Ocean has been affected by complex seismic activity, including long-duration, very-long-period signals detected globally. Global Navigation Satellite System stations on Mayotte have also recorded a large surface deflation offshore. Here we analyse regional and global seismic and deformation data to provide a one-year-long detailed picture of a deep, rare magmatic process. We identify about 7,000 volcano-tectonic earthquakes and 407 very-long-period seismic signals. Early earthquakes migrated upward in response to a magmatic dyke propagating from Moho depth to the surface, whereas later events marked the progressive failure of the roof of a magma reservoir, triggering its resonance. An analysis of the very-long-period seismicity and deformation suggests that at least 1.3 km3 of magma drained from a reservoir of 10 to 15 km diameter at 25 to 35 km depth. We demonstrate that such deep offshore magmatic activity can be captured without any on-site monitoring

Mitochondrial DNA diversity and population structure of humpback whales from their wintering areas in the Indian and South Atlantic Oceans (Wintering Regions A,B, C and X). Scientific Committee document SC/56/SH3, International Whaling Commission, July 2004, Sorrento, Italy

Humpback whales in the Southern Hemisphere are separated by the International Whaling Commission (IWC) into seven wintering Regions (A-G) based on tropical distribution. To better evaluate the significance of these stock subdivisions, an analysis of mtDNA was conducted for the eastern and western South Atlantic (Regions A and B), the southwestern Indian Ocean (Region C) and the northern Indian Ocean (Region X). A total of 1,416 individual whales representing eleven sampling sites within the four wintering Regions were sequenced for a portion of the mtDNA control region. A hierarchical analysis of molecular variance (AMOVA) using FST and FST supported the division of wintering Regions based on IWC designated boundaries of A, B, C, and X. Pairwise comparisons further confirmed the A, B and C divisions, although varying degrees of heterogeneity (particularly molecular distances) were detected for proposed sub-divisions within Regions B and C. Overall, this large-scale mtDNA analysis for humpback whales in the Indian and South Atlantic Oceans supports wintering Region designations by the IWC. However, additional analyses and consideration of biological parameters such as gene flow are needed so that ‘within-region’ genetic analyses can help evaluate population structure and recovery in a management context

Twenty-first-century trade governance: findings from the Commonwealth countries

© 2019 Western Economic Association International This paper focuses on twenty-first-century-trade governance patterns within the Commonwealth (CW) countries. It uses an augmented gravity model to examine the role of governance in influencing trade and investment flows, and whether enhanced trade governance within the CW countries could potentially foster trade gains, on a both intra- and extra-CW basis. Results show a 10% reduction in the costs incurred for a good to exit a country can increase intra-CW exports by 5%. Second, contract enforcement is more efficient among CW members, and requires 20% less time compared to the world average. Third, every 1 percentage point improvement in government effectiveness triggers an increase in exports from CW, at 3.4%, compared to the rest of the world, at 2.4%. Finally, trade between CW members is three times higher when they belong to an existing regional trade agreement (F10, 011, F13)

The first Forecasters Handbook for West Africa

Bridging the gap between rapidly moving scientific research and specific forecasting tools, Meteorology of Tropical West Africa: The Forecasters' Handbook’, gives unprecedented access to the latest science and combines this with pragmatic approaches to forecasting. It is set to change the way forecasters, researchers and students learn about tropical meteorology and will serve to drive demand for new forecasting tools. The Handbook builds upon the legacy of the AMMA project, making the latest science applicable to forecasting in the region. By bringing together, at the outset, researchers and forecasters from across the region, and linking to applications, user communities and decision-makers, the Forecasters’ Handbook provides a template for finding much needed solutions to critical issues such as building resilience to climate change in West Africa

Population Structure of Humpback Whales from Their Breeding Grounds in the South Atlantic and Indian Oceans

Although humpback whales are among the best-studied of the large whales, population boundaries in the Southern Hemisphere (SH) have remained largely untested. We assess population structure of SH humpback whales using 1,527 samples collected from whales at fourteen sampling sites within the Southwestern and Southeastern Atlantic, the Southwestern Indian Ocean, and Northern Indian Ocean (Breeding Stocks A, B, C and X, respectively). Evaluation of mtDNA population structure and migration rates was carried out under different statistical frameworks. Using all genetic evidence, the results suggest significant degrees of population structure between all ocean basins, with the Southwestern and Northern Indian Ocean most differentiated from each other. Effective migration rates were highest between the Southeastern Atlantic and the Southwestern Indian Ocean, followed by rates within the Southeastern Atlantic, and the lowest between the Southwestern and Northern Indian Ocean. At finer scales, very low gene flow was detected between the two neighbouring sub-regions in the Southeastern Atlantic, compared to high gene flow for whales within the Southwestern Indian Ocean. Our genetic results support the current management designations proposed by the International Whaling Commission of Breeding Stocks A, B, C, and X as four strongly structured populations. The population structure patterns found in this study are likely to have been influenced by a combination of long-term maternally directed fidelity of migratory destinations, along with other ecological and oceanographic features in the region