Minton G.,WWF Gabon |
Zulkifli Poh A.N.,University Malaysia Sarawak |
Peter C.,University Malaysia Sarawak |
Porter L.,University of St. Andrews |
Kreb D.,Yayasan Konservasi RASI
Advances in marine biology | Year: 2016
Indo-Pacific humpback dolphins (Sousa chinensis) are documented from various locations along Borneo's coast, including three sites in Sarawak, Malaysia, three sites in Sabah, Malaysia, three locations in Kalimantan, Indonesia and the limited coastal waters of the Sultanate of Brunei. Observations in all these areas indicate a similar external morphology, which seems to fall somewhere between that documented for Chinese populations known as S. chinensis, and that of Sousa sahulensis in Australia and Papua New Guinea. Sightings occur in shallow nearshore waters, often near estuaries and river mouths, and associations with Irrawaddy dolphins (Orcaella brevirostris) are frequently documented. Population estimates exist for only two locations and sightings information throughout Borneo indicates that frequency of occurrence is rare and group size is usually small. Threats from fisheries by-catch and coastal development are present in many locations and there are concerns over the ability of these small and fragmented populations to survive. The conservation and taxonomic status of humpback dolphins in Borneo remain unclear, and there are intriguing questions as to where these populations fit in our evolving understanding of the taxonomy of the genus. © 2016 Elsevier Ltd. All rights reserved.
Meunier Q.,Nature Plus asbl |
Boldrini S.,Nature Plus asbl |
Moumbogou C.,WWF Gabon |
Morin A.,Nature Plus asbl |
And 2 more authors.
Bois et Forets des Tropiques | Year: 2014
Slash-and-burn cultivation is still widespread among the vast majority of ethnolinguistic groups in Gabon, and likely to remain so in the future. It generally occurs within a five-kilometre radius around each settlement. In Gabon, this is the zone earmarked since late 2013 for the country's first community forests. The principles of sustainability underlying the idea of community forestry imply that forest cover should be preserved. However, this can conflict with slash-and-burn farming, which removes a certain amount of timber production potential from the area concerned every year. The simplified management plans for community forestry provide for cropping sequences in order to avoid competition between the two activities on the same land. This provision also acknowledges the important social and economic role of farming in rural areas. Agro-forestry is one of the keys to maintaining family farming together with community forestry. Preserving standing trees of social, economic or environmental value lessens the arduous task of felling while quantitatively reducing the impact of slashing and burning, which is no longer systematic. Introducing useful, rare or protected species or valuable timber trees also increases the economic and heritage value of agricultural lands while meeting the conservation and sustainability requirements of the simplified management plans for community forests. Traditional family farming can thus be maintained and made secure within a legally recognised portion of the forest, together with optimised cultivation techniques.
Fossette S.,University of Swansea |
Fossette S.,National Oceanic and Atmospheric Administration |
Witt M.J.,University of Exeter |
Nalovic M.A.,Virginia Institute of Marine Science |
And 24 more authors.
Proceedings of the Royal Society B: Biological Sciences | Year: 2014
Large oceanic migrants play important roles in ecosystems, yet many species are of conservation concern as a result of anthropogenic threats, of which incidental capture by fisheries is frequently identified. The last large populations of the leatherback turtle, Dermochelys coriacea, occur in the Atlantic Ocean, but interactions with industrial fisheries could jeopardize recent positive population trends, making bycatch mitigation a priority. Here, we perform the first pan Atlantic analysis of spatio-temporal distribution of the leatherback turtle and ascertain overlap with longline fishing effort. Data suggest that the Atlantic probably consists of two regional management units: northern and southern (the latter including turtles breeding in South Africa). Although turtles and fisheriesshow highly diverse distributions, we highlight nine areas of high susceptibility to potential bycatch (four in the northern Atlantic and five in the southern/equatorial Atlantic) that are worthy of further targeted investigation and mitigation. These are reinforced by reports of leatherback bycatch at eight of these sites. International collaborative efforts are needed, especially from nations hosting regions where susceptibility to bycatch is likely to be high within their exclusive economic zone (northern Atlantic: Cape Verde, Gambia, Guinea Bissau, Mauritania, Senegal, Spain, USA and Western Sahara; southern Atlantic: Angola, Brazil, Namibia and UK) and from nations fishing in these high-susceptibility areas, including those located in international waters. © 2014 The Authors.
Fossette S.,University of Strasbourg |
Fossette S.,French National Center for Scientific Research |
Fossette S.,University of Swansea |
Girard C.,University of Strasbourg |
And 13 more authors.
PLoS ONE | Year: 2010
Background: Sea turtles are long-distance migrants with considerable behavioural plasticity in terms of migratory patterns, habitat use and foraging sites within and among populations. However, for the most widely migrating turtle, the leatherback turtle Dermochelys coriacea, studies combining data from individuals of different populations are uncommon. Such studies are however critical to better understand intra- and inter-population variability and take it into account in the implementation of conservation strategies of this critically endangered species. Here, we investigated the movements and diving behaviour of 16 Atlantic leatherback turtles from three different nesting sites and one foraging site during their post-breeding migration to assess the potential determinants of intra- and inter-population variability in migratory patterns. Methodology/Principal Findings: Using satellite-derived behavioural and oceanographic data, we show that turtles used Temporary Residence Areas (TRAs) distributed all around the Atlantic Ocean: 9 in the neritic domain and 13 in the oceanic domain. These TRAs did not share a common oceanographic determinant but on the contrary were associated with mesoscale surface oceanographic features of different types (i.e., altimetric features and/or surface chlorophyll a concentration). Conversely, turtles exhibited relatively similar horizontal and vertical behaviours when in TRAs (i.e., slow swimming velocity/sinuous path/shallow dives) suggesting foraging activity in these productive regions. Migratory paths and TRAs distribution showed interesting similarities with the trajectories of passive satellite-tracked drifters, suggesting that the general dispersion pattern of adults from the nesting sites may reflect the extent of passive dispersion initially experienced by hatchlings. Conclusions/Significance: Intra- and inter-population behavioural variability may therefore be linked with initial hatchling drift scenarios and be highly influenced by environmental conditions. This high degree of behavioural plasticity in Atlantic leatherback turtles makes species-targeted conservation strategies challenging and stresses the need for a larger dataset (>100 individuals) for providing general recommendations in terms of conservation. © 2010 Fossette et al.
Pikesley S.K.,University of Exeter |
Agamboue P.D.,Wildlife Conservation Society |
Bonguno E.A.,Agence Nationale des Parcs Nationaux |
Boussamba F.,British Petroleum |
And 15 more authors.
Biological Conservation | Year: 2013
The African country of Gabon has seen decadal increases in commercial logging. An unforeseen consequence of this has been that many coastal areas, including several National Parks and Reserves, have suffered severe pollution from beached timber. This has the potential to adversely affect nesting sea turtles, particularly the leatherback turtle (Dermochelys coriacea) for which Gabon constitutes the world's largest rookery. In this study, we analyse aerial survey data (2003, 2007 and 2011) to determine the temporal persistence and spatial extent of beached timber, and by integrating spatial data on nesting, ascertain regions where beached timber poses the greatest threat to nesting leatherback turtles. There was no marked difference in the number of beached logs recorded across the study area during the period, with 15,160, 13,528 and 17,262 logs recorded in the three years, respectively. There was, however, a significant difference in abundance of beached logs among geographical areas. Analysis highlighted two coastal areas where nesting leatherback turtles were likely to be at greatest risk from beached timber. At one such site, Kingere, within Pongara National Park, where both logs and turtle densities are high, monitoring in 2006/2007 and 2007/2008 suggested that between 1.6% and 4.4% of leatherback turtles could be entrapped at this site. Given the dynamic nature of Gabon's coastal environment, and the potential limitations of aerial surveys, densities of beached timber could be greater than this analysis reveals. We also propose, that despite recent export restrictions of whole logs, their environmental persistence potentially represents a long-term problem. © 2012.